US20260022867A1

US20260022867A1 - Vapor refrigeration system and method for using same

Info

Publication number: US20260022867A1
Application number: US19/265,945
Authority: US
Inventors: Jeffrey Jones; Heather Jones
Original assignee: Elkhorn Products Inc
Current assignee: Elkhorn Products Inc
Priority date: 2024-07-17
Filing date: 2025-07-10
Publication date: 2026-01-22
Also published as: WO2026019657A1

Abstract

A refrigeration system may comprise a fluid tank for storing a supply of water. A water pump may be fluidly coupled to the fluid tank, configured to circulate water from the fluid tank. An eductor may be in fluid communication with the water pump, the eductor may be operative to create a vacuum by utilizing a flow of water from the water pump. A vacuum chamber may be fluidly connected to the eductor, wherein the vacuum chamber may be structured to facilitate the evaporation of water under vacuum conditions to absorb heat from a refrigerant. A heat exchanger may be in thermal communication with the vacuum chamber, the heat exchanger may be configured to transfer heat from the refrigerant to the evaporated water. A condenser may be fluidly connected to the vacuum chamber, configured to condense the evaporated water and to discharge the heat absorbed from the refrigerant.

Description

RELATED APPLICATION

Under provisions of 35 U.S.C. § 119(e), the Applicant claims benefit of U.S. Provisional Application No. 63/672,464 filed on Jul. 17, 2024, and having inventors in common, which is incorporated herein by reference in its entirety.
It is intended that the referenced application may be applicable to the concepts and embodiments disclosed herein, even if such concepts and embodiments are disclosed in the referenced application with different limitations and configurations and described using different examples and terminology.

FIELD OF DISCLOSURE

The present disclosure generally relates to refrigeration systems and methods. More particularly, the present disclosure relates to fluid (e.g., water) vacuum refrigeration systems utilizing phase change principles to facilitate heat transfer through the latent heat of vaporization of the fluid under vacuum conditions.

BACKGROUND

In some situations, refrigeration and cooling systems are required to maintain controlled temperatures for a variety of applications including food preservation, climate control, and industrial processes. For example, commercial refrigeration systems are essential in food storage facilities, while industrial cooling systems are critical for manufacturing processes, data centers, and chemical production. Thus, the conventional strategy is to employ vapor compression refrigeration systems that use synthetic as well as natural refrigerants and mechanical compressors to achieve the desired cooling effect. This often causes problems because the conventional strategy does not achieve optimal energy efficiency or environmental sustainability. For example, traditional vapor compression systems typically operate at high pressures, often exceeding 400 PSI, which necessitates robust components and complex oil management systems.
Conventional refrigeration systems predominantly rely on mechanical compression to increase the pressure and temperature of refrigerants. These systems utilize synthetic refrigerants that may have significant global warming potential or contribute to ozone depletion. The compression process in these systems requires substantial electrical power, contributing to high operational costs and environmental impact. During operation, compressors generate additional heat, increasing the total cooling load by up to 25%.
Current industrial refrigeration solutions typically achieve Coefficients of Performance (COPs) between 2.5-4.0, far below theoretical efficiency limits. The high-pressure operation of these systems leads to increased maintenance requirements and higher risk of system failures. Additionally, the complexity of traditional systems results in significant installation costs and ongoing maintenance expenses.
For cascade refrigeration systems, which use multiple refrigeration cycles operating at different temperature levels, traditional approaches require multiple mechanical compression stages. Each stage typically uses its own refrigerant and compressor, adding to system complexity and energy consumption. The condenser of one cycle rejects heat to the evaporator of another cycle, allowing for efficient cooling at very low temperatures, but the overall efficiency is limited by the compressor-based design.
The management of synthetic refrigerants poses additional challenges, as these substances must be carefully contained and handled to prevent environmental harm. International agreements such as the Montreal Protocol and Kigali Amendment have established phase-out schedules for many synthetic refrigerants, creating regulatory pressure on the refrigeration industry to develop more environmentally friendly alternatives.
In applications such as data centers, which represent a significant portion of global energy consumption, the limitations of conventional cooling solutions are particularly problematic. These facilities face challenges with heat density and often have geographical or environmental restrictions that make traditional cooling approaches less effective or efficient.
In specialized cooling applications such as medical and pharmaceutical storage, traditional refrigeration systems often struggle to maintain the precise temperature control required for sensitive materials. These environments demand temperature stability within ±0.5° C., which conventional systems frequently fail to deliver due to compressor cycling and pressure fluctuations. The resulting temperature variations can compromise vaccine efficacy or biological sample integrity, leading to significant product loss.
Data center cooling presents another critical challenge, with high-density server environments generating heat loads exceeding 30 kW per rack. Traditional air-cooling methods become inefficient at these densities, requiring excessive airflow that creates hot spots and reduces overall cooling effectiveness. The energy consumption for data center cooling alone can represent 40% of a facility's total power usage, creating substantial operational expenses and environmental impact.
In food processing and cold storage facilities, conventional refrigeration systems face difficulties maintaining optimal humidity levels alongside temperature control. These systems typically reduce air humidity during the cooling process, causing product dehydration and weight loss that can reach 3-5% in fresh produce. This moisture loss not only affects product quality but also represents direct financial losses for operators.
Industrial process cooling applications encounter limitations with traditional systems when rapid temperature changes are required. Manufacturing processes that demand quick cooling cycles between production stages often experience bottlenecks as conventional refrigeration cannot respond quickly enough to thermal load variations. This leads to production delays and inconsistent product quality in industries such as plastics manufacturing and metal processing.
Transportation refrigeration faces unique challenges related to size constraints and power availability. Mobile cooling systems must function efficiently while operating from limited power sources and within restricted space envelopes. Current solutions often compromise on cooling capacity or energy efficiency to meet these constraints, resulting in inadequate temperature maintenance during transit and increased fuel consumption.
In extreme climate regions, conventional refrigeration systems experience significant efficiency losses when ambient temperatures exceed design parameters. High- temperature environments can reduce system capacity by up to 30% while increasing energy consumption, creating reliability issues precisely when cooling is most critical. These systems frequently experience premature component failure due to the additional stress of operating in high-temperature conditions.
Marine refrigeration systems face challenges related to corrosion resistance, space limitations, and the need to operate reliably in constantly changing conditions. Conventional systems typically require frequent maintenance and component replacement in these harsh environments, leading to higher operational costs and potential cooling failures that can compromise cargo or onboard provisions.
For low-temperature scientific applications, such as laboratory freezers maintaining temperatures below −80° C., cascade refrigeration systems using multiple refrigeration stages and different refrigerants are typically employed. These systems are complex, maintenance-intensive, and consume substantial energy. The multiple compressors required generate significant heat that must itself be removed, further reducing overall system efficiency.
In specialized applications requiring precise temperature control, conventional refrigeration systems face significant limitations. For example, in pharmaceutical cold storage, traditional vapor compression systems often struggle to maintain the narrow temperature range of ±0.5° C. needed for sensitive biologicals and vaccines. These systems frequently experience temperature fluctuations due to compressor cycling that can compromise product integrity, resulting in substantial financial losses when high-value pharmaceuticals are rendered ineffective.
Absorption refrigeration systems represent one alternative approach, using heat energy rather than mechanical compression to drive the refrigeration cycle. These systems typically employ ammonia-water or lithium bromide-water working pairs. While they can operate with low-grade heat sources such as solar energy or waste heat, they generally achieve COPs of only 0.7-1.2, significantly lower than conventional vapor compression systems. Additionally, their bulky design and limited capacity for rapid temperature adjustment make them unsuitable for many commercial and industrial applications.
Magnetic refrigeration systems, based on the magnetocaloric effect, have emerged as another potential solution. These systems use magnetic materials that heat up when exposed to a magnetic field and cool when the field is removed. While promising for their potential efficiency and absence of harmful refrigerants, current magnetic refrigeration prototypes achieve limited temperature differentials and cooling capacities. The specialized materials required also make these systems prohibitively expensive for widespread commercial adoption.
Thermoelectric cooling, utilizing the Peltier effect, offers a solid-state cooling solution without moving parts or refrigerants. However, these systems typically achieve COPs of only 0.4-0.7, making them highly inefficient for applications requiring significant cooling capacity. Their practical use is generally limited to small-scale applications like portable coolers or electronic component cooling where efficiency is less critical than size or reliability.
Ejector refrigeration systems use high-pressure motive fluid to entrain and compress a secondary fluid, potentially eliminating the mechanical compressor. While these systems can operate with low-grade heat sources, they typically achieve COPs of only 0.2-0.5 when used as standalone refrigeration systems. Their efficiency is highly sensitive to operating conditions, making them unreliable in environments with fluctuating temperatures or cooling demands.
Transcritical CO2 refrigeration systems have gained attention as environmentally friendly alternatives to systems using synthetic refrigerants. However, these systems operate at extremely high pressures, often exceeding 1,500 PSI, requiring specialized components and rigorous safety measures. Their efficiency drops significantly in high ambient temperatures, necessitating complex system designs with parallel compression or ejectors to maintain performance in warm climates.
For data center cooling applications, direct liquid cooling technologies have been developed to address the limitations of traditional air cooling. These systems circulate dielectric fluids directly through server components to remove heat more efficiently. However, they require significant modifications to standard IT equipment and present challenges related to fluid leakage and maintenance. The specialized fluids used also raise concerns about long-term environmental impact and disposal requirements.
In the food processing industry, cryogenic freezing systems using liquid nitrogen or carbon dioxide provide rapid freezing capabilities that conventional refrigeration cannot match. However, these systems require continuous supply of cryogenic fluids, creating operational dependencies and significant ongoing costs. The extremely low temperatures involved also present safety hazards and require specialized handling procedures and equipment.
District cooling systems, which centralize cooling production and distribute chilled water to multiple buildings, offer efficiency advantages through economies of scale. However, these systems require extensive underground infrastructure and face significant heat losses during distribution, particularly in areas with high ground temperatures. The centralized nature also creates single points of failure that can affect cooling for entire districts.
For ultra-low temperature applications such as biological sample storage, cascade refrigeration systems using multiple refrigeration stages are commonly employed. These systems typically use two or more separate refrigeration cycles with different refrigerants to achieve temperatures below −80° C. The complexity of these systems results in high initial costs, substantial maintenance requirements, and significant energy consumption, with COPs typically below 1.0 at ultra-low temperatures.
These limitations in current refrigeration technologies highlight the need for innovative approaches that can deliver higher energy efficiency, reduced environmental impact, and improved performance across diverse applications ranging from medical storage to industrial process cooling and data center thermal management.
Despite significant technological advances in refrigeration and cooling systems, there remains a pressing need for more efficient, environmentally sustainable cooling solutions across diverse applications. Current systems face substantial limitations in meeting the increasingly demanding requirements of modern cooling applications while simultaneously addressing growing environmental concerns. The precision temperature control required in pharmaceutical storage, the extreme heat loads generated in high-density data centers, the humidity management challenges in food processing, the rapid cooling needs in manufacturing, the space and power constraints in transportation refrigeration, the efficiency losses in extreme climates, the specialized requirements in agricultural cooling, the harsh operating conditions in marine environments, and the complexity of ultra-low temperature scientific applications all highlight critical gaps in conventional cooling technologies. These challenges are further compounded by the regulatory pressure to phase out synthetic refrigerants with high global warming potential, creating an urgent need for innovative approaches that can deliver higher energy efficiency, reduced environmental impact, and improved performance across the full spectrum of refrigeration applications.

BRIEF OVERVIEW

This brief overview is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This brief overview is not intended to identify key features or essential features of the claimed subject matter. Nor is this brief overview intended to be used to limit the claimed subject matter's scope.
A refrigeration system may comprise a fluid tank for storing a supply of fluid. A fluid pump may be fluidly coupled to the fluid tank, configured to circulate fluid from the fluid tank. An eductor may be in fluid communication with the fluid pump, the eductor being operative to create a vacuum by utilizing a flow of fluid from the fluid pump. A vacuum chamber may be fluidly connected to the eductor, wherein the vacuum chamber may be structured to facilitate the evaporation of fluid under vacuum conditions to absorb heat from a refrigerant. A heat exchanger may be in thermal communication with the vacuum chamber, the heat exchanger being configured to transfer heat from the refrigerant to the evaporated fluid. A condenser may be fluidly connected to the vacuum chamber, the condenser being configured to condense the evaporated fluid and to discharge the heat absorbed from the refrigerant.
The fluid pump may be characterized by a variable flow rate to control the volume of fluid supplied to the eductor based on operational demands of the system. The eductor may comprise a nozzle designed to maximize reduction in pressure to achieve a desired boiling point of the fluid for efficient heat absorption. The vacuum chamber may include a float mechanism to maintain a predetermined level of the fluid within the chamber, ensuring consistent evaporation.
The heat exchanger may be specifically configured for use with a CO2 refrigerant in a subcritical state, facilitated by a cooling effect of the evaporated fluid. The condenser may be equipped with a heat rejection unit capable of transferring heat to an external environment or a secondary heat utilization system. The system may further comprise a control unit programmed to monitor and adjust pressure within the vacuum chamber, flow rate of the water pump, and temperature of the condenser.
The system may further comprise a vapor separation tank positioned between the eductor and the fluid storage tank, the vapor separation tank being configured to separate entrained liquid from vapor. The system may be configured to operate as a high stage in a cascade refrigeration system with a secondary refrigerant circuit. The system may further comprise a liquid ring vacuum pump as an alternative mechanism for maintaining vacuum within the vacuum chamber.
In some embodiments, the system may include a plurality of sensors for real-time monitoring of temperature, pressure, and water flow rates within the system. A bypass valve system may be included for selectively isolating components of the system during maintenance operations. The system may be configurable to operate in multiple modes to accommodate varying environmental conditions and cooling load requirements. The system may further comprise a cascade configuration wherein the system serves as a high stage for a low-temperature refrigeration system.
A method for refrigeration may comprise circulating water from a water tank through a water pump. The method may include directing the water through an eductor to create a vacuum. The method may include transferring the water under vacuum to a vacuum chamber where the water may be evaporated to absorb heat from a medium to be cooled. The method may include conveying the evaporated water to a condenser where the water may be condensed. The method may include returning the condensed water to the water tank.
A refrigeration system may comprise a water tank for storing a supply of water. A water pump may be fluidly coupled to the water tank, configured to circulate water from the water tank. An eductor may be in fluid communication with the water pump, the eductor being operative to create a vacuum by utilizing a flow of water from the water pump. A vacuum chamber may be fluidly connected to the eductor, wherein the vacuum chamber may be structured to facilitate the evaporation of water under vacuum conditions to absorb heat from a refrigerant. A heat exchanger may be in thermal communication with the vacuum chamber, the heat exchanger being configured to transfer heat from the refrigerant to the evaporated water. A condenser may be fluidly connected to the vacuum chamber, the condenser being configured to condense the evaporated water and to discharge the heat absorbed from the refrigerant. A cascade configuration may be included wherein the system may serve as a high stage for a low-temperature refrigeration system.
A refrigeration system may comprise a water tank configured to store water. A first water pump may be fluidly coupled to the water tank. A first eductor may be fluidly connected to the first water pump, the first eductor configured to create a vacuum using water from the first water pump. An evaporator may be fluidly connected to the first eductor, the evaporator configured to facilitate water evaporation under vacuum conditions. A second water pump may be fluidly coupled to the water tank. A second eductor may be fluidly connected to the second water pump. A condenser may be fluidly connected to the second eductor and to the water tank, the condenser configured to receive water vapor from the water tank and condense the water vapor.
Both the foregoing brief overview and the following detailed description provide examples and are explanatory only. Accordingly, the foregoing brief overview and the following detailed description should not be considered to be restrictive. Further, features or variations may be provided in addition to those set forth herein. For example, embodiments may be directed to various feature combinations and sub-combinations described in the detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate various embodiments of the present disclosure. The drawings contain representations of various trademarks and copyrights owned by the Applicant. In addition, the drawings may contain other marks owned by third parties and are being used for illustrative purposes only. All rights to various trademarks and copyrights represented herein, except those belonging to their respective owners, are vested in and the property of the Applicant. The Applicant retains and reserves all rights in its trademarks and copyrights included herein, and grants permission to reproduce the material only in connection with reproduction of the granted patent and for no other purpose.

Furthermore, the drawings may contain text or captions that may explain certain embodiments of the present disclosure. This text is included for illustrative, non-limiting, explanatory purposes of certain embodiments detailed in the present disclosure. In the drawings:

FIG. 1 shows depictions of a refrigeration system in accordance with an embodiment of the present disclosure;

FIG. 2 shows depictions of a refrigeration system in accordance with another embodiment of the present disclosure;

FIG. 3 is a depiction of a refrigeration system in accordance with another embodiment of the present disclosure; and

FIG. 4 is a depiction of a refrigeration system in accordance with another embodiment of the present disclosure.

DETAILED DESCRIPTION

As a preliminary matter, it will readily be understood by one having ordinary skill in the relevant art that the present disclosure has broad utility and application. As should be understood, any embodiment may incorporate only one or a plurality of the above-disclosed aspects of the disclosure and may further incorporate only one or a plurality of the above-disclosed features. Furthermore, any embodiment discussed and identified as being “preferred” is considered to be part of a best mode contemplated for carrying out the embodiments of the present disclosure. Other embodiments also may be discussed for additional illustrative purposes in providing a full and enabling disclosure. Moreover, many embodiments, such as adaptations, variations, modifications, and equivalent arrangements, will be implicitly disclosed by the embodiments described herein and fall within the scope of the present disclosure.
Accordingly, while embodiments are described herein in detail in relation to one or more embodiments, it is to be understood that this disclosure is illustrative and exemplary of the present disclosure and are made merely to provide a full and enabling disclosure. The detailed disclosure herein of one or more embodiments is not intended, nor is to be construed, to limit the scope of patent protection afforded in any claim of a patent issuing here from, which scope is to be defined by the claims and the equivalents thereof. It is not intended that the scope of patent protection be defined by reading into any claim a limitation found herein that does not explicitly appear in the claim itself.
Thus, for example, any sequence(s) and/or temporal order of steps of various processes or methods that are described herein are illustrative and not restrictive. Accordingly, it should be understood that, although steps of various processes or methods may be shown and described as being in a sequence or temporal order, the steps of any such processes or methods are not limited to being carried out in any particular sequence or order, absent an indication otherwise. Indeed, the steps in such processes or methods generally may be carried out in various different sequences and orders while still falling within the scope of the present invention. Accordingly, it is intended that the scope of patent protection is to be defined by the issued claim(s) rather than the description set forth herein.
Additionally, it is important to note that each term used herein refers to that which an ordinary artisan would understand such a term to mean based on the contextual use of the term herein. To the extent that the meaning of a term used herein—as understood by the ordinary artisan based on the contextual use of such term—differs in any way from any particular dictionary definition of such term, it is intended that the meaning of the term as understood by the ordinary artisan should prevail.
Regarding applicability of 35 U.S.C. § 112, ¶16, no claim element is intended to be read in accordance with this statutory provision unless the explicit phrase “means for” or “step for” is actually used in such claim element, whereupon this statutory provision is intended to apply in the interpretation of such claim element.
Furthermore, it is important to note that, as used herein, “a” and “an” each generally denotes “at least one,” but does not exclude a plurality unless the contextual use dictates otherwise. When used herein to join a list of items, “or” denotes “at least one of the items,” but does not exclude a plurality of items of the list. Finally, when used herein to join a list of items, “and” denotes “all of the items of the list.”
The following detailed description refers to the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the following description to refer to the same or similar elements. While many embodiments of the disclosure may be described, modifications, adaptations, and other implementations are possible. For example, substitutions, additions, or modifications may be made to the elements illustrated in the drawings, and the methods described herein may be modified by substituting, reordering, or adding stages to the disclosed methods. Accordingly, the following detailed description does not limit the disclosure. Instead, the proper scope of the disclosure is defined by the appended claims. The present disclosure contains headers. It should be understood that these headers are used as references and are not to be construed as limiting upon the subject matter disclosed under the header.
In refrigeration and cooling systems, a persistent challenge exists in achieving efficient heat transfer while minimizing energy consumption. Conventional refrigeration systems typically rely on mechanical vapor compression cycles that utilize synthetic refrigerants operating under high pressure conditions. These systems face several significant technical problems that limit their efficiency and environmental sustainability.
One primary technical problem is the substantial energy consumption associated with traditional compression-based refrigeration. Conventional compressors may consume a significant amount of electrical power during operation, contributing to high operational costs and environmental impact. Moreover, the compression process itself generates additional heat, which can increase the total heat load by up to 25%, further reducing system efficiency. This inefficiency is particularly problematic in applications requiring continuous cooling, such as data centers, where energy costs represent a major operational expense.
Another technical challenge involves the high operating pressures required in conventional refrigeration systems. These systems often operate at pressures exceeding 400 PSI, necessitating robust components and complex designs that increase manufacturing costs, maintenance requirements, and failure risks. The high-pressure operation also creates safety concerns related to potential refrigerant leaks and system failures.
Environmental considerations present additional challenges. Many conventional refrigeration systems utilize synthetic refrigerants with significant global warming potential. These refrigerants may contribute to climate change when released into the atmosphere, leading to increasing regulatory restrictions on their use. The phase-out of various refrigerants has created a need for alternative cooling technologies that can provide efficient cooling while minimizing environmental impact.
The management of refrigerants under varying operational demands also poses technical difficulties. Refrigerants need to be maintained under specific conditions to optimize performance, which can be difficult to achieve consistently with mechanical compression alone. Additionally, the phase change of refrigerants, crucial for heat absorption and release, may be less efficient under suboptimal conditions, impacting the overall efficiency of the refrigeration cycle.
In cascade refrigeration systems utilizing CO2 as a low-stage refrigerant, maintaining subcritical operation regardless of ambient conditions presents a particular challenge. When ambient temperatures rise, conventional systems may struggle to keep CO2 in a subcritical state, reducing efficiency and increasing energy consumption. This limitation is especially problematic in warm climates or during summer months when cooling demands are highest.
The water vapor refrigeration system described herein addresses the technical problems associated with conventional refrigeration by utilizing water as a refrigerant in a vacuum-based system. This approach may eliminate the need for traditional compressors, reduce energy consumption, operate at lower pressures, and provide an environmentally friendly alternative to synthetic refrigerants.
The system may include several interconnected components that work synergistically to provide efficient cooling. A fluid tank may store a supply of fluid that serves as the primary refrigerant. A fluid pump fluidly coupled to the fluid tank may circulate fluid throughout the system. The fluid pump may feature a variable flow rate capability to control the volume of fluid supplied based on operational demands.
An eductor in fluid communication with the fluid pump may create a vacuum by utilizing the fluid flow. The eductor may comprise a specialized nozzle designed to maximize pressure reduction, achieving the desired boiling point of the fluid for efficient heat absorption. This vacuum creation may be a key factor in enabling the fluid to function effectively as a refrigerant. In particular, the vacuum may allow for water to function as the fluid. Additionally or alternatively, the fluid may be at least one of ammonia, carbon dioxide, or a synthetic refrigerant.
A vacuum chamber fluidly connected to the eductor may facilitate the evaporation of fluid under vacuum conditions. This evaporation process may absorb heat from a refrigerant, thereby providing the cooling effect. The vacuum chamber may include a float mechanism to maintain a predetermined fluid level, ensuring consistent evaporation.
A heat exchanger in thermal communication with the vacuum chamber may transfer heat from the refrigerant to the evaporated fluid. The heat exchanger may be specifically configured for use with CO2 refrigerant in a subcritical state, with the cooling effect of the evaporated fluid facilitating this subcritical operation regardless of ambient temperature conditions.
A condenser fluidly connected to the vacuum chamber may condense the evaporated fluid and discharge the heat absorbed from the refrigerant. The condenser may be equipped with a heat rejection unit capable of transferring heat to an external environment or a secondary heat utilization system, potentially allowing for heat recovery applications.
The system may further include a control unit programmed to monitor and adjust various operational parameters, including pressure within the vacuum chamber, flow rate of the fluid pump, and temperature of the condenser. This control unit may optimize system performance based on changing environmental conditions and cooling demands.
A vapor separation tank may be positioned between the eductor and the fluid tank. This tank may be configured to separate entrained liquid from vapor, enhancing the efficiency of the heat transfer process. The separation of liquid and vapor phases may be crucial for maintaining optimal system operation.
The system may be configured to operate as a high stage in a cascade refrigeration system with a secondary refrigerant circuit. This configuration may be particularly advantageous when used with CO2 as the low-stage refrigerant, as the fluid vapor system may maintain subcritical CO2 conditions regardless of ambient temperatures.
In some embodiments, a liquid ring vacuum pump may be incorporated as an alternative mechanism for maintaining vacuum within the vacuum chamber. This alternative may provide flexibility in system design and operation, particularly for higher-capacity applications.
The heat exchanger may be adapted to facilitate heat exchange between the evaporated fluid and a secondary refrigerant in a cascade refrigeration cycle. This arrangement may enhance the system's versatility and applicability across various cooling scenarios.
Multiple sensors may be integrated throughout the system for real-time monitoring of temperature, pressure, and fluid flow rates. These sensors may provide data to the control unit, enabling precise adjustments to maintain optimal performance.
A bypass valve system may allow for selective isolation of components during maintenance operations, minimizing system downtime and facilitating service procedures. This feature may enhance the system's reliability and serviceability in commercial and industrial applications.
The present disclosure includes many aspects and features. Moreover, while many aspects and features relate to, and are described in, the context of a water vapor refrigeration system, embodiments of the present disclosure are not limited to use only in this context.

I. Platform Overview

This overview is provided to introduce a selection of concepts in a simplified form that are further described below. This overview is not intended to identify key features or essential features of the claimed subject matter. Nor is this overview intended to be used to limit the claimed subject matter's scope.
The water vapor refrigeration system represents an innovative approach to cooling that utilizes water as a refrigerant in a vacuum environment. Unlike conventional refrigeration systems that rely on mechanical vapor compression cycles with synthetic refrigerants operating under high pressure conditions, this system harnesses the exceptional thermal properties of water, particularly its high latent heat of vaporization (970 BTU/lb), to achieve efficient cooling while minimizing energy consumption.
The system operates by creating a deep vacuum that allows water to boil at low temperatures (as low as 25° F.), enabling it to effectively absorb heat from the medium to be cooled. This process occurs without traditional mechanical compression, which typically accounts for approximately 25% of the total energy consumption in conventional refrigeration systems.
The water vapor refrigeration system consists of several key components working together in a closed-loop configuration. A water tank serves as the primary reservoir for the refrigerant. A water pump circulates water from this tank throughout the system. An eductor, utilizing the flow of water from the pump, creates the necessary vacuum conditions. A vacuum chamber facilitates the evaporation of water under these vacuum conditions, allowing it to absorb heat from a refrigerant or directly from the environment to be cooled. A heat exchanger transfers heat from the medium to be cooled to the evaporated water. Finally, a condenser condenses the water vapor back to liquid form and discharges the absorbed heat.
One application of this system is at the high stage in a cascade refrigeration configuration, particularly with CO2 as the low stage refrigerant. By maintaining the CO2 in a subcritical state regardless of ambient conditions, the system achieves greater efficiency than conventional refrigeration systems.
The system offers numerous advantages over traditional cooling technologies. It uses water, which is environmentally friendly, non-toxic, and has zero global warming potential, unlike synthetic refrigerants. It operates at sub-atmospheric pressures rather than the high pressures (often exceeding 400 PSI) typical in conventional systems, reducing structural requirements and eliminating risks associated with high-pressure refrigerant leaks. The elimination of traditional compressors and oil management systems significantly reduces system complexity, maintenance requirements, and failure risks.
The water vapor refrigeration system can be adapted for various applications, including commercial and industrial refrigeration, food processing facilities, pharmaceutical manufacturing, data centers, building climate control systems, and process cooling applications. Its versatility and efficiency make it a promising solution for addressing the growing demand for environmentally sustainable and energy-efficient cooling technologies. In some embodiments, the system may also be adapted for use with other fluid refrigerants, including (but not limited to) at least one of ammonia, carbon dioxide, or a synthetic refrigerant.
Embodiments of the present disclosure may comprise methods, systems, and a computer readable medium comprising, but not limited to, at least one of the following:

- A. A Fluid Storage Tank
- B. A Fluid Pump
- C. An Eductor
- D. An Evaporator
- E. A Vacuum Chamber
- F. A Heat Exchanger
- G. A Condenser
- H. A Vapor Separation Tank
- I. A Control Unit

The fluid tank 102 may be configured to store a supply of fluid that serves as the primary refrigerant in the refrigeration system 100. The fluid tank 102 may be constructed from materials suitable for containing the fluid under various temperature and pressure conditions, such as stainless steel, carbon steel with appropriate coatings, or high-grade polymers. The tank 102 may be sized according to the cooling capacity requirements of the system 100, with larger systems requiring correspondingly larger fluid storage capacity.
Details with regards to each module are provided below. Although modules are disclosed with specific functionality, it should be understood that functionality may be shared between modules, with some functions split between modules, while other functions duplicated by the modules. Furthermore, the name of each module should not be construed as limiting upon the functionality of the module. Moreover, each component disclosed within each module can be considered independently, without the context of the other components within the same module or different modules. Each component may contain functionality defined in other portions of this specification. Each component disclosed for one module may be mixed with the functionality of other modules. In the present disclosure, each component can be claimed on its own and/or interchangeably with other components of other modules.
The following depicts an example of a method of a plurality of methods that may be performed by at least one of the aforementioned modules, or components thereof. Various hardware components may be used at the various stages of the operations disclosed with reference to each module.
Furthermore, although the stages of the following example method are disclosed in a particular order, it should be understood that the order is disclosed for illustrative purposes only. Stages may be combined, separated, reordered, and various intermediary stages may exist. Accordingly, it should be understood that the various stages, in various embodiments, may be performed in orders that differ from the ones disclosed below. Moreover, various stages may be added or removed without altering or departing from the fundamental scope of the depicted methods and systems disclosed herein.
Consistent with embodiments of the present disclosure, a method may be performed by at least one of the modules disclosed herein. The method may be embodied as, for example, but not limited to, computer instructions which, when executed, perform the method. The method may comprise the following stages:

- circulating fluid from a fluid tank through a fluid pump;
- directing the fluid through an eductor to create a vacuum;
- transferring the fluid under vacuum to a vacuum chamber where the fluid is evaporated to absorb heat from a medium to be cooled;
- conveying the evaporated fluid to a condenser where the fluid is condensed; and
- returning the condensed fluid to the fluid tank.

Both the foregoing overview and the following detailed description provide examples and are explanatory only. Accordingly, the foregoing overview and the following detailed description should not be considered to be restrictive. Further, features or variations may be provided in addition to those set forth herein. For example, embodiments may be directed to various feature combinations and sub-combinations described in the detailed description.

II. Platform Configuration

A water vapor refrigeration system represents a significant advancement in cooling technology. The system utilizes water as a refrigerant in a vacuum environment, harnessing water's exceptional thermal properties, particularly its high latent heat of vaporization (approximately 970 BTU/lb), to achieve efficient cooling while minimizing energy consumption.
Unlike conventional refrigeration systems that rely on mechanical vapor compression cycles with synthetic refrigerants operating under high pressure conditions, the water vapor refrigeration system operates at sub-atmospheric pressures. This fundamental difference eliminates the need for traditional compressors, which typically account for approximately 60-80% of the total energy consumption in conventional refrigeration systems and generate additional heat that increases the overall heat load.
The water vapor refrigeration system may comprise several interconnected components that work synergistically to provide efficient cooling. A water tank may store a supply of water that serves as the primary refrigerant. A water pump fluidly coupled to the water tank may circulate water throughout the system with variable flow rate capability to control the volume of water supplied based on operational demands.
An eductor in fluid communication with the water pump may create a vacuum by utilizing the flow of water. The eductor may comprise a specialized nozzle designed to maximize pressure reduction, achieving the desired boiling point of water for efficient heat absorption. This vacuum creation may be a key factor in enabling water to function effectively as a refrigerant.
A vacuum chamber fluidly connected to the eductor may facilitate the evaporation of water under vacuum conditions. This evaporation process may absorb heat from a refrigerant, thereby providing the cooling effect. The vacuum chamber may include a float mechanism to maintain a predetermined water level, ensuring consistent evaporation.
A heat exchanger in thermal communication with the vacuum chamber may transfer heat from the refrigerant to the evaporated water. The heat exchanger may be specifically configured for use with CO2 refrigerant in a subcritical state, with the cooling effect of the evaporated water facilitating this subcritical operation regardless of ambient temperature conditions.
A condenser fluidly connected to the vacuum chamber may condense the evaporated water and discharge the heat absorbed from the refrigerant. The condenser may be equipped with a heat rejection unit capable of transferring heat to an external environment or a secondary heat utilization system, potentially allowing for heat recovery applications.
The system may further include a control unit programmed to monitor and adjust various operational parameters, including pressure within the vacuum chamber, flow rate of the water pump, and temperature of the condenser. This control unit may optimize system performance based on changing environmental conditions and cooling demands.
A vapor separation tank may be positioned between the eductor and the vacuum chamber. This tank may be configured to separate entrained liquid from vapor, enhancing the efficiency of the heat transfer process. The separation of liquid and vapor phases may be crucial for maintaining optimal system operation.
The system may be configured to operate as a high stage in a cascade refrigeration system with a secondary refrigerant circuit. This configuration may be particularly advantageous when used with CO2 as the low-stage refrigerant, as the water vapor system may maintain subcritical CO2 conditions regardless of ambient temperatures.
In some embodiments, a liquid ring vacuum pump or similar device may be incorporated as an alternative mechanism for maintaining vacuum within the vacuum chamber. This alternative may provide flexibility in system design and operation, particularly for higher-capacity applications.
The water vapor refrigeration system offers numerous advantages over conventional cooling technologies, including environmental sustainability through the use of water as a refrigerant with zero global warming potential, enhanced safety due to sub-atmospheric operating pressures, reduced maintenance requirements through elimination of oil management systems, and significant energy efficiency improvements.
The system may be adapted for various applications, including commercial and industrial refrigeration, food processing facilities, pharmaceutical manufacturing, data centers, building climate control systems, and process cooling applications. Its versatility and efficiency make it a promising solution for addressing the growing demand for environmentally sustainable and energy-efficient cooling technologies.
The water vapor refrigeration system may operate in a variety of environments where efficient cooling is required. These environments may include commercial refrigeration facilities, industrial cooling applications, data centers, food processing plants, pharmaceutical manufacturing facilities, and building climate control systems.
The system may be designed to function effectively across a range of ambient temperatures and humidity conditions. In hot climates, where conventional refrigeration systems often struggle with efficiency due to high condensing temperatures, the water vapor refrigeration system may maintain consistent performance by leveraging the vacuum-based evaporation process that is less affected by ambient temperature fluctuations.
The system may utilize a stable power supply to operate the water pump and any auxiliary components such as control systems and sensors. The power requirements may be significantly lower than conventional compression-based refrigeration systems due to the elimination of energy-intensive compressors.
The system may be installed in indoor environments with adequate ventilation to ensure proper heat rejection from the condenser. The installation space may need to accommodate the water tank, pump, eductor, vacuum chamber, heat exchanger, and condenser, with appropriate clearances for maintenance access. The system may be configured in various layouts to adapt to space constraints, with the possibility of remote placement of certain components such as the condenser.
Water quality may be an important consideration for the operating environment. The system may function optimally with treated water to prevent scale buildup or corrosion within the components. In environments where water quality is poor, a water treatment system may be incorporated to ensure long-term reliability and efficiency.
The water vapor refrigeration system may be particularly well-suited for environments where environmental considerations are paramount. Unlike conventional refrigeration systems that use synthetic refrigerants with significant global warming potential, the water-based system may offer a sustainable alternative with zero ozone depletion potential and zero global warming potential.
In cascade refrigeration applications, the water vapor system may serve as the high stage, interfacing with a CO2 low stage. This configuration may require an environment capable of accommodating both systems, with appropriate connections between them. The operating environment may need to support the subcritical operation of CO2, which may be maintained by the cooling effect of the water vapor system regardless of ambient conditions.
For data center applications, the system may be integrated with existing cooling infrastructure, potentially replacing or supplementing conventional computer room air conditioning (CRAC) units. The water vapor system may be particularly advantageous in this environment due to its energy efficiency and ability to provide precise temperature control.
In food processing and pharmaceutical manufacturing environments, the system may need to comply with industry-specific regulations regarding temperature control and system reliability. The water vapor refrigeration system may be configured with redundant components and backup systems to ensure continuous operation in these critical applications.
The control system of the water vapor refrigeration system may be designed to interface with building management systems (BMS) or industrial control systems. This integration may allow for centralized monitoring and control of the refrigeration system alongside other building or facility systems. The operating environment may therefore include the necessary network infrastructure to support this communication.
In environments with variable cooling loads, the system may be designed with modular components that can be activated or deactivated based on demand. This flexibility may allow the system to maintain efficiency across a wide range of operating conditions, from partial to full load.
The water vapor refrigeration system may also be suitable for environments where heat recovery is desired. The heat rejected from the condenser may be captured and utilized for space heating, domestic hot water, or process heating applications, enhancing the overall energy efficiency of the facility.
For cascade refrigeration applications with CO2 as the low stage refrigerant, the system may be designed to maintain CO2 temperatures no higher than 75° F. to ensure subcritical operation. This temperature control may be critical for the efficiency and reliability of the overall refrigeration system.
The water pump may operate at pressures ranging from 75 to 135 psi and flow rates of 75 to 135 gpm, depending on the cooling capacity required and the specific configuration of the system. The operating environment may need to support these pressure and flow requirements, with appropriate piping and electrical infrastructure.
In summary, the water vapor refrigeration system may be adaptable to a wide range of operating environments, offering energy-efficient and environmentally friendly cooling solutions across various applications. The specific requirements of each environment may be addressed through careful system design and configuration, ensuring optimal performance and reliability.
As shown in FIGS. 1-3 , a water vapor refrigeration system 100 may include several interconnected components working together to provide efficient cooling. The system 100 may utilize water as a refrigerant, leveraging its high latent heat of vaporization to achieve superior cooling performance while minimizing energy consumption.
The system 100 may include a water tank 102, which may serve as a reservoir for storing the water supply used in the refrigeration cycle. This tank 102 may be designed to maintain a sufficient volume of water to ensure continuous operation of the system. The tank 102 may include a level monitoring system 104 to ensure adequate water levels are maintained during operation.
A water pump 106 may be fluidly coupled to the water tank 102 and configured to circulate water throughout the system 100. The water pump 106 may feature variable flow rate capabilities, allowing for adjustment based on cooling demands. This variability may enhance efficiency of the system 100 by providing only the necessary flow for current operating conditions. The pump 106 may operate at various pressures and flow rates. As one non-limiting example, the pump 106 may operate at pressures ranging from about 75 to about 135 psi and flow rates of about 75 to about 135 gpm, depending on system requirements. Flow rates may be determined based at least in part on the specific requirements of the size of eductor being used.
An eductor 108 may be positioned in fluid communication with the water pump 106. The eductor 108 may create a vacuum by utilizing the flow of water from the pump 106 through a specially-designed nozzle. This nozzle may be specifically engineered to maximize pressure reduction, achieving the desired vacuum level for operation. The vacuum created may enable water to boil at lower temperatures, facilitating the refrigeration process without traditional compression methods.
A vacuum chamber 112 may be fluidly connected to the eductor 108, structured to facilitate the evaporation of water under vacuum conditions. This chamber 112 may be designed to maintain precise vacuum levels. For example, the vacuum level may be maintained under 1000 microns, allowing water to absorb heat from a refrigerant through phase change. The vacuum chamber 112 may include a float mechanism 114 to maintain a predetermined water level, ensuring consistent evaporation rates and system performance.
A heat exchanger 116 may be positioned in thermal communication with the vacuum chamber 112. The heat exchanger 116 may be configured to transfer heat from the refrigerant to the evaporated water. In some embodiments, the heat exchanger 116 may be specifically designed for use with CO2 refrigerant in a subcritical state, with the cooling effect of the evaporated water facilitating this subcritical operation regardless of ambient temperature conditions. Various heat exchanger configurations may be employed, including (but not limited to) plate and frame, tube and shell, or tube in tube designs, depending on specific application requirements.
A condenser 118 may be fluidly connected to the vacuum chamber 112, configured to condense the evaporated water and discharge the heat absorbed from the refrigerant. The condenser 118 may be equipped with a heat rejection unit capable of transferring heat to an external environment or a secondary heat utilization system. This may allow for potential heat recovery applications, enhancing overall system efficiency.
A vapor separation tank 120 may be positioned between the eductor 108 and the vacuum chamber 112. This tank 120 may be configured to separate entrained liquid from vapor, enhancing the efficiency of the heat transfer process. The tank 120 may include internal baffles designed to enhance the separation process and may feature a float valve for automatic regulation of the liquid level within the tank.
The system 100 may include a control unit 122 programmed to monitor and adjust various operational parameters. This control unit 122 may receive input from multiple sensors throughout the system, measuring parameters such as temperature, pressure, flow rates, and/or the like. Based on these parameters, the control unit 122 may adjust the water pump speed, eductor operation, condenser performance, and or operation of any other component of the system 100 to optimize or otherwise improve system efficiency under varying conditions.
A subcooling unit 124 may be positioned downstream of the condenser 118 for additional cooling of the condensed water prior to its return to the system. This subcooling may enhance the efficiency of subsequent cooling cycles by reducing the energy required for evaporation.
In cascade refrigeration applications, the water vapor system may serve as the high stage, interfacing with a CO2 low stage. This configuration may maintain the CO2 in a subcritical state regardless of ambient conditions, which may significantly improve overall system efficiency compared to traditional cascade systems.
The system 100 may incorporate a liquid ring vacuum pump as an alternative mechanism for maintaining vacuum within the vacuum chamber. This alternative may provide flexibility in system design and operation, particularly for higher-capacity applications where performance of the eductor 108 might be limited.
A bypass valve system may allow for selective isolation of components during maintenance operations. This feature may minimize system downtime and facilitate service procedures without requiring complete system shutdown.
The system 100 may include a user interface for manual control and monitoring of operational status. This interface may provide real-time data on system performance, allowing operators to make adjustments as needed or to diagnose potential issues quickly.
A data recording system may log operational data for subsequent analysis and system optimization. This data may be used to identify trends, optimize performance parameters, and predict maintenance needs before failures occur.
The refrigeration system may be configurable to operate in multiple modes to accommodate varying environmental conditions and cooling load requirements. These modes may be automatically selected based on ambient conditions, cooling demands, or user preferences.
Remote communication capabilities may enable off-site system monitoring and diagnostics. This feature may allow for proactive maintenance, remote troubleshooting, and performance optimization without requiring on-site personnel.
The water vapor refrigeration system 100 may be adaptable for various applications, including commercial and industrial refrigeration, food processing facilities, pharmaceutical manufacturing, data centers, building climate control systems, and process cooling applications. The system's versatility and efficiency may make it a promising solution for addressing the growing demand for environmentally sustainable and energy-efficient cooling technologies.
The hardware necessary to enable the water vapor refrigeration system 100 includes several components that work together to create an efficient cooling solution. These components are described in detail below. Accordingly, embodiments of the present disclosure provide a software and hardware platform comprised of a distributed set of computing elements, including, but not limited to:

A. A Fluid Tank

The fluid tank 102 may be configured to store a supply of water or other fluid (e.g., at least one of ammonia, carbon dioxide, or a synthetic refrigerant) that serves as the primary refrigerant in the refrigeration system 100. The fluid tank 102 may be constructed from materials suitable for containing the fluid under various temperature and pressure conditions, such as stainless steel, carbon steel with appropriate coatings, or high-grade polymers. The tank 102 may be sized according to the cooling capacity requirements of the system 100, with larger systems requiring correspondingly larger fluid storage capacity.
The fluid tank 102 may include a level monitoring system 104 to ensure adequate fluid levels are maintained during operation. This level monitoring system 104 may comprise float switches, ultrasonic sensors, and/or pressure transducers that continuously measure the fluid level within the tank 102. The level monitoring system 104 may be electronically connected to the control unit 122, allowing for automated fluid level management and system protection against low fluid conditions.
In some embodiments, the fluid tank 102 may be insulated to minimize heat transfer between the stored fluid and the ambient environment. This insulation may help maintain consistent fluid temperatures and improve overall system efficiency by reducing unwanted thermal influences.
The fluid tank 102 may be equipped with inlet and outlet ports positioned to optimize fluid circulation and prevent stagnation. The inlet port may be located to allow returning condensed fluid to enter the tank 102 with minimal turbulence, while the outlet port may be positioned to ensure consistent fluid supply to the fluid pump 106 without introducing air into the system.
A filtration system may optionally be incorporated within or connected to the fluid tank 102 to maintain fluid quality by removing particulates and contaminants that could potentially affect system performance and/or damage components. This filtration system may include replaceable filter elements that can be serviced during routine maintenance.
The fluid tank 102 may feature access ports or hatches to facilitate inspection, cleaning, and maintenance of the internal surfaces. These access points may be sealed with appropriate gaskets to prevent fluid leakage during operation.
In certain configurations, the fluid tank 102 may include baffles or dividers to reduce fluid movement during operation, particularly in mobile applications where the system 100 might be subject to motion. These internal structures may help prevent fluid sloshing that could potentially disrupt the consistent flow to the fluid pump 106.
The fluid tank 102 may be equipped with temperature sensors to monitor the fluid temperature, providing data to the control unit 122 for system optimization. Maintaining appropriate fluid temperature in the tank 102 may be crucial for efficient operation of the refrigeration cycle.
In some embodiments, the fluid tank 102 may include a heating element controlled by the control unit 122 to prevent freezing in cold ambient conditions when the system 100 is not in operation. This heating element may be activated automatically based on temperature readings from sensors within or near the tank 102.
The fluid tank 102 may be designed with overflow protection and drainage features to manage excess fluid and prevent system flooding. These features may include overflow pipes, drain valves, or automatic shut-off mechanisms triggered by the level monitoring system 104.
For systems designed for outdoor installation, the fluid tank 102 may be constructed with UV-resistant materials or coatings to prevent degradation from sun exposure. Additionally, the tank 102 may be designed to withstand various weather conditions, including extreme temperatures, precipitation, and humidity.
The fluid tank 102 may be mounted on a stable platform or base to ensure proper support and to minimize vibration during operation. In some installations, vibration isolation mounts may be used to reduce noise transmission and prevent stress on the tank 102 and connected components.
In some embodiments, the fluid tank 102 may include advanced filtration systems to maintain fluid quality and prevent scale buildup or corrosion within the system components. These filtration systems may include, as non-limiting examples, replaceable filter elements, fluid treatment technologies, and automatic purge mechanisms to remove contaminants from the fluid supply.

B. A Fluid Pump

The fluid pump 106 may be fluidly coupled to the fluid tank 102. The fluid pump 106 may be configured to circulate water or other fluid (e.g., at least one of ammonia, carbon dioxide, or a synthetic refrigerant) throughout the system 100. The fluid pump 106 may feature variable flow rate capabilities, allowing for adjustment based on cooling demands and/or other factors. This variability may enhance efficiency of the system 100 by providing only the necessary flow for current operating conditions.
The pump 106 may operate at various pressures and flow rates. In one non-limiting example, the pump 106 may operate at pressures ranging from about 75 to about 135 psi and flow rates of about 75 to about 135 gpm, depending on system requirements. The fluid pump 106 may include multiple pumping stages to achieve optimal pressure for eductor operation.
The fluid pump 106 may be characterized by a variable flow rate to control the volume of fluid supplied to the eductor 108 based on operational demands of the system 100. This control may be facilitated through a variable frequency drive that adjusts the pump speed according to system requirements. The variable frequency drive may receive signals from the control unit 122 based on data from pressure and temperature sensors throughout the system.
In some embodiments, the fluid pump 106 may be a centrifugal pump designed for continuous operation with minimal maintenance requirements. The pump 106 may be constructed from materials compatible with the fluid. For example, where the fluid is water, the materials may be stainless steel or corrosion-resistant alloys, to ensure longevity and reliable performance. The pump housing may be designed to withstand the operating pressures while minimizing vibration and noise during operation.
The fluid pump 106 may include a mechanical seal system to prevent fluid leakage around the pump shaft. This seal system may be designed for long-term operation without requiring frequent maintenance or replacement. In some configurations, the pump 106 may incorporate a double mechanical seal with a barrier fluid for enhanced reliability in continuous operation.
The inlet of the fluid pump 106 may be positioned to ensure adequate submersion in the fluid tank 102, preventing air entrainment that could lead to cavitation and reduced pumping efficiency. The pump 106 may include a strainer or filter at its inlet to prevent debris from entering and potentially damaging the pump impeller or other components.
The discharge side of the fluid pump 106 may be equipped with a check valve to prevent backflow when the pump is not operating. This check valve may help maintain system pressure and prevent fluid from flowing back into the fluid tank 102 when the system is in standby mode.
The fluid pump 106 may be mounted on vibration isolation pads to reduce the transmission of vibration to the surrounding structure. This isolation may help extend the operational life of the pump and reduce noise during system operation.
In some embodiments, the fluid pump 106 may include temperature and pressure sensors at both the inlet and outlet. These sensors may provide data to the control unit 122 for monitoring pump performance and detecting potential issues before they lead to system failures.
The fluid pump 106 may be sized according to the cooling capacity requirements of the system 100, with larger systems requiring correspondingly higher flow rates and pressures. The pump selection may be based on the specific pressure drop characteristics of the eductor 108 and other components in the fluid circulation path.
For systems designed for outdoor installation, the fluid pump 106 may be housed in a weather-resistant enclosure to protect it from environmental factors such as precipitation, dust, and extreme temperatures. This enclosure may include ventilation to prevent overheating of the pump motor during operation.
In some embodiments, the fluid pump 106 may include multiple pumping stages to achieve optimal pressure for eductor operation. This multi-stage approach may provide more precise control over the pressure and flow rate of fluid supplied to the eductor 108, enhancing the efficiency of vacuum creation and the overall performance of the system 100.

C. An Eductor

The eductor 108 may be positioned in fluid communication with the fluid pump 106. The eductor 108 may be configured to create a vacuum by utilizing the flow of fluid from the pump 106 through a specially-designed nozzle. This nozzle may be specifically engineered to maximize pressure reduction, achieving the desired vacuum level for operation of the refrigeration system 100. The vacuum created by the eductor 108 may enable fluid to boil at lower temperatures, facilitating the refrigeration process without traditional compression methods.
The eductor 108 may employ the venturi effect to create and maintain the necessary vacuum conditions. As fluid flows through the narrowed section of the nozzle, its velocity increases while its pressure decreases, creating a low-pressure zone that draws in vapor from the vacuum chamber 112. This vacuum generation mechanism operates according to Bernoulli's principle, wherein the increased kinetic energy of the fluid flowing through the constricted section results in a corresponding decrease in pressure. The magnitude of vacuum created may be controlled by adjusting the flow rate and pressure of the fluid supplied to the eductor 108, with higher flow rates typically producing stronger vacuum conditions.
As one example, where the fluid is water, the vacuum created by the eductor 108 may be maintained at a level sufficient to lower the boiling point of water to approximately 25° F., enabling efficient heat absorption from the refrigerant. This low-pressure environment may be crucial for the system's operation as it allows water to change phase from liquid to vapor at temperatures well below its standard boiling point, thereby enhancing its capacity to absorb heat from the refrigerant. The eductor 108 may continuously extract vapor from the vacuum chamber 112, maintaining the pressure differential necessary for sustained evaporation and heat transfer processes within the system 100.
In some embodiments, the eductor 108 may include multiple parallel eductors configured to operate selectively based on cooling load requirements. This configuration may allow for greater flexibility in system operation, enabling the system 100 to adapt to varying cooling demands by activating or deactivating individual eductors as needed.
The eductor 108 may be constructed from materials resistant to corrosion and suitable for continuous operation with water as both the motive fluid and refrigerant. These materials may include stainless steel, high-grade polymers, or other corrosion-resistant alloys that can withstand the operating conditions of the system 100.
The nozzle of the eductor 108 may feature a precision-engineered profile designed to optimize the pressure reduction while minimizing energy losses. The geometry of the nozzle may be specifically tailored to achieve the desired vacuum levels with the available fluid pressure and flow rate from the pump 106.
The eductor 108 may include an inlet port connected to the fluid pump 106, a suction port connected to the vacuum chamber 112, and a discharge port that directs the combined flow of motive fluid and entrained vapor to the vapor separation tank 120. The inlet port may be sized to accommodate the flow rate provided by the fluid pump 106, while the suction port may be designed to efficiently draw vapor from the vacuum chamber 112.
In some embodiments, the eductor 108 may include adjustable features that allow for fine-tuning of its performance. These features may include replaceable nozzles with different geometries or adjustable throat sections that can be modified to optimize vacuum creation under varying operating conditions.
The eductor 108 may be mounted in a position that minimizes the length of piping between it and the vacuum chamber 112, reducing pressure losses and enhancing the efficiency of the vacuum creation process. The mounting may also include vibration isolation to prevent the transmission of vibrations to other components of the system 100.
The connection between the eductor 108 and the fluid pump 106 may include a pressure gauge to monitor the inlet pressure, ensuring that it remains within the optimal range for efficient operation of the eductor 108. Similarly, a vacuum gauge may be installed at the suction port to monitor the vacuum level being created.
In alternative embodiments, the system 100 may utilize a liquid ring vacuum pump instead of the eductor 108 for creating and maintaining the vacuum within the vacuum chamber 112. This alternative may be particularly suitable for higher-capacity applications where the performance of the eductor 108 might be limited.
The eductor 108 may be designed with interchangeable nozzles in certain embodiments, allowing for field adjustment of the vacuum level based on specific application requirements. This feature may enhance the adaptability of the system to varying operational conditions and cooling demands.
The system 100 may be configured with multiple eductors 108, with each individual eductor 108 being selectively activated. As one example, the eductors 108 may be activated based on cooling load requirements. Each eductor 108 may be equipped with individual control valves, allowing for precise adjustment of the vacuum level and flow rate. This modular approach may enable the system to adapt to varying cooling demands more effectively, activating only the number of eductors 108 needed to meet the current load requirements. As another example, independent eductors 108 (e.g., an evaporator eductor and a condenser eductor) may allow for contemporaneous operation of both a hydrovaporization refrigeration cycle (Cycle 1) and an auto-impelled deep vacuum generation cycle (Cycle 2), as described in more detail below.

D. An Evaporator

The evaporator 110 may be fluidly connected to the eductor 108 and configured to facilitate the evaporation of fluid (e.g., water, ammonia, carbon dioxide, or a synthetic refrigerant) under vacuum conditions. The evaporator 110 may be designed to provide an efficient heat exchange surface where fluid may absorb heat from a medium to be cooled. This absorption of heat may cause the water to change phase from liquid to vapor, creating the cooling effect that is central to the refrigeration system's operation.
The evaporator 110 may include a series of tubes or plates through which the medium to be cooled may flow, surrounded by the fluid refrigerant under vacuum conditions. The vacuum conditions within the evaporator 110 may be maintained by the eductor 108, allowing the fluid to boil at temperatures significantly lower than its standard boiling point at atmospheric pressure. This low-temperature boiling may enable effective heat absorption from the medium to be cooled, even when that medium is at relatively low temperatures itself.
In some embodiments, the evaporator 110 may be specifically designed for operation with CO2 as the medium to be cooled. The evaporator 110 may be configured to maintain the CO2 in a subcritical state regardless of ambient temperature conditions, which may be particularly advantageous for the overall efficiency of the refrigeration system. The heat transfer surfaces within the evaporator 110 may be engineered to maximize the heat exchange between the CO2 and the fluid refrigerant.
The evaporator 110 may incorporate internal baffles or flow directors to ensure even distribution of the fluid refrigerant across the heat transfer surfaces. This even distribution may help prevent localized hot spots and ensure uniform cooling of the medium. The internal structure of the evaporator 110 may also be designed to minimize pressure drop while maximizing heat transfer efficiency.
The evaporator 110 may include a float mechanism to maintain a predetermined fluid level within the chamber. This float mechanism may help ensure consistent evaporation rates by maintaining an optimal amount of fluid in contact with the heat transfer surfaces. The float mechanism may be mechanically or electronically controlled to adjust the fluid level based on cooling demand and system conditions.
The materials used in the construction of the evaporator 110 may be selected for their corrosion resistance and thermal conductivity. As non-limiting examples, stainless steel, copper, and/or specialized alloys may be employed to help ensure longevity and efficiency of the heat transfer process. The materials may also be chosen to withstand the vacuum conditions present during operation without deformation or failure.
The evaporator 110 may include multiple temperature sensors positioned at strategic locations to monitor the temperature of both the fluid refrigerant and the medium being cooled. These sensors may provide data to the control unit 122, allowing for real-time adjustments to optimize the cooling process. Pressure sensors may also be incorporated to monitor the vacuum level within the evaporator 110, ensuring it remains within the desired range for efficient operation.
In some embodiments, the evaporator 110 may feature a modular design that allows for scaling of cooling capacity based on application requirements. Multiple evaporator units may be connected in parallel or series configurations to achieve the desired cooling capacity and temperature profile. This modular approach may provide flexibility in system design and installation.
The evaporator 110 may be thermally insulated to minimize unwanted heat gain from the surrounding environment. This insulation may help maintain the efficiency of the cooling process by ensuring that the majority of the heat absorbed by the fluid refrigerant comes from the intended medium rather than ambient conditions. The insulation may be selected based on the specific operating conditions and installation environment of the system.

E. A Vacuum Chamber

The vacuum chamber 112 may be fluidly connected to the eductor 108, wherein the vacuum chamber 112 may be structured to facilitate the evaporation of the fluid under vacuum conditions to absorb heat from a refrigerant. The vacuum chamber 112 may be designed to maintain precise vacuum levels, for example, under 1000 microns, allowing fluid to absorb heat from a refrigerant through phase change. The vacuum chamber 112 may include a float mechanism 114 to maintain a predetermined fluid level, ensuring consistent evaporation rates and system performance.
The vacuum chamber 112 may be specifically configured to maintain subcritical CO2 conditions regardless of ambient temperatures. This capability may be particularly advantageous when the system 100 is employed in cascade refrigeration applications, where maintaining the CO2 in a subcritical state can significantly improve overall system efficiency compared to traditional cascade systems.
The vacuum chamber 112 may be constructed from materials capable of withstanding negative pressure conditions, such as stainless steel, carbon steel with appropriate coatings, or high-grade polymers. The chamber 112 may include ports for vapor extraction and fluid movement and may incorporate level control mechanisms to ensure proper operation.
The vacuum chamber 112 may feature pressure monitoring and control elements to maintain the desired vacuum level. These elements may include pressure sensors that provide data to the control unit 122, allowing for automated adjustments to maintain optimal vacuum conditions. The chamber 112 may also include viewing ports or additional sensors for monitoring internal conditions during operation.
The vacuum chamber 112 may be configured with appropriate sealing mechanisms to maintain vacuum integrity. These sealing mechanisms may be designed to prevent air infiltration that could compromise the vacuum conditions necessary for efficient operation of the system 100.
In some embodiments, the vacuum chamber 112 may be designed with a multi-chamber configuration, featuring separate evaporation zones to enhance heat transfer efficiency. This design may allow for more precise control over the evaporation process and may improve the overall performance of the system 100.
The vacuum chamber 112 may be thermally insulated to minimize unwanted heat transfer between the chamber contents and the ambient environment. This insulation may help maintain consistent temperature conditions within the chamber 112, enhancing the efficiency of the heat absorption process.
In some embodiments, the vacuum chamber 112 may feature a multi-chamber design with separate evaporation zones. This design may enhance heat transfer efficiency (e.g., by creating optimized environments for different stages of the evaporation process). The multi-chamber approach may allow for more precise control over the evaporation process and improve the overall performance of the system.
The vacuum chamber 112 may optionally be equipped with enhanced insulation materials to help minimize or otherwise reduce unwanted heat transfer between the chamber contents and the ambient environment. This insulation may help maintain consistent temperature conditions within the chamber 112, enhancing the efficiency of the heat absorption process.

F. A Heat Exchanger

The heat exchanger 116 may be positioned in thermal communication with the vacuum chamber 112. The heat exchanger 116 may be configured to transfer heat from the refrigerant to the evaporated fluid. In some embodiments, the heat exchanger 116 may be specifically designed for use with CO2 refrigerant in a subcritical state, with the cooling effect of the evaporated fluid facilitating this subcritical operation regardless of ambient
The heat exchanger 116 may be constructed from materials with high thermal conductivity to maximize heat transfer efficiency. These materials may include copper, aluminum, stainless steel, or other metals and alloys with favorable thermal properties. The selection of materials may depend on factors such as compatibility with the refrigerants used, resistance to corrosion, and cost considerations.
Various heat exchanger configurations may be employed in the system 100, including (but not limited to) plate and frame, tube and shell, or tube in tube designs, depending on specific application requirements. The plate and frame configuration may offer advantages in terms of compactness and efficiency, while tube and shell designs may be preferred for certain pressure requirements and/or fluid characteristics.
The heat exchanger 116 may include enhanced surface features such as fins, corrugations, or microchannels to increase the effective heat transfer area. These features may significantly improve the overall heat transfer coefficient, allowing for more efficient operation and potentially smaller heat exchanger dimensions.
In embodiments where the heat exchanger 116 is specifically configured for use with CO2 refrigerant, it may be designed to withstand the operating pressures associated with CO2 systems while maintaining efficient heat transfer. The heat exchanger 116 may be sized according to the cooling capacity requirements of the system 100, with larger systems requiring correspondingly larger heat exchange surfaces.
The heat exchanger 116 may incorporate flow arrangements that optimize the temperature difference between the refrigerant and the evaporated fluid throughout the heat exchange process. Counter-flow arrangements, where the two fluids flow in opposite directions, may be particularly effective for maximizing heat transfer efficiency.
Temperature sensors may be installed at strategic locations on the heat exchanger 116 to monitor performance and provide data to the control unit 122. These sensors may enable real-time adjustments to system parameters to maintain optimal heat transfer conditions under varying loads and ambient conditions.
The heat exchanger 116 may be designed with serviceability in mind, incorporating features that facilitate cleaning and maintenance to prevent fouling or scaling that could reduce heat transfer efficiency over time. Access ports or removable sections may be included to allow for inspection and cleaning of heat transfer surfaces.
In cascade refrigeration applications, the heat exchanger 116 may serve as the interface between the fluid vapor system and the CO2 low stage. This configuration may allow the fluid vapor system to maintain the CO2 in a subcritical state regardless of ambient conditions, significantly improving overall system efficiency compared to traditional cascade systems.
The heat exchanger 116 may be implemented in various configurations beyond those previously described. A plate-type design specifically optimized for phase-change heat transfer under vacuum conditions may be employed in certain applications. This specialized heat exchanger 116 may maximize the contact area between the refrigerant and the evaporated fluid, enhancing thermal transfer efficiency.

G. A Condenser

The condenser 118 may be fluidly connected to the vacuum chamber 112, configured to condense the evaporated water and to discharge the heat absorbed from the refrigerant. The condenser 118 may be equipped with a heat rejection unit capable of transferring heat to an external environment or a secondary heat utilization system. This may allow for potential heat recovery applications, enhancing overall system efficiency.
The condenser 118 may include multiple condensing coils designed to maximize surface area contact with the vaporized refrigerant. These coils may be constructed from materials with high thermal conductivity, such as copper or aluminum, to enhance heat rejection efficiency. The arrangement of these coils may be optimized to ensure efficient heat transfer while minimizing pressure drop.
A fan assembly may be incorporated within the condenser 118 to facilitate the dissipation of heat from the condensing coils to the external environment. The fan speed may be variable and controlled by the control unit 122 based on condensing requirements and ambient conditions. This variable speed capability may allow for energy-efficient operation across a range of thermal loads.
The condenser 118 may also include fins attached to the condensing coils to increase the effective surface area for heat exchange. These fins may be designed with specific geometries to optimize airflow and heat transfer characteristics. The spacing and configuration of these fins may be tailored to balance heat transfer efficiency with air pressure drop considerations.
In some embodiments, the condenser 118 may incorporate a water spray system to aid in the condensation of the vaporized refrigerant. This spray system may be particularly beneficial in high ambient temperature conditions where additional cooling capacity may be required. The water spray may create an evaporative cooling effect that enhances the condenser's heat rejection capabilities.
Temperature sensors may be strategically placed within the condenser 118 to monitor the temperature of the refrigerant within the condensing coils. These sensors may provide data to the control unit 122, allowing for precise control of the condensing process. The control unit 122 may adjust fan speed, water spray rate, or other parameters based on these temperature readings to maintain optimal condensing conditions.
The condenser 118 may include a pressure relief valve to maintain safe operating pressures. This safety feature may prevent damage to the system in case of abnormal pressure conditions. The pressure relief valve may be designed to activate at a predetermined pressure threshold, releasing excess pressure while minimizing refrigerant loss.
For systems designed to operate with subcritical CO2 as the refrigerant, the condenser 118 may be specifically configured to handle the thermal characteristics of CO2. This may include specialized materials and design considerations to accommodate the operating pressures and heat transfer properties of CO2 refrigerant.
A condensate collection system may be incorporated within the condenser 118 for capturing and removing liquid refrigerant from the heat rejection unit. This system may ensure that condensed refrigerant is efficiently directed back into the refrigeration cycle. The collection system may include drainage channels, collection trays, and gravity-assisted flow paths to facilitate the movement of condensed refrigerant.
The condenser 118 may be designed as part of a closed-loop system that recirculates the condensed refrigerant within the refrigeration system. This closed-loop design may minimize refrigerant loss and enhance system efficiency. The condenser 118 may include appropriate connections and fittings to integrate seamlessly with other components of the refrigeration system.
In some embodiments, the condenser 118 may include a subcooling section for further cooling the condensed refrigerant below its saturation temperature. This subcooling may enhance the efficiency of the refrigeration cycle by increasing the cooling capacity of the refrigerant. The subcooling section may be integrated within the condenser unit or may be a separate component positioned downstream of the main condensing section.
The condenser 118 may be designed to facilitate the transfer of heat to a secondary medium, such as water or air. This feature may allow for the recovered heat to be utilized for other applications, such as space heating or water heating. The heat transfer mechanism may include a secondary heat exchanger within or connected to the condenser 118.
For systems requiring precise control of condensing conditions, the condenser 118 may include a bypass circuit for controlling the flow of refrigerant. This bypass may allow a portion of the refrigerant to bypass the condenser when full condensing capacity is not required. The bypass circuit may be controlled by the control unit 122 based on system demands and operating conditions.
The condenser 118 may be equipped with an insulation layer surrounding the condensing coils to minimize unwanted thermal losses. This insulation may help maintain the efficiency of the heat rejection process by preventing heat transfer to or from the surrounding environment. The insulation materials may be selected for their thermal properties, durability, and resistance to environmental factors.
In applications where the system is exposed to varying environmental conditions, the condenser 118 may be designed with features to maintain performance across a wide range of ambient temperatures. These features may include variable speed fans, adjustable louvers, or other mechanisms to adapt to changing conditions. The control unit 122 may adjust these features based on ambient temperature readings to optimize condenser performance.
In some embodiments, the system may incorporate a dual-circuit condenser 118 that allows for more efficient heat rejection. As one example, a first circuit may be dedicated to condensing the water vapor from the refrigeration cycle, while a second circuit may be used for subcooling the condensed water before it returns to the water tank. This approach may enhance the efficiency of the heat rejection process and improve the overall performance of the system.
In some embodiments, the condenser 118 may incorporate advanced heat rejection technologies such as (but not limited to) adiabatic cooling and/or microchannels to enhance efficiency. These technologies may improve the heat transfer rate between the vaporized water and the cooling medium, reducing the size and energy consumption of the condenser 118. The condenser 118 may utilize a vacuum system to pull the water vapor through the condenser tubing.

H. A Vapor Separation Tank

The vapor separation tank 120 may be positioned between the eductor 108 and the condenser 118 (as shown in FIG. 2 ). This tank 120 may be configured to separate entrained liquid from vapor, enhancing the efficiency of the heat transfer process. The separation of liquid and vapor phases may be crucial for maintaining optimal system operation.
The vapor separation tank 120 may include internal baffles designed to enhance the separation process. These baffles may create flow paths that facilitate the natural separation of vapor from liquid through gravitational effects. The baffles may be arranged in a configuration that maximizes separation efficiency while minimizing pressure drop through the tank 120.
A float valve may be incorporated within the vapor separation tank 120 for automatic regulation of the liquid level. This float valve may be mechanically linked to a control mechanism that adjusts the flow of liquid from the tank 120, ensuring that an optimal liquid level is maintained at all times. The float valve may be designed to operate reliably under the vacuum conditions present in the system 100.
The vapor separation tank 120 may feature a vapor outlet positioned at the top of the tank to direct separated vapor to the condenser 118. This outlet may be sized appropriately to accommodate the expected vapor flow rates under various operating conditions. The positioning of this outlet may be optimized to ensure that only vapor, free from entrained liquid, passes through to the vacuum chamber 112.
A liquid outlet may be located at the bottom of the vapor separation tank 120 to return separated liquid to the water tank 102 or to another appropriate point in the system 100. This outlet may include a trap or seal to prevent vapor from escaping through the liquid return path. The liquid return system may be designed to operate passively, using gravity to facilitate flow, or may incorporate a pump for systems where gravitational flow is not feasible.
The vapor separation tank 120 may be constructed from materials suitable for operation under vacuum conditions and compatible with water as the working fluid. These materials may include stainless steel, certain grades of aluminum, or high-performance polymers that can withstand the operational stresses while resisting corrosion or degradation.
Sight glasses or level indicators may be incorporated into the vapor separation tank 120 to allow for visual monitoring of the liquid level within the tank. These indicators may be positioned to provide clear visibility of critical liquid levels and may be integrated with the control system 122 to provide automated monitoring capabilities.
The vapor separation tank 120 may include temperature and pressure sensors to monitor the conditions within the tank. These sensors may provide data to the control unit 122, allowing for real-time adjustments to system parameters based on the conditions within the vapor separation tank 120. The monitoring of these parameters may be crucial for maintaining optimal separation efficiency.
In some embodiments, the vapor separation tank 120 may include a demister or mesh pad positioned near the vapor outlet. This component may serve to capture any remaining liquid droplets that might otherwise be carried out with the vapor stream. The demister may be designed to provide effective droplet removal while minimizing pressure drop through the tank 120.
The vapor separation tank 120 may be thermally insulated to minimize heat transfer between the tank contents and the ambient environment. This insulation may help maintain consistent temperature conditions within the tank 120, enhancing the efficiency of the separation process and reducing unwanted thermal influences on the system 100.
Access ports or hatches may be included in the vapor separation tank 120 to facilitate inspection, cleaning, and maintenance of the internal components. These access points may be sealed with appropriate gaskets to maintain vacuum integrity during operation. The design of these access features may prioritize ease of maintenance while ensuring reliable sealing when the system 100 is operational.
The vapor separation tank 120 may be equipped with a drain valve at its lowest point to allow for complete drainage during maintenance operations or system shutdown. This valve may be manually operated or may be integrated with the control system 122 for automated operation. The drainage system may be designed to direct removed liquid to appropriate collection points for disposal or recycling.
In some configurations, the vapor separation tank 120 may include multiple chambers or sections to enhance the separation process. These chambers may be arranged in series or parallel, depending on the specific requirements of the system 100. The multi-chamber design may allow for progressive separation of vapor and liquid, improving the overall efficiency of the process.
The vapor separation tank 120 may be mounted on a stable platform or base to ensure proper support and to minimize vibration during operation. In some installations, vibration isolation mounts may be used to reduce noise transmission and prevent stress on the tank 120 and connected components. The mounting system may be designed to accommodate thermal expansion and contraction of the tank 120 during operation.
The size and capacity of the vapor separation tank 120 may be determined based on the expected flow rates and separation requirements of the specific system 100 configuration. Larger systems may require correspondingly larger vapor separation tanks to ensure effective separation under all operating conditions. The dimensions of the tank 120 may be optimized to provide adequate residence time for effective separation while minimizing the overall footprint of the system 100.

I. A Control Unit

The control unit 122 may be programmed to monitor and adjust various operational parameters of the refrigeration system 100. The control unit 122 may receive input from multiple sensors strategically positioned throughout the system 100, measuring parameters such as temperature, pressure, flow rates, vacuum levels, and water levels. Based on these inputs, the control unit 122 may execute algorithms to optimize system performance under varying conditions.
The control unit 122 may include a microprocessor or programmable logic controller (PLC) that processes sensor data and executes control logic. This processing capability may allow the control unit 122 to make real-time adjustments to system components based on changing environmental conditions and cooling demands. The control unit 122 may be equipped with memory storage for recording operational data, which may be used for system analysis, optimization, and predictive maintenance.
A user interface may be integrated with the control unit 122, providing system operators with access to operational status information and control capabilities. This interface may include a touchscreen display, LED indicators, or other visual elements that communicate system status effectively. The interface may be designed to present complex system data in an intuitive format, enabling operators to quickly assess system performance and make informed decisions.
The control unit 122 may be programmed with multiple operational modes to accommodate varying cooling requirements and environmental conditions. These modes may include standard operation, energy-saving mode, maximum cooling capacity mode, and maintenance mode. The control unit 122 may automatically select the appropriate mode based on sensor inputs or may allow manual mode selection through the user interface.
Communication capabilities may be incorporated into the control unit 122, enabling remote monitoring and control of the refrigeration system 100. These capabilities may include wired or wireless network connectivity, allowing system operators to access the control unit 122 from off-site locations. Remote access may facilitate troubleshooting, performance monitoring, and system adjustments without requiring physical presence at the installation site.
The control unit 122 may implement proportional-integral-derivative (PID) control algorithms to maintain stable operation of the refrigeration system 100. These algorithms may enable precise control of parameters such as vacuum level, water flow rate, and condenser temperature. The PID parameters may be automatically tuned by the control unit 122 to adapt to changing system dynamics and maintain optimal performance.
Safety monitoring functions may be integrated into the control unit 122 to protect the refrigeration system 100 from damage due to abnormal operating conditions. These functions may include high-pressure protection, low-water-level protection, and over-temperature protection. If unsafe conditions are detected, the control unit 122 may automatically initiate protective measures, such as system shutdown or activation of bypass circuits.
The control unit 122 may be programmed to optimize energy efficiency by adjusting component operation based on cooling demand. For example, the control unit 122 may modulate the speed of the fluid pump 106 to provide only the necessary flow for current conditions, reducing energy consumption during periods of lower cooling demand. Similarly, the control unit 122 may adjust the operation of fans or other auxiliary equipment to minimize power usage while maintaining required cooling capacity.
Diagnostic capabilities may be built into the control unit 122 to identify potential issues before they lead to system failures. These capabilities may include trend analysis of operational data, comparison of current performance to expected parameters, and detection of anomalous behavior. When potential issues are identified, the control unit 122 may generate alerts to notify system operators of the need for maintenance or adjustment.
The control unit 122 may be designed with redundant components and fail-safe mechanisms to ensure reliable operation of the refrigeration system 100. These features may include backup power supplies, redundant sensors, and watchdog timers that monitor the control unit's own operation. In the event of a control system failure, the refrigeration system 100 may be configured to enter a safe operational state until the control unit 122 is restored to normal function.
Expansion capabilities may be incorporated into the control unit 122 to accommodate future system enhancements or additional components. These capabilities may include spare input/output connections, modular hardware architecture, and upgradeable software. The expandable design may allow the control unit 122 to adapt to evolving system requirements without requiring complete replacement.
The control unit 122 may be programmed to manage the transition between different operational states of the refrigeration system 100. These transitions may include system startup, shutdown, and changes between cooling modes. The control unit 122 may execute these transitions in a controlled manner to minimize stress on system components and maintain stable operation throughout the process.
Data logging functions may be implemented in the control unit 122 to record operational parameters over time. This logged data may be used for performance analysis, energy consumption monitoring, and compliance documentation. The control unit 122 may be configured to store data locally and/or transmit it to external storage systems for long-term retention and analysis.
The control unit 122 may include integration capabilities for connecting with building management systems (BMS) or other facility control systems. These capabilities may enable coordinated operation of the refrigeration system 100 with other building systems, such as heating, ventilation, and lighting. The integration may be accomplished through standard communication protocols, allowing for seamless interaction between different control systems.
Alarm management functions may be incorporated into the control unit 122 to notify operators of abnormal conditions or system failures. These functions may include visual and audible alarms at the control unit 122 itself, as well as remote notification capabilities through email, text messages, or other communication channels. The alarm system may be configured with multiple priority levels to distinguish between critical issues requiring immediate attention and less urgent conditions.
The control unit 122 may be designed to operate reliably in various environmental conditions, including temperature extremes, humidity, and potential exposure to water or dust. The enclosure housing the control unit 122 may be rated for the appropriate level of environmental protection based on the installation location. Cooling fans or other thermal management features may be included to maintain appropriate operating temperatures for electronic components within the control unit 122.
The control system 122 may optionally be enhanced with advanced algorithms for predictive maintenance and performance optimization. These algorithms may analyze operational data to identify patterns and potential issues before they affect system performance. In some embodiments, the control system 122 may incorporate machine learning capabilities to continuously improve its operational parameters based on historical performance data.
In some embodiments, the control system 122 may be enhanced with integration capabilities for building management systems (BMS) or industrial control systems. This integration may allow for centralized monitoring and control of the refrigeration system alongside other building or facility systems, enhancing overall operational efficiency.
The control system 122 may be configured with remote monitoring and control capabilities that enable off-site management and troubleshooting. These capabilities may include secure network connectivity, cloud-based data storage, and remote access to control functions, allowing for efficient system management from any location.

Alternative Embodiments

The system 100 may be adapted to interface with various types of existing refrigeration infrastructure beyond CO2 systems. Configurations compatible with ammonia or synthetic refrigerants in direct vaporization or cascade arrangements may be implemented, expanding the versatility of the water vapor refrigeration system. These adaptations may include specialized heat exchangers and control systems designed to optimize performance with specific refrigerants.
Alternative embodiments may include a heat recovery system that captures and repurposes the heat rejected by the condenser 118. This recovered heat may be utilized for space heating, domestic hot water, or process heating applications, enhancing the overall energy efficiency of the facility where the system is installed.
The system 100 may optionally be configured with a variable-capacity design that allows for efficient operation across a wide range of cooling loads. This flexibility may be achieved through the use of variable frequency drives for pumps, modulating valves for flow control, and adaptive control algorithms that adjust system parameters based on current cooling demands.
In some embodiments, the system 100 may optionally include a bypass system that allows for selective isolation of components during maintenance operations without requiring complete system shutdown. This feature may enhance system reliability by minimizing downtime during routine maintenance or component replacement.
Alternative embodiments may incorporate a thermal energy storage system that allows the refrigeration system 100 to operate during off-peak hours and store cooling capacity for use during peak demand periods. This approach may reduce operating costs by taking advantage of lower electricity rates during off-peak hours and may enhance grid stability by reducing peak demand.
Some system embodiments may include specialized configurations for specific applications such as data center cooling, food processing, pharmaceutical manufacturing, or industrial process cooling. These specialized configurations may include custom heat exchangers, control algorithms, and component arrangements optimized for the unique requirements of each application.
The system 100 may, in some embodiments, be adapted for use in mobile applications, such as refrigerated transport or temporary cooling installations. These mobile configurations may include compact designs, enhanced vibration isolation, and rapid deployment features that enable effective cooling in non-permanent installations.
In some embodiments, the system 100 may incorporate renewable energy sources such as solar or wind power to drive the fluid pump and auxiliary components. This integration may further enhance the environmental sustainability of the refrigeration system by reducing reliance on grid electricity.
Alternative embodiments may include a hybrid configuration that combines the vapor refrigeration system 100 with conventional cooling technologies. This hybrid approach may provide redundancy and optimize or otherwise improve system performance across varying operational conditions by leveraging the strengths of each cooling method.
The system 100 may optionally be configured with enhanced safety features in certain embodiments, including automatic shutdown mechanisms, leak detection systems, and pressure relief devices. These safety features may protect both the system components and facility personnel in the event of abnormal operating conditions.
In some embodiments, the vapor refrigeration system 100 may be scaled for residential applications, providing efficient and environmentally friendly cooling for homes. These residential configurations may include compact designs, reduced noise operation, and simplified controls suitable for homeowner operation.
The system 100 may be adapted for integration with thermal storage systems in certain embodiments, allowing for load shifting and peak demand reduction. This integration may enhance the economic benefits of the vapor refrigeration system by optimizing operation based on time-of-use electricity rates and demand charges.
In some embodiments, the vapor refrigeration system 100 may be configured for heat pump operation, providing both heating and cooling capabilities. This dual-mode operation may enhance the versatility of the system and improve its year-round utility in applications where both heating and cooling are required.
Alternative embodiments may incorporate advanced control strategies such as model predictive control or adaptive control algorithms. These strategies may optimize system performance based on anticipated cooling loads, ambient conditions, and operational constraints, further enhancing energy efficiency and reliability.
In some embodiments, the vapor refrigeration system 100 may incorporate phase change materials (PCMs) to enhance thermal stability and efficiency. These materials may absorb or release heat at specific temperature thresholds, providing additional thermal inertia and stabilizing system operation during load fluctuations.
The system 100 may be adapted for use in conjunction with waste heat recovery applications in certain embodiments. The heat rejected by the condenser 118 may be captured and utilized for processes such as desalination, drying, or preheating, enhancing overall energy efficiency and resource utilization.
In some embodiments, the vapor refrigeration system 100 may incorporate advanced automation features such as self-optimization, automatic fault detection and diagnosis, and predictive maintenance scheduling. These features may enhance system reliability and efficiency by proactively addressing potential issues and continuously optimizing operational parameters.
Alternative embodiments may optionally include specialized configurations for off-grid or remote applications where reliable power supply is limited. These configurations may incorporate energy storage systems, low-power components, and efficient operation modes that minimize electricity consumption while maintaining effective cooling performance.
The system 100 may optionally be configured with enhanced noise reduction features in certain embodiments, including vibration isolation mounts, acoustic enclosures, and low-noise pump designs. These features may reduce the acoustic impact of the refrigeration system, making it suitable for noise-sensitive environments such as offices, hospitals, or residential areas.
In some embodiments, the vapor refrigeration system 100 may incorporate advanced fluid treatment technologies to maintain optimal quality for the fluid therein and prevent scale formation or biological growth within the system. These technologies may include filtration, chemical treatment, or UV sterilization to ensure reliable long-term operation without performance degradation due to fluid quality issues.

III. Platform Operation

Embodiments of the present disclosure provide a hardware and/or software platform operative by a set of methods and computer-readable media comprising instructions configured to operate the aforementioned modules and computing elements in accordance with the methods. The following depicts an example of at least one method of a plurality of methods that may be performed by at least one of the aforementioned modules. Various hardware components may be used at the various stages of operations disclosed with reference to each module.
For example, although methods may be described as being performed by a single computing device, it should be understood that, in some embodiments, different operations may be performed by different networked elements in operative communication with the computing device. For example, at least one computing device (e.g., the control unit 122) may be employed in the performance of some or all of the stages disclosed with regard to the methods. Similarly, an apparatus may be employed in the performance of some or all of the stages of the methods.
Furthermore, although the stages of the following example method are disclosed in a particular order, it should be understood that the order is disclosed for illustrative purposes only. Stages may be combined, separated, reordered, and various intermediary stages may exist. Accordingly, it should be understood that the various stages, in various embodiments, may be performed in arrangements that differ from the ones described below. Moreover, various stages may be added or removed from the method without altering or departing from the fundamental scope of the depicted methods and systems disclosed herein.
Consistent with embodiments of the present disclosure, a method may be performed by at least one of the aforementioned modules. The method may be embodied as, for example, but not limited to, computer instructions, which, when executed, perform the method. A method consistent with an embodiment of the disclosure for operating the vapor refrigeration system 100 may be implemented using a computing device (e.g., the control unit 122) or any other component associated with system 100 as described herein.
The vapor refrigeration system 100 operates through two primary cycles that work synergistically to provide efficient cooling without the need for traditional mechanical compression. These cycles may be referred to as the Hydrovaporization Refrigeration Cycle (Cycle 1) and the Auto-Impelled Deep Vacuum Generation Cycle (Cycle 2).

Hydrovaporization Refrigeration Cycle

The Hydrovaporization Refrigeration Cycle (Cycle 1) begins with fluid (e.g., liquid water) in the fluid tank 102, which serves as a “hydrovapor” refrigerant holding tank. The fluid in this tank 102 may be at ambient temperature and pressure. A solenoid valve in a pressure line controls the flow of refrigerant fluid from the fluid tank 102 into the evaporator (e.g., vacuum chamber 112, heat exchanger 116), filling it as needed based on cooling demand signals from the control unit 122.
Fluid from the pressure line enters a needle valve, which may atomize the liquid-phase fluid into fine particles, mechanically initiating the vaporization process. As the fluid passes through the needle valve, the fluid experiences a significant pressure drop that causes partial vaporization. This fluid vapor then enters the heat exchanger 116. As a non-limiting example, when using water as the refrigerant fluid, the heat exchanger may be maintained at approximately 1000 microns, corresponding to a temperature of about 25° F.
Under these vacuum conditions, the fluid boils at a much lower temperature than it would at atmospheric pressure. This low-temperature boiling point provides the necessary heat absorption capacity. For example, when water is the refrigerant, the reduced boiling point provides for heat absorption of approximately 970 BTU/lb, making water an effective refrigerant.
The boiling fluid liquid/vapor mixture enters the heat exchanger 116, where it comes into thermal contact with the medium to be cooled. In typical applications, warm incoming air at approximately 45° F. may pass over the heat exchanger and exit at approximately 35° F., representing a 10° F. temperature differential. Experimental results have demonstrated temperature differentials of up to 12° F., exceeding industry standards for similar cooling capacities.
The heat exchanger 116 operates under the same vacuum conditions as the surrounding lines, maintaining consistent conditions for the refrigeration process. As the fluid absorbs heat from the medium to be cooled, it fully vaporizes and exits the heat exchanger 116 as fluid vapor. For example, water may exit the heat exchanger as water vapor at approximately 35° F. and 1000 microns pressure.
This vapor then enters the vacuum chamber 112, where it is drawn into an evaporator eductor 108 through its vacuum line. The eductor 108 uses the motive fluid flow from the evaporator pump 106 to create the suction necessary to maintain the vacuum conditions in the vacuum chamber 112. A check valve may be installed in this flow path to ensure that water flows only in the intended direction.
The vapor mixes with the motive fluid in the eductor 108 and returns to the water tank 102, completing the Hydrovaporization Refrigeration Cycle. The heat absorbed during this cycle is carried by the vapor and transferred to the fluid in the tank 102, where it may be subsequently removed through the condenser cycle.

Auto-Impelled Deep Vacuum Generation Cycle

The Auto-Impelled Deep Vacuum Generation Cycle (Cycle 2) operates concurrently with the Hydrovaporization Refrigeration Cycle (Cycle 1) to maintain the vacuum conditions necessary for efficient refrigeration. This cycle begins with liquid-phase fluid in the water tank 102 at ambient temperature and pressure.
The fluid is drawn by the evaporator pump 106 from the fluid tank 102 and circulated through the evaporator eductor 108 at high pressure and flow rate, typically around 100 psi and 100 gpm. The evaporator pump 106 may operate at, as a non-limiting example, approximately 11 amps, representing a significant energy efficiency advantage compared to traditional compressor-based systems.
The evaporator eductor 108 creates a deep vacuum in the vacuum chamber and connected evaporator 112 through the venturi effect. As high-pressure fluid from the pump 106 passes through the narrowed section of the eductor 108, the velocity of the fluid increases while the pressure decreases, creating a low-pressure zone that draws in vapor from the heat exchanger 116.
In Cycle 2, no fluid need be present in the vacuum chamber 112 in any form other than vapor being drawn from the heat exchanger 116. The fluid passing through the eductor 108 serves as the motive fluid that creates and maintains the vacuum conditions necessary for the refrigeration process.
After passing through the evaporator eductor 108, the fluid may enter a condenser 118, For example, water may enter the condenser at approximately 110° F. and ambient (atmospheric) pressure. In some configurations, this flow may instead be directed into a dual-circuit condenser, forming part of a self-subcooling loop in the condenser cycle. The fluid then passes through the condenser and into a gravity drain, returning to the fluid tank 102. Continuing with the example above, water that enters the condenser at approximately 110° F. may exit the condenser at approximately 100° F. and ambient pressure.
The Auto-Impelled Deep Vacuum Generation Cycle continuously maintains the vacuum conditions necessary for the Hydrovaporization Refrigeration Cycle to operate efficiently. The control unit 122 may adjust the operation of the evaporator pump 106 based on sensor feedback to maintain optimal vacuum levels under varying cooling load conditions.

Condenser Cycle

The condenser cycle represents another aspect of operation of the water vapor refrigeration system 100. This cycle is responsible for removing the heat absorbed during the Hydrovaporization Refrigeration Cycle and rejecting it to the external environment.
The condenser cycle begins with liquid-phase fluid in the tank 102 at ambient temperature and pressure. This fluid is drawn by the condenser pump 106 and circulated to the condenser eductor 108. The condenser eductor 108 creates suction that draws vapor from the top of the fluid tank 102 through a vapor line.
The vapor drawn from the top of the tank 102 represents the heat that has been absorbed during the Hydrovaporization Refrigeration Cycle. Drawing this vapor from the tank 102 has the additional benefit of subcooling the liquid fluid remaining in the tank, enhancing the overall efficiency of the system.
The vapor travels through the condenser 118, where it releases heat to the external environment or a secondary cooling medium. As the vapor cools, it condenses back to liquid form. This condensed liquid, along with the motive fluid from the condenser eductor 108, returns to the fluid tank 102, completing the condenser cycle.
In some configurations, the condenser 116 may incorporate a dual-circuit design, with one circuit dedicated to condensing the fluid vapor and the other used for subcooling the condensed fluid before it returns to the water tank 102. This approach may enhance the efficiency of the heat rejection process and improve the overall performance of the system.
The condenser cycle operates continuously alongside the other cycles, ensuring that heat is efficiently removed from the system. The control unit 122 may adjust the operation of the condenser pump 107 and associated components based on sensor feedback to maintain optimal condensing conditions under varying heat loads and ambient temperatures.

System Integration and Control

The vapor refrigeration system 100 integrates these cycles through careful design and sophisticated control mechanisms. The control unit 122 continuously monitors various parameters throughout the system, including temperatures, pressures, flow rates, and fluid levels. Based on this information, the control unit 122 adjusts the operation of pumps, valves, and other components to maintain optimal performance under varying conditions.
For example, if the cooling load increases, the control unit 122 may increase the flow rate of the evaporator pump 106 to enhance the vacuum effect and increase the refrigeration capacity. Similarly, if ambient temperatures rise, the control unit 122 may adjust the operation of the condenser fan to ensure efficient heat rejection.
The system may also include various safety features, such as low-fluid-level protection, over-temperature protection, and excessive pressure protection. These features help prevent damage to the system components and ensure safe operation under all conditions.
The integration of these cycles creates a highly efficient refrigeration system that leverages the exceptional thermal properties of fluid, particularly its high latent heat of vaporization, to provide effective cooling with minimal energy input. By operating under vacuum conditions rather than high pressure, the system eliminates the need for traditional compressors and their associated energy consumption and maintenance requirements.

IV. Example Embodiment

The vapor refrigeration system 1000 as shown in FIG. 4 comprises several interconnected components that work together to provide efficient cooling through the use of water as both the motive fluid and refrigerant. While the described system 1000 uses water, it should be understood that other fluids may be substituted with departing from the scope of this invention. The system 1000 operates on principles that differ significantly from conventional refrigeration systems, particularly in its utilization of water's high latent heat of vaporization (approximately 970 BTU/lb) and operation under vacuum conditions rather than high pressure.
The water tank 1010 serves as the central reservoir for the system 1000, storing the supply of water that functions as both the motive fluid and the refrigerant. The water tank 1010 may include a level monitoring system electronically connected to a control unit, enabling automated water level management and system protection against low water conditions that could potentially damage the water pumps.
The system 1000 incorporates two primary water pumps 1020: the evaporator pump 1020 a and the condenser pump 1020 b. Both pumps 1020 are fluidly coupled to the water tank 1010 and are configured to circulate water throughout different circuits of the system.
The evaporator pump 1020 a is connected to a first side of the water tank 1010 and serves to circulate water to the evaporator eductor 1030 a. This pump 1020 a may be designed as a centrifugal pump capable of continuous operation with minimal maintenance requirements. The evaporator pump 1020 a may feature variable flow rate capabilities, allowing for adjustment based on cooling demands. This variability may enhance efficiency of the system 1000 by providing only the necessary flow for current operating conditions.
The evaporator pump 1020 a may operate at pressures ranging from about 75 to about 135 psi and flow rates of about 75 to about 135 gpm, depending on system requirements. The pump 1020 a may include multiple pumping stages to achieve optimal (or nearly optimal) pressure for eductor operation.
The condenser pump 1020 b may be connected to another side of the water tank 1010. The condenser pump 1020 b may circulate water to the condenser eductor 1030 b. The condenser pump 1020 b may share many design characteristics with the evaporator pump 1020 a, including materials of construction and variable flow rate capabilities. The condenser pump 1020 b may maintain appropriate pressure for condenser operation and circulate water through the condenser circuit of the system.
Both pumps 1020 may be equipped with mechanical seal systems to prevent water leakage around the pump shafts. These seal systems may be designed for long-term operation without requiring frequent maintenance or replacement. In some configurations, the pumps may incorporate double mechanical seals with barrier fluid for enhanced reliability in continuous operation.
The inlet of each water pump 1020 may be positioned to ensure adequate submersion in the water tank 1010, preventing air entrainment that could lead to cavitation and reduced pumping efficiency. The pumps 1020 may include strainers or filters at their inlets to prevent debris from entering and potentially damaging the pump impellers or other components.
The discharge side of each water pump may be equipped with check valves to prevent backflow when the pumps are not operating. These check valves may help maintain system pressure and prevent water from flowing back into the water tank 1010 when the system is in standby mode.
The system 1000 utilizes two eductors 1030: the evaporator eductor 1030 a and the condenser eductor 1030 b. These eductors 1030 are specialized fluid jet devices that create suction through the venturi effect, playing a crucial role in the operation of the water vapor refrigeration system.
The evaporator eductor 1030 a is positioned in fluid communication with the evaporator pump 1020 a. The evaporator pump 1020 a may provide motive water to the evaporator eductor 1030 a. The eductor 1030 a creates a vacuum by utilizing the flow of water from the pump 1020 a through a specially-designed nozzle. This nozzle may be specifically engineered to maximize pressure reduction, achieving the desired vacuum level for operation of the refrigeration system 1000. The vacuum created by the eductor 1030 a enables water to boil at lower temperatures, facilitating the refrigeration process without traditional compression methods.
The evaporator eductor 1030 a employs the venturi effect to create and maintain vacuum conditions. As water flows through the narrowed section of the nozzle, the velocity of the water increases while the pressure decreases, creating a low-pressure zone that draws in vapor from an evaporator. This vacuum generation mechanism operates according to Bernoulli's principle, wherein the increased kinetic energy of the water flowing through the constricted section results in a corresponding decrease in pressure.
The vacuum created by the eductor 1030 a may be maintained at a level sufficient to lower the boiling point of water to approximately 25° F., enabling efficient heat absorption from the refrigerant. This low-pressure environment allows water to change phase from liquid to vapor at temperatures well below the standard boiling point, thereby enhancing the capacity of the water to absorb heat from the refrigerant.
The condenser eductor 1030 b is positioned in fluid communication with the condenser pump 1020 b. This eductor 1030 b creates suction to draw vapor from the top of the water tank 1010 through a vapor line.
Both eductors 1030 may be constructed from materials resistant to corrosion and suitable for continuous operation with water as both the motive fluid and refrigerant. These materials may include stainless steel, high-grade polymers, or other corrosion-resistant alloys that can withstand the operating conditions of the system 100.
The nozzles of the eductors 1030 may feature precision-engineered profiles designed to optimize pressure reduction while minimizing energy losses. The geometry of the nozzles may be specifically tailored to achieve the desired vacuum levels with the available water pressure and flow rate from the respective pumps.
The system 1000 includes a pressure line connected to the evaporator pump line. This pressure line delivers controlled amounts of refrigerant to the evaporator 1040. The pressure line may include a solenoid valve for controlling refrigerant flow based on cooling demands. This valve may be electronically controlled (e.g., by a control unit), allowing for automated adjustment of refrigerant flow in response to changing cooling requirements.
A needle valve is positioned downstream of the solenoid valve in the pressure line. This needle valve helps vaporize the liquid water through pressure reduction as it enters the evaporator 1040. The pressure drop across the needle valve causes partial vaporization of the water, initiating the refrigeration process. The needle valve may be adjustable, allowing for fine-tuning of the refrigerant flow and vaporization process based on specific cooling requirements.
The configuration of these valves may be optimized to deliver controlled amounts of refrigerant to the evaporator 1040 while maintaining the vacuum conditions necessary for efficient operation of the system 1000. The solenoid valve may include features such as manual override capabilities for service and maintenance operations, while the needle valve may incorporate precise adjustment mechanisms for optimal system tuning.
The evaporator 1040 is a heat exchanger where liquid refrigerant absorbs heat and vaporizes. Connected to the needle valve inlet and the evaporator eductor 103 a outlet, the evaporator 1040 provides the cooling effect to the intended application. The evaporator 1040 may be designed for efficient heat transfer and phase change, with configurations optimized for the specific cooling application.
The evaporator 1040 may be constructed from materials with high thermal conductivity, such as (but not limited to) copper, aluminum, stainless steel, and/or the like, to maximize heat transfer efficiency. The design may incorporate enhanced surface features such as fins, corrugations, or microchannels to increase the effective heat transfer area, improving overall thermal performance.
In the evaporator 1040, water entering through the needle valve undergoes evaporation under vacuum conditions. This evaporation process absorbs heat from the medium to be cooled, providing the refrigeration effect. The vacuum conditions within the evaporator 1040 are maintained by the evaporator eductor 1030 a, helping to ensure that water boils at the desired low temperature.
The evaporator 1040 may include temperature sensors at strategic locations to monitor performance and provide data to the control unit. These sensors may enable real- time adjustments to system parameters to maintain optimal heat transfer conditions under varying loads and ambient conditions.
A vapor line is connected to the top of the water tank 1010 and draws vapor from the headspace of the tank. This line routes vapor to the condenser 1050, helping subcool the water in the tank 1010 by removing warm vapor. The vapor line may be sized appropriately to accommodate the expected vapor flow rates under various operating conditions.
The vapor line may be constructed from materials suitable for operation under vacuum conditions and compatible with water vapor as the working fluid. These materials may include, as non-limiting examples, stainless steel, certain grades of aluminum, high-performance polymers, and/or other materials that can withstand the operational stresses while resisting corrosion or degradation.
Insulation may be applied to the vapor line to minimize unwanted heat transfer between the vapor and the ambient environment. This insulation helps maintain the efficiency of the refrigeration cycle by preserving the thermal energy contained within the vapor for proper heat rejection at the condenser 1050.
The condenser 1050 is a heat exchanger where vapor releases heat and condenses to liquid. Connected between the vapor line and condenser eductor 1030 b, the condenser 1050 rejects heat to the environment and/or a secondary cooling medium and returns condensed liquid to the condenser eductor 1030 b.
The condenser 105 may include one or more (e.g., multiple) condensing coils designed to maximize surface area contact with the vaporized refrigerant. These coils may be constructed from materials with high thermal conductivity, such as copper, aluminum, and/or the like, to enhance heat rejection efficiency. The arrangement of these coils may help to ensure efficient heat transfer while minimizing pressure drop.
A fan assembly may be incorporated within the condenser 1050 to facilitate the dissipation of heat from the condensing coils to the external environment. The fan speed may be variable and controlled by the control unit based on condensing requirements and ambient conditions. This variable speed capability may allow for energy-efficient operation across a range of thermal loads.
The condenser 1050 may also include fins attached to the condensing coils to increase the effective surface area for heat exchange. These fins may be designed with specific geometries to optimize airflow and heat transfer characteristics. The spacing and configuration of these fins may be tailored to balance heat transfer efficiency with air pressure drop considerations.
Temperature sensors may be strategically placed within the condenser 1050 to monitor the temperature of the refrigerant within the condensing coils. These sensors may provide data to the control unit, allowing for precise control of the condensing process. The control unit may adjust fan speed or other parameters based on these temperature readings to maintain optimal condensing conditions.
The control unit 1060 may be programmed to monitor and adjust various operational parameters of the refrigeration system 1000. The control unit 1060 may receive input from multiple sensors strategically positioned throughout the system 1000, measuring parameters such as temperature, pressure, flow rates, vacuum levels, and water levels. Based on these inputs, the control unit 1060 may execute algorithms to optimize or otherwise improve system performance under varying conditions.
The control unit 1060 may include a microprocessor or programmable logic controller (PLC) that processes sensor data and executes control logic. This processing capability may allow the control unit 1060 to make real-time adjustments to system components based on changing environmental conditions and cooling demands. The control unit 1060 may be equipped with memory storage for recording operational data, which may be used for system analysis, optimization, and predictive maintenance.
A user interface may be integrated with the control unit 1060, providing system operators with access to operational status information and control capabilities. This interface may include a touchscreen display, LED indicators, and/or other visual elements that communicate system status effectively. The interface may be designed to present complex system data in an intuitive format, enabling operators to quickly assess system performance and make informed decisions.
The control unit 1060 may be programmed with multiple operational modes to accommodate varying cooling requirements and environmental conditions. These modes may include standard operation, energy-saving mode, maximum cooling capacity mode, and maintenance mode. The control unit 1060 may automatically select the appropriate mode based on sensor inputs and/or may allow manual mode selection through the user interface.
Communication capabilities may be incorporated into the control unit 1060, enabling remote monitoring and control of the refrigeration system 1000. These capabilities may include wired or wireless network connectivity, allowing system operators to access the control unit 1060 from off-site locations. Remote access may facilitate troubleshooting, performance monitoring, and system adjustments without requiring physical presence at the installation site.
In operation, the water vapor refrigeration system 1000 operates through two primary cycles that work together to provide efficient cooling. These cycles may be referred to as the evaporator cycle and the condenser cycle.
In the evaporator cycle, liquid water begins in the water tank 1010 at ambient temperature and pressure. The evaporator pump 1020 a circulates this water to the evaporator eductor 1030 a, creating the motive force needed for system operation. A portion of the water is directed through the pressure line to the solenoid valve, which controls the on/off flow of refrigerant into the evaporator 140 based on cooling demands.
The water passes through the needle valve, experiencing a pressure drop that causes partial vaporization. The remaining liquid water enters the evaporator 1040, where it absorbs heat from the medium to be cooled and fully vaporizes under vacuum conditions. This vacuum environment may be maintained at approximately 1000 microns, allowing water to boil at temperatures as low as 25° F.
The water vapor is drawn from the evaporator 1040 into the evaporator eductor 1030 a through its vacuum line. In the eductor 1030 a, the water vapor is mixed with the motive water flow and returned to the water tank 1010. A check valve may be positioned in this return line to ensure that water flows only in the intended direction.
In the condenser cycle, liquid water from the water tank 1010 is drawn by the condenser pump 1020 b and circulated through the condenser eductor 1030 b. The condenser eductor 1030 b creates suction that draws vapor from the top of the water tank 1010 through the vapor line. This vapor represents the heat that has been absorbed in the evaporator cycle.
The vapor travels through the condenser 1050, where it releases heat to the external environment and/or a secondary cooling medium. As heat is rejected, the vapor condenses back to liquid form. This condensed liquid, along with the motive water from the condenser eductor 1030 b, returns to the water tank 1010, completing the cycle.
The removal of vapor from the top of the water tank 1010 through the vapor line has the additional benefit of subcooling the water in the tank, enhancing the efficiency of the overall system. The control unit 1060 continuously monitors and adjusts various parameters such as pump speeds, valve positions, and fan operation to maintain optimal system performance under varying cooling loads and ambient conditions.
The water vapor refrigeration system 1000 may be configured to operate as a high stage in a cascade refrigeration system with a secondary refrigerant circuit. This configuration may be particularly advantageous when used with CO2 as the low-stage refrigerant, as the water vapor system may maintain subcritical CO2 conditions regardless of ambient temperatures.
In this cascade arrangement, the heat exchanger in the water vapor system may be designed to transfer heat from the CO2 refrigerant to the evaporated water. The cooling effect provided by the water vapor system may maintain the CO2 temperature below its critical point (approximately 88° F.), ensuring that the CO2 remains in a subcritical state regardless of ambient conditions. This subcritical operation of CO2 may significantly improve the efficiency of the overall refrigeration system compared to transcritical CO2 operation, which is less efficient.
The cascade configuration may allow the system to achieve lower temperatures than would be possible with a single-stage water vapor system, making it suitable for applications requiring deep refrigeration. The water vapor system serves as the high stage, rejecting heat to the environment, while the CO2 system serves as the low stage, providing the desired low-temperature refrigeration effect.
The water vapor refrigeration system 100 may achieve cooling capacities of 5 tons (approximately 64,640 BTU/hr) or more, depending on the specific configuration and component sizing. The system may operate with a coefficient of performance (COP) of approximately 11.76, significantly higher than the typical COP of 2.5-4.0 achieved by conventional refrigeration systems.
This exceptional efficiency is made possible by several factors, including the elimination of the traditional compressor (which typically accounts for approximately 25% of the total energy consumption in conventional refrigeration systems), the high latent heat of vaporization of water (approximately 970 BTU/lb), and the efficient heat transfer characteristics of the system design.
The system may achieve temperature reductions of up to 35° F. in 60 minutes, with experimental results demonstrating temperature differentials of up to 12° F. across the evaporator, exceeding industry standards for similar cooling capacities. These performance characteristics make the water vapor refrigeration system 100 suitable for a wide range of applications, from commercial and industrial refrigeration to data center cooling and building climate control.
The water vapor refrigeration system 100 offers numerous advantages over conventional cooling technologies, making it suitable for a wide range of applications where efficient, environmentally friendly cooling is required.
One advantage of the water vapor refrigeration system 100 is its environmental sustainability. The system uses water, which is non-toxic and has zero global warming potential, as both the motive fluid and refrigerant. This eliminates the need for synthetic refrigerants with significant global warming potential, such as hydrofluorocarbons (HFCs), which are being phased out globally due to their environmental impact.
The system's high efficiency also contributes to its environmental sustainability by reducing energy consumption compared to conventional refrigeration systems. This reduction in energy use translates to lower greenhouse gas emissions associated with electricity generation, further enhancing the system's environmental benefits.
The water vapor refrigeration system 100 operates at sub-atmospheric pressures rather than the high pressures (often exceeding 400 PSI) typical in conventional refrigeration systems. This low-pressure operation reduces the risk of refrigerant leaks and eliminates the safety concerns associated with high-pressure systems. Additionally, the use of water as the refrigerant eliminates the toxicity concerns associated with some alternative refrigerants such as ammonia.
The elimination of high-pressure components also reduces the structural requirements for the system, potentially allowing for lighter, more cost-effective components compared to conventional high-pressure refrigeration systems. This may lead to reduced manufacturing costs and easier installation and maintenance.
The water vapor refrigeration system 100 eliminates many of the complex components found in conventional refrigeration systems, such as compressors and oil management systems. This simplification reduces the maintenance requirements and potential failure points in the system, leading to increased reliability and reduced operational costs over the system's lifespan.
The elimination of oil management systems is particularly significant, as oil-related issues are a common source of problems in conventional refrigeration systems. The water-based operation of the system 100 eliminates these concerns entirely, further reducing maintenance requirements and enhancing reliability.
The water vapor refrigeration system 100 may achieve a coefficient of performance (COP) of approximately 11.76, significantly higher than the typical COP of 2.5-4.0 achieved by conventional refrigeration systems. This exceptional efficiency translates to substantial energy savings, with potential reductions in cooling energy consumption of 50-90% compared to conventional systems.
The high efficiency of the system 100 is attributed to several factors, including the elimination of the traditional compressor (which typically accounts for approximately 25% of the total energy consumption in conventional refrigeration systems), the high latent heat of vaporization of water (approximately 970 BTU/lb), and the efficient heat transfer characteristics of the system design.
When configured as the high stage in a cascade refrigeration system with CO2 as the low-stage refrigerant, the water vapor system 100 offers additional benefits. The system may maintain CO2 in a subcritical state regardless of ambient temperatures, significantly improving the efficiency of CO2 refrigeration systems, particularly in warm climates where conventional CO2 systems often operate in less efficient transcritical modes.
This capability may be particularly valuable in regions within the “CO2 equator,” where high ambient temperatures have traditionally limited the efficiency and adoption of CO2 refrigeration systems. By enabling efficient subcritical CO2 operation in these regions, the water vapor refrigeration system 100 may expand the geographical range where environmentally friendly CO2 refrigeration is practical and cost-effective.

Claims

The following is claimed

1. A refrigeration system, comprising:

a tank for storing a fluid supply;

a fluid pump fluidly coupled to the tank, configured to circulate water from the water tank;

an eductor in fluid communication with the fluid pump, the eductor being operative to create a vacuum by utilizing a flow of fluid from the fluid pump;

a vacuum chamber fluidly connected to the eductor, wherein the vacuum chamber is structured to facilitate evaporation of the fluid under vacuum conditions to absorb heat from a refrigerant;

a heat exchanger in thermal communication with the vacuum chamber, the heat exchanger being configured to transfer heat from the refrigerant to the evaporated fluid; and

a condenser fluidly connected to the tank, the condenser being configured to condense the evaporated fluid and to discharge the heat absorbed from the refrigerant.

2. The refrigeration system of claim 1, wherein the fluid pump is characterized by a variable flow rate to control a volume of fluid supplied to the eductor based on operational demands of the system.

3. The refrigeration system of claim 1, wherein the fluid is one of the following:

water,

ammonia,

carbon dioxide, or

a synthetic refrigerant.

4. The refrigeration system of claim 1, wherein the vacuum chamber includes a float mechanism to maintain a predetermined level of the fluid within the chamber, ensuring consistent evaporation.

5. The refrigeration system of claim 1, wherein the heat exchanger is specifically configured for use with a CO2 refrigerant in a subcritical state, facilitated by a cooling effect of the evaporated fluid.

6. The refrigeration system of claim 1, further comprising a control unit programmed to monitor and adjust pressure within the vacuum chamber, flow rate of the fluid pump, and temperature of the condenser.

7. The refrigeration system of claim 1, further comprising a vapor separation tank positioned between the eductor and the tank, the vapor separation tank being configured to separate entrained liquid from vapor.

8. The refrigeration system of claim 1, wherein the system is configured to operate as a high stage in a cascade refrigeration system with a secondary refrigerant circuit.

9. The refrigeration system of claim 1, further comprising a liquid ring vacuum pump or other style of pump or mechanism, as an alternative mechanism for maintaining vacuum within the vacuum chamber.

10. The refrigeration system of claim 1, wherein the heat exchanger is adapted to facilitate heat exchange between the evaporated water and a secondary refrigerant in a cascade refrigeration cycle.

11. The refrigeration system of claim 1, wherein the system maintains similar vacuum levels throughout.

12. The refrigeration system of claim 1, further comprising a bypass valve system for selectively isolating components of the system during maintenance operations.

13. The refrigeration system of claim 1, wherein the system is configurable to operate in multiple modes to accommodate varying environmental conditions and cooling load requirements.

14. A refrigeration system, comprising:

a water tank configured to store water;

a first water pump fluidly coupled to the water tank;

a first eductor fluidly connected to the first water pump, the first eductor configured to create a vacuum using water from the first water pump;

an evaporator fluidly connected to the first eductor, the evaporator configured to facilitate water evaporation under vacuum conditions;

a second water pump fluidly coupled to the water tank;

a second eductor fluidly connected to the second water pump; and

a condenser fluidly connected to the second eductor and to the water tank, the condenser configured to receive water vapor from the water tank and condense the water vapor.

15. The refrigeration system of claim 14, further comprising:

a pressure line fluidly connecting the first water pump to the evaporator;

a solenoid valve positioned in the pressure line; and

a needle valve positioned in the pressure line downstream of the solenoid valve.

16. The refrigeration system of claim 14, further comprising a vapor line fluidly connecting a top portion of the water tank to the condenser.

17. The refrigeration system of claim 14, wherein:

the second water pump is configured to provide motive water to the second eductor;

the second eductor is configured to receive condensed water from the condenser and mix the condensed water with the motive water; and

the second eductor is configured to return the mixed condensed water and motive water to the water tank.

18. The refrigeration system of claim 14, wherein the evaporator is configured to cool incoming air by evaporating water under vacuum conditions.

19. The refrigeration system of claim 14, wherein the condenser is configured to subcool water in the water tank by drawing vapor from a top portion of the water tank.

20. The refrigeration system of claim 14, wherein the first eductor and the second eductor are configured to operate based on a venturi effect to create vacuum conditions.