CN116858003A - Condenser and waste heat recovery system thereof - Google Patents

Abstract

The application provides a condenser, which comprises a spray box body and a water storage tank body, wherein the top parts of the spray box body and the water storage tank body are respectively provided with an inlet, the bottom parts of the spray box body and the water storage tank body are respectively provided with an outlet, a heat pipe is connected with the spray box body and the water storage tank body, the heat pipe in the spray box body is obliquely inserted into the water storage tank body upwards at a certain angle, and when in spraying, gaseous hot fluid is injected into a spray header from a pipe orifice at the top and is diffused into the box body, becomes liquid after exchanging heat with the heat pipe, flows out from the pipe orifice at the bottom part and enters the next two-phase pump driving circulation; cold water in the water storage tank body is injected from a top pipe orifice, and hot water is discharged from a bottom pipe orifice. The application designs a novel structure condenser, wherein the condensation waste heat is used as a heat source, circulating water is used as a cold source, the heat absorbing end of a heat pipe is welded with annular fins, the high-efficiency condensation heat release can be realized by combining an atomization spraying device, the heat releasing section of the heat pipe is immersed in a heat storage water tank, and the cold water is heated through heat exchange, so that the waste heat recovery is realized.

Description

A condenser and residual heat recovery system

Technical field

The invention relates to a heat pipe technology, in particular to a waste heat recovery loop heat pipe, which belongs to the heat pipe field of F28d15/02.

Background technique

Heat pipe technology is a heat transfer element called a "heat pipe" invented by George Grover of the Los Alamos National Laboratory in the United States in 1963. It makes full use of the principle of heat conduction and phase change media. The rapid heat transfer property of the heat pipe can quickly transfer the heat of the heating object to the outside of the heat source. Its thermal conductivity exceeds that of any known metal.

Heat pipe technology has been widely used in aerospace, military and other industries before. Since it was introduced into the radiator manufacturing industry, people have changed the design ideas of traditional radiators and got rid of the single cooling mode that simply relies on high air volume motors to obtain better heat dissipation effects. The use of heat pipe technology enables the radiator to achieve satisfactory heat exchange effects, opening up a new world in the heat dissipation industry. At present, heat pipes are widely used in various heat exchange equipment, including nuclear power and computer fields, such as waste heat utilization of nuclear power.

Loop heat pipe refers to a closed loop heat pipe. It generally consists of an evaporator, condenser, liquid reservoir, and vapor and liquid pipelines. Its working principle is as follows: applying a thermal load to the evaporator, the fluid evaporates on the outer surface of the evaporator capillary core, and the generated vapor flows out from the vapor channel into the vapor pipeline, and then enters the condenser to be condensed into liquid and subcooled, and the reflux liquid passes through the liquid pipeline. It enters the liquid main channel to replenish the evaporator capillary wick, and so on, and the circulation of the fluid is driven by the capillary pressure generated by the evaporator capillary wick without external power. Since the condensation section and the evaporation section are separated, the loop heat pipe is widely used in the comprehensive application of energy and the recovery of waste heat.

As the demand for server cooling continues to increase, the most common air cooling solution in domestic data centers is difficult to meet standards, and the cost of liquid cooling solutions is extremely high. In view of the above defects, the present invention improves the current loop heat pipe and proposes a new waste heat recovery type pump-driven two-phase loop heat pipe, which is based on mechanical pump-driven two-phase fluid loop technology and waste heat recovery technology. It meets the heat dissipation requirements of servers with high heat flux density and can recycle waste heat. It has the advantages of large heat dissipation, low PUE value, high flexibility, and waste heat recovery.

The present invention also develops a new structural condenser to improve the condensation efficiency.

Contents of the invention

The invention provides a waste heat recovery type pump-driven two-phase loop heat pipe to solve the technical problem of low heat exchange capacity of the heat dissipation loop heat pipe.

In order to achieve the above objects, the technical solutions of the present invention are as follows:

A condenser includes a spray box and a water storage box. The spray box and the water storage box each have an inlet at the top and an outlet at the bottom. A heat pipe connects the spray box and the water storage box. The heat pipe in the shower box is inserted into the water storage box at a certain angle. When spraying, the gaseous hot fluid is injected into the shower head from the top nozzle, diffuses into the box, exchanges heat with the heat pipe, and becomes liquid. flows out and enters the next pump-driven two-phase cycle; cold water in the water storage tank is injected from the top nozzle, and hot water is released from the bottom nozzle.

Preferably, a shower head is provided on the upper part of the shower box, and the spray direction of the shower head is tilted at a certain angle, and the tilt direction is consistent with the tilt direction of the heat pipe.

Preferably, the heat pipes in the spray box are arranged in a fork row to increase the contact area between the large ends of the heat pipes and the sprayed hot fluid.

Preferably, the heat pipe includes a big end and a small end, the big end of the heat pipe is inserted into the spray box, and the small end of the heat pipe is inserted into the water storage box.

Preferably, the large end is provided with thermal fins.

Preferably, the pipe diameter and length of the big end are larger than that of the small end.

A waste heat recovery loop heat pipe system includes a preheater, an evaporator, a condenser, a liquid reservoir, a pump and a regenerator. The preheater, evaporator, condenser and liquid reservoir are connected in sequence through pipelines. The liquid container is connected to the regenerator through a pipeline, a pump is provided on the pipeline between the liquid reservoir and the regenerator, and the regenerator is connected to the preheater through a pipeline.

Compared with the prior art, the present invention has the following advantages:

1) The present invention designs a new structure condenser, in which the waste heat of condensation is used as the heat source and circulating water is used as the cold source. The heat-absorbing end of the heat pipe is welded with annular fins. Combined with the atomizing spray device, high-efficiency condensation heat release can be achieved, and the heat pipe releases heat. The hot section is immersed in the hot water storage tank and heats the cold water through heat exchange to realize waste heat recovery.

2) The present invention proposes a new type of waste heat recovery type pump-driven two-phase loop heat pipe, which is based on mechanical pump-driven two-phase fluid loop technology and phase change heat transfer technology to meet the heat dissipation requirements of high heat flux density and waste heat. Recycling has the advantages of large heat dissipation, low PUE value, wide application, and green emission reduction.

3) Before entering the evaporator, the subcooled fluid of the present invention is preheated through a regenerator and a preheater to reach a saturated state. Because the heat absorption of latent heat of phase change is much greater than that of non-latent heat exchange, this application heats the supercooled fluid to the critical temperature of the latent heat of vaporization, so that it absorbs latent heat immediately after entering the evaporator, achieving rapid absorption of the evaporator. heat, improving the rapid heat absorption efficiency.

4) The present invention designs a new structural evaporator. Its internal manifold arrangement structure and micro-channel design extend the working fluid flow time and heat exchange area, and improve the heat transfer efficiency. By adding a branched tube plate structure and liquid storage The grooves optimize the fluid flow path and reduce flow resistance, which can reduce pump power consumption and ensure uniform distribution of working fluid and efficient heat dissipation.

5) The present invention designs a new structural liquid reservoir, which innovatively adopts a separate structure. The large liquid storage tank is responsible for storing the working fluid, which has a buffering effect on the fluid level fluctuations in the MPTL circuit; the small liquid storage tank is responsible for controlling the pressure. Compared with the traditional single liquid storage device, the control part of the separate liquid storage device has changed greatly. Small, which improves the system sensing sensitivity and control accuracy. A heat exchange spiral tube is added to the small liquid storage tank. Compared with the traditional liquid storage device that is refrigerated through PTC refrigeration plates, the spiral tube passive cooling method can reduce the refrigeration power consumption and can also control the fluid entering the next cycle. Warm up.

6) The present invention designs a regenerator, which adopts a double-circuit cross-counterflow heat exchange scheme and uses brass as the heat transfer medium, which can greatly increase the internal heat of the regenerator while avoiding corrosion of the working fluid ammonia and materials. The heat exchange efficiency between the working fluid and the cold working fluid is achieved, and the heat exchange between the hot fluid flowing out of the evaporator and the cold fluid flowing out of the pump is realized, and the temperature difference is fully utilized to achieve heat exchange and primary preheating in advance.

7) The present invention designs a new type of heat pipe. The microporous capillary core structure filled in it can quickly absorb the heat transfer medium in the heat pipe, making the vaporization heat exchange rate of the phase change working medium inside the heat pipe higher. It is different from the traditional heat pipe. Compared with gravity heat pipes, they have higher thermal conductivity and stronger reliability.

Description of the drawings

Figure 1 is a schematic diagram of the overall structure of the loop heat pipe of the present invention.

Figure 2 is a schematic structural diagram of the bottom plate of the evaporator of the present invention.

Figure 3 is a schematic structural diagram of the evaporator of the present invention.

Figure 4 is a schematic structural diagram of the upper plate of the evaporator of the present invention.

Figure 5 is a schematic structural diagram of the liquid reservoir of the present invention.

Figure 6 is a schematic diagram of the heat pipe structure in the condenser.

Figure 7 is a schematic diagram of the heat pipe structure in the condenser.

Figure 8 is a schematic diagram of the overall structure of the condenser of the present invention.

Figure 9 is a schematic diagram of the heat pipe layout.

Detailed ways

The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

In this article, if there is no special explanation, when formulas are involved, "/" means division, and "×" and "*" mean multiplication.

Figure 1 shows the loop heat pipe system of the present invention. The loop heat pipe system of the present invention is a waste heat recovery type pump-driven two-phase energy-saving system, which is based on mechanical pump-driven two-phase fluid loop technology (Mechanically Pumped Two-phase Loop, MPTL) and waste heat recovery technology to meet the needs of high-end servers. The heat flux density is required for heat dissipation and can recycle waste heat. It has the advantages of large heat dissipation, low PUE value, high flexibility, and waste heat recovery.

As shown in Figure 1, a waste heat recovery loop heat pipe system includes a preheater 1, an evaporator 2, a condenser 3, a liquid reservoir 4, a pump 5 and a regenerator 6. The preheater 1, the evaporator 2 , condenser 3, and liquid reservoir 4 are connected in sequence through pipelines. Liquid reservoir 4 is connected to regenerator 6 through pipelines. A pump 5 is installed on the pipeline between liquid reservoir 4 and regenerator 6. Regenerator 6 Connect to preheater 1 through pipelines. Pump 5 is preferably a mechanical pump.

Referring to Figure 1, when the loop heat pipe system starts to work, the single-phase cold fluid is driven and controlled by the mechanical pump 5. During operation, the subcooled liquid phase fluid (preferably ammonia) first flows into the regenerator 6 driven by the mechanical pump 5 , and the subcooled liquid phase fluid and the two-phase hot fluid flowing out of the evaporator 2 are in the regenerator 5 A heat exchange is performed, and the heat-exchanged single-phase liquid fluid flows into the preheater 1 for secondary heating. At this time, the temperature of the single-phase liquid fluid rises to the saturation temperature, and the liquid fluid does not undergo a phase change at this time.

The fluid that reaches the saturation temperature in the preheater 1 flows into the evaporator 2. After absorbing heat in the evaporator 2, the fluid changes from a liquid single phase to a vapor-liquid two-phase state. The fluid absorbs a large amount of heat due to vaporization, and the dryness increases. The fluid evaporates and absorbs heat in the evaporator 2, and through the circulation flow process in the pipeline, the target heat is absorbed and transported.

Preferably, the evaporator 2 is in direct coupling contact with the heat source to facilitate further heat absorption.

The fluid that absorbs heat in the evaporator 2 enters the regenerator 7, exchanges heat with the supercooled liquid fluid from the liquid reservoir, and then enters the condenser for heat exchange, releases the heat and enters the liquid reservoir, thereby Completed a cycle.

The present invention proposes a new waste heat recovery type pump-driven two-phase flow system, which is based on mechanical pump-driven two-phase fluid circuit technology and waste heat recovery technology to meet the heat dissipation requirements of high heat flux density and can recycle waste heat. It has the advantages of large heat dissipation, low PUE value, high flexibility, and waste heat recovery.

Because the heat absorption time of the fluid in the evaporator is shorter, the heat absorption rate is slower. Before entering the evaporator, the subcooled fluid of the present invention is preheated through a regenerator and a preheater so that it reaches a saturated state. Because the amount of heat absorbed by the latent heat of phase change is much greater than the heat exchange amount of sensible heat, this application heats the supercooled fluid to the critical temperature of the latent heat of vaporization, so that it absorbs latent heat immediately after entering the evaporator, achieving rapid absorption of the evaporator. heat, improving the heat absorption efficiency of the evaporator.

Considering that the preheater consumes a certain amount of electrical energy when heating the cold fluid, the two-phase hot fluid flowing out from the evaporator (because the liquid ammonia may not be completely vaporized in the evaporator, so what flows out from the evaporator is a vapor-liquid two-phase The coexisting fluid) has a large amount of heat, so the team cleverly made the two-phase hot fluid pipe contact with the cold fluid pipe for heat exchange, and used the heat of the hot fluid to heat the cold fluid first, thus reducing the power consumption of the preheater. It also plays the role of condensing hot fluid in advance. This process is called "reheat", and the corresponding device is called "regenerator".

The two-phase fluid coming out of the regenerator 6 enters the condenser 3 for heat exchange. When the condenser 3 is working, the two-phase fluid changes from a vapor-liquid two-phase state to a liquid single-phase state, and the dryness decreases. At the same time, most of the heat released by the condensation of the hot fluid is transferred to the energy storage tank 3-3 by the heat pipe fin array 3-1, and is stored in the circulating water, so that the waste heat can be recycled and effectively reduce waste heat pollution and secondary pollution. Secondary carbon emissions.

The condensed fluid flows into the liquid reservoir 4, and the liquid reservoir 4 regulates the flow and pressure, and maintains a constant pressure in the device. The cold fluid is provided with working fluid circulation driving force by the mechanical pump 5 so as to enter the regenerator 6 for processing. In the next working cycle, the process is repeated to achieve high heat flux density cooling function.

Preferably, part of the fluid from the condenser is directly driven by the pump 5 into the regenerator 6 for the next cycle, and part of it is stored in the liquid reservoir 4 so that it can be driven by the pump to enter the cycle when the circulating fluid is reduced.

As a preferred option, the evaporator adopts a manifold microchannel heat sink structure.

As shown in Figure 2, the evaporator 2 includes a cover plate and a bottom plate. As shown in Figure 3, the bottom plate is provided with a guide plate 2-1, a liquid storage tank 2-2, a vapor-liquid outlet 2-3, and a side slope 2. -4. Micro channel 2-5, liquid inlet 2-6, slope V-shaped groove 2-7 and exhaust channel 2-8. The bottom plate includes an evaporator liquid storage tank 2-2 arranged in the middle of the bottom plate. Micro channels 2-5 are provided on both sides of the liquid storage tank 2-2, and a guide plate 2-1 is provided above the micro channel 2-5. The guide plate plays a role in changing the flow path of the gas-phase working fluid. After the liquid working medium is heated and evaporates, it turns into a gaseous state. The gas-phase working fluid rises when heated. However, due to the blocking effect of the guide plate, the gas-phase working fluid cannot flow from the top layer inside the evaporator. It can only be discharged from the micro-channel under the guide plate. Preferably, the baffle is directly welded to the upper part of the microchannel. One side of the liquid storage tank is connected to the evaporator inlet 2-6, and an outlet 2-3 is provided on the other side opposite to the inlet. The outlet 2-3 is connected to an outflow channel. The outflow channel includes an outer side provided on the upper part of the microchannel and is connected to the evaporator inlet 2-6. The first part 2-4 connected by the microchannel, the second part is arranged at the outlet end of the bottom plate and extends along one end of the outlet, the ends on both sides of the second part are connected with the first part, and the middle part of the second part is connected with the outlet 2 -3 connected.

The position where the microchannel communicates with the first part 2-4 is located at the end of the first part away from the second part. By setting in this way, excessive overflowing liquid is prevented from entering the second part, and excess water in the output soda-water mixture is avoided.

The baffle 2-1 is arranged close to the first part, and a part of the micro-channels not covered by the baffle remains between the first part and the baffle. This part of the micro-channels forms an exhaust channel for steam to be discharged. 2-8.

In the above evaporator structure, the fluid first flows into the liquid storage tank 2-2 in the vertical direction of the microchannel, then splits to both sides, and then flows in the microchannel to merge near the outlet. This flow channel design makes the flow channel cycle in the heat sink more repeatable, and the original long straight microchannel is segmented into short and bent microchannel units. It has the characteristics of small thermal resistance, small inlet and outlet pressure loss, uniform heat exchange, compact structure and suitable for heat dissipation of electronic components.

The second part is not connected to the microchannel and liquid reservoir. The gas flows out from the micro-channel on the other side through the diversion groove and enters the second part. The effect of the disconnection is to prevent the liquid working medium from directly entering the second part and blocking the gas channel, and prevent the liquid working medium from being discharged before it can absorb heat. The liquid After overflowing the microchannel, it accumulates in the first part, and then flows to the outlet 2-3 through the second part. The liquid volume is not very large, and most of it has been vaporized, so the length of the first part does not need to be very long.

The first part is set between the entrance and the exit close to the exit, and the length is 1/3-1/4 of the distance between the entrance and the exit. Setting this distance can ensure that more liquid can fully absorb heat and generate steam as much as possible to avoid a large amount of liquid entering the first part.

Preferably, the first part is an inclined structure, gradually becoming deeper and deeper from the outside to the inside. The second part is the slope V-shaped groove 2-7, which gradually becomes deeper and deeper from both ends to the center, and the lowest point is set at the exit position. Preferably, the bottom wall of the first part slopes downward toward the second part to ensure that liquid can enter the fast second part.

As a preference, the V-groove structure is 145-155°.

The slope-type V-shaped grooves 2-7 in Figure 3 are used to realize automatic diversion of liquid and discharge of residual liquid with maximum efficiency. The V-shaped angle design of about 150° combined with the outlet with a diameter of 7mm can achieve a better liquid discharge rate. Moreover, the outlet is in a tangent relationship with the bottom end of the V-shaped groove 2-7 in Figure 3. The smooth transition reduces the liquid flow resistance to a minimum, ensuring that the residual liquid in the device is removed in time and preventing excessive accumulation of liquid from causing internal blockage. The unique Figure 3 The V-shaped groove 2-7 design facilitates the stable operation of the protection device.

Fluid liquid ammonia flows into the evaporator liquid storage tank 2-2 through the pipeline, and the liquid level rises in the liquid storage tank 22 in Figure 2. When the liquid level rises to a certain height, the fluid liquid ammonia will spread to both sides and flow into Figure 2 In microchannels 2-5 (this is a uniform splitting process, that is, the amount of fluid flowing into each microchannel per unit time is equal, and uniform splitting is conducive to improving the heat absorption efficiency of the evaporator). Due to the microchannel 2 in Figure 2 The bottom of -5 is the heat source. Metal aluminum with good thermal conductivity is selected, which can transfer heat to the liquid heat-absorbing fluid through the evaporator in time. At this time, the fluid begins to absorb heat. When the fluid temperature reaches the boiling point, it begins to vaporize, and the fluid is The liquid state is converted into a gaseous state. The gaseous fluid rises when heated, and the gas transfer path is changed under the action of the guide plate 2-1 in Figure 2. The guide plate plays a role in changing the flow path of the gas phase working medium. After the liquid working medium is heated and evaporated, it becomes It turns into a gaseous state, and the gas phase working medium is heated and rises. However, due to the blocking effect of the baffle, the gaseous fluid cannot be discharged from the top layer inside the evaporator and can only be discharged from the microchannel below the baffle. When the liquid fluid continues to absorb heat and the vaporization process continues, more and more gas accumulates in the manifold evaporator cavity. Under the action of the baffle 2-1 in Figure 2, the gas will move downward and pass through The baffle 2-1 then moves upward and enters the exhaust channel 2-8, and then the steam enters the outflow channel and is finally discharged from the outlet. The gas transfer path of the evaporator of the present invention is different from the traditional microchannel bottom plate. This transfer path can effectively reduce the gas flow resistance and take away more heat per unit time. The liquid overflows the microchannel and accumulates in the first part, and then flows to the outlet 2-3 through the second part. The liquid volume is not very large, and most of it has been vaporized, so the length of the first part does not need to be very long. The microchannel is connected to the first part, so that the overflowed liquid after heat exchange enters the first part.

The fluid ammonia changes into a two-phase state after passing through the microchannel 2-5 in Figure 3. The fluid ammonia flows into the slope V-shaped groove 2-7 in Figure 3. The V-shaped groove with its own slope has a guiding effect, which can make the two phases Fluid ammonia automatically flows along the channel toward the outlet, collects and is stored at the outlet; at the same time, the V-shaped designed channel can make the liquid level reach the highest level, allowing the liquid to flow smoothly into the outlet pipe under the minimum driving force, eliminating excess liquid. The discharge efficiency of the fluid is maximized, and the fluid is discharged from the evaporator through the outlet and flows into the outlet pipeline.

The significance of designing the slope V-shaped grooves 2-7 in Figure 3 is to reduce the driving force required for liquid to converge to the outlet and reduce the energy consumption required for device operation; at the same time, the V-shaped grooves 2-7 in Figure 3 can allow the liquid to automatically gather and It is stored in the middle area to maximize the liquid discharge efficiency, prevent excessive liquid accumulation and backflow, and is more conducive to the stable operation of the protection device.

Preferably, the cover plate is engraved with grooves to facilitate cooperation with the bottom plate and ensure good sealing.

Preferably, the heat source to which the evaporator is thermally connected is an electronic device. Meet the high heat flux density cooling requirements of integrated electronic devices.

The liquid reservoir is responsible for fluid storage, supply, precise temperature control and vapor-liquid separation. In the pump-driven two-phase fluid circuit, the fluid flow in the evaporator and liquid reservoir is in a two-phase saturated state, and its saturation pressure is linearly related to the saturation temperature. This liquid reservoir maintains a constant saturation pressure in the entire liquid reservoir by controlling the temperature in the small liquid storage tank, thereby ensuring that the fluid in the evaporator is stable at the corresponding saturation temperature. The liquid reservoir is in a two-phase state. The liquid reservoir plays the role of vapor-liquid separation. There is a phase change of the working fluid in the loop. The phase change will affect the volume of the working fluid. Gasification increases the volume and liquefaction reduces the volume. A liquid storage device is required for buffering. , when too much working fluid is not needed in the loop, the excess working fluid is stored in the liquid storage tank. When the working fluid comes out of the condenser, if it is in a two-phase state, the liquid storage tank can carry out vapor-liquid transfer through the porous partition. separation.

Preferably, as shown in Figure 5, the liquid storage tank 4 is divided into a large liquid storage tank 4-3 and a small liquid storage tank 4-7. The top of the small liquid storage tank 4-7 and the top of the large liquid storage tank 4-3 The bottom of the small liquid storage tank 4-7 and the bottom of the large liquid storage tank 4-7 are connected through the bottom pipeline, and the top pipeline and the bottom pipeline are respectively provided with solenoid valves 4-1.

A large amount of liquid fluid is stored in the large liquid storage tank, which can realize fluid exchange with the main circuit. When filling liquid fluid from the outside, the liquid fluid is continuously injected into the large liquid storage tank from the filling port (in Figure 5) 4-2 at the upper end of the large liquid storage tank, and then fills the entire circuit. In a pump-driven two-phase fluid circuit, the saturation pressure in the liquid reservoir determines the saturation temperature when the fluid phase changes. In order to maintain the saturation temperature, the temperature of the liquid reservoir needs to be controlled to maintain the saturation pressure. Considering that it is relatively difficult to directly change the temperature of the liquid in the large liquid storage tank, the team introduced a small liquid storage tank in addition to the large liquid storage tank. The two tanks were connected and indirectly controlled the large liquid storage tank by controlling the temperature and pressure in the small liquid storage tank. internal pressure to maintain a constant saturation pressure. The top and bottom of the large liquid storage tank and the small liquid storage tank are connected by pipelines respectively, and a solenoid valve (Figure 5) 4-1 is installed in the middle of the two pipelines. Before the system starts working, the lower solenoid valve opens and the upper solenoid valve closes; after the system starts working, the upper solenoid valve opens to ensure equal pressure inside the two liquid storage tanks, and the lower solenoid valve closes to separate the liquid phases in the two tanks.

Heating piece and solenoid structure in the small liquid storage tank: In order to control the temperature in the small liquid storage tank (Figure 5) 4-7, install heating rods (Figure 5) 4-6 and Solenoid (Figure 5) 4-8 to achieve heating and cooling respectively. Since active cooling of the liquid in the small storage tank requires a certain amount of energy and the existing subcooled fluid in the loop can meet the cooling needs of the small storage tank, the team decided to pass a part of it into the solenoid and condense it through condenser 3. This part of the supercooled fluid flows through the solenoid and then returns to the main circuit. The temperature difference between the subcooled fluid and the liquid in the small storage tank is used to cool the liquid in the tank, saving the need for refrigeration. of additional energy consumption. The adjustment of cooling efficiency is achieved by controlling the flow of subcooling fluid through a valve at the inlet of the solenoid.

Porous partition at the outlet of the large liquid storage tank: The space in the large liquid storage tank (Figure 5) 4-3 other than the liquid fluid is filled with gas-phase working medium. In order to achieve vapor-liquid separation and prevent the gas-phase working medium in the liquid storage tank from entering The main loop caused cavitation of the mechanical pump. The team installed a sintered porous partition (Figure 5) 4-11 at the outlet of the large liquid storage tank. The capillary pores on it can effectively block the gas phase working medium while flowing the liquid fluid, preventing The gas phase working fluid enters the main loop.

Placement of sensors: Install temperature sensor (Figure 5) 4-9 and pressure sensor (Figure 5) 4-4 on the small liquid storage tank (Figure 5) 4-7 to provide real-time feedback of the temperature and pressure in the tank, so as to Adjust the heating efficiency of the heating rods (Figure 5) 4-6 and the cooling efficiency of the solenoid (Figure 5) 4-8. In addition, in order to detect changes in the liquid level in the liquid storage tank in real time, liquid level gauges (Fig. 5) 4-5, heating rod 4-6.

When the fluid comes out of the condenser, if it is in a two-phase state, the liquid reservoir can separate vapor and liquid through the porous partition. Preferably, the cooled liquid ammonia first enters the liquid reservoir and is then driven by a mechanical pump for the next cycle.

Preferably, as shown in Figure 8, the condenser includes a spray box (left) and a water storage box (right). Each of the two boxes has an inlet at the top and an outlet at the bottom. During spraying, the gaseous hot fluid is injected into the sprinkler head from the top nozzle, diffuses into the box, exchanges heat with the heat pipe and becomes liquid, flows out from the bottom nozzle, and enters the next pump-driven two-phase cycle. Cold water in the water storage tank is injected from the top nozzle, and hot water is released from the bottom nozzle. The heat pipe in the spray box is inserted into the water storage box at a certain angle. Correspondingly, the spray direction of the sprinkler head is also tilted at a certain angle, thereby ensuring that the large end of the heat pipe fully contacts the sprayed hot fluid during spraying, achieving high efficiency exchange. The purpose of heating is to ensure that the coolant in the heat pipe can flow back to the big end under the action of gravity for the next cycle after exothermic liquefaction at the small end. In addition, the heat pipes in the spray box are arranged in a fork row to increase the contact area between the large ends of the heat pipes and the sprayed hot fluid.

When the heat generated by the heat source increases, more liquid phase fluid in the evaporator 2 changes to the gas phase, the volume of the gas phase increases, and the pressure in the loop is higher than the saturation pressure. At this time, the excess liquid phase fluid inside the loop will flow into the large liquid storage tank. (Figure 5) 4-3 is stored, and at the same time, the supercooled fluid in the solenoid (Figure 5) 4-8 cools the liquid in the small liquid storage tank (Figure 5) 4-7, so that the two liquid storage tanks The overall pressure of the tank decreases, and the pressure in the loop immediately drops to the saturation pressure; conversely, when the calorific value of the heat source decreases, the calorific value decreases, a small amount of liquid phase fluid in the evaporator changes to the gas phase, the volume of the gas phase decreases, and the pressure in the loop is lower than At this time, the insufficient fluid in the circuit will be replenished by the large liquid storage tank. At the same time, the heating plates (Figure 5) 4-10 heat the liquid in the small liquid storage tank, causing the overall pressure of the two liquid storage tanks to increase. , the pressure in the loop immediately rises to the saturation pressure. When the liquid reservoir replenishes the fluid in the main circuit, the porous partition plate (Figure 5) 4-11 at the liquid reservoir outlet can block the gas phase working medium in the tank and prevent it from entering the main circuit and causing cavitation of the mechanical pump.

Preferably, a flat tube is provided in the regenerator 6, and the fluid from the evaporator flows in the flat tube. A fusiform structure fin array is arranged inside the flat tube. For the spindle-shaped structure fin array, please refer to the records in the previous application numbers (CN202210267306.8, CN202210267339.2, CN202210267340.5, CN202210267351.3). All features of the spindle-shaped structure fin array described above are cited in this application. middle. The invention is equipped with a new type of fusiform structure fin, which can make the fluid flow along the fin and improve the heat exchange efficiency.

There are multiple fin arrays, and two adjacent fin arrays are connected end to end. Each fin array is divided into multiple layers, and each array includes a central fin and multiple layers of peripheral fins surrounding the central fin, and each layer of fins is a spindle-shaped structure. By setting up multiple layers, the fluid can fully flow and exchange heat therein.

A plurality of fin arrays form a group. The head of the first fusiform structure of each group is opposite to the flow direction of the liquid (facing the fluid flow direction). The tail of the first fusiform structure is in contact with the head of the second fusiform structure. Connect, and so on, to form a group. By arranging multiple layers, the fluid can fully flow and exchange heat therein, and the flow channel of the fluid continues to undergo frequent flow and volume changes along the shuttle shape with the flow, further improving the heat exchange efficiency.

The head and tail of the fusiform structure are both pointed. The angle between the tips of the head of the fusiform structure is smaller than the angle between the tips of the tail. The isomorphic structure above allows the fluid to first spread slowly along the shuttle shape, avoiding the low heat transfer effect caused by rapid diffusion, promoting heat transfer, and at the same time promoting the guidance of the fluid to make it consistent with the previous capillary structure. Further cooperation improves evaporation efficiency.

Preferably, the connection line of the central fins of each group is in the same direction as the fluid flow.

Preferably, multiple sets of fin arrays are arranged in parallel.

Preferably, the fins are elastic components. The elastic components can cause the fluid to wash away the heat conductor when flowing. The fins will oscillate pulsatingly to promote descaling, and the vibration will cause flow disturbance and also enhance heat transfer.

Preferably, along the direction of fluid flow in the flat tube, the elasticity of the fins first becomes smaller and then becomes larger. Because as research has discovered, as the fluid enters the flat tube, due to the sudden increase in volume, the pressure becomes smaller, causing part of the liquid carried to continue to form vapor, which increases the impact and is less likely to scale, so the elasticity of the setting begins to gradually Decrease, with the subsequent heat exchange and condensation, the fluid is more likely to foul, and the scale becomes more and more serious along the direction of fluid flow. Therefore, by setting the elasticity degree to continuously increase, the purpose of further descaling and strengthening heat transfer has been achieved, and the large scale reduction has been achieved. Elastic thermal conductor reduces costs. Through the above settings, heat exchange and descaling can be further realized quickly, and costs can be saved at the same time, so that the best effect and the lowest cost can be achieved.

Further preferably, along the direction of fluid flow in the flat tube, the elasticity of the thermal conductor decreases to a smaller and smaller extent, and then increases to an increasing extent. The above changes are also found based on research and are in line with the rules of scaling, which can further reduce costs, improve heat exchange efficiency, and reduce scaling. To achieve the best results and lowest cost.

Figure 8 The condenser is composed of a spray box 3-2 and a heat storage box 3-4. The water in the heat storage box 3-4 on the right side of Figure 8 absorbs heat and heats up to store heat. At the same time, the water on the left side of Figure 8 The gas phase in the original two-phase fluid in the spray box 3-2 exothermicly liquefies and condenses into a liquid phase. Based on the principle that the liquid state of a substance is denser than the gaseous state, the liquid phase fluid flows downward into the liquid storage tank 4 in Figure 1 and is filtered. The device flows back into the pipeline to achieve the purpose of recovering low-grade waste heat. The main power is provided by the pump 5 for the circulating flow of fluid between the evaporator 2 and the condenser 3 in Figure 1. This reciprocating cycle achieves efficient heat exchange.

The condensing unit includes a spray box and a water storage box. Each of the two boxes has an inlet at the top and an outlet at the bottom. During spraying, the gaseous hot fluid is injected into the sprinkler head from the top nozzle, diffuses into the box, exchanges heat with the heat pipe and becomes liquid, flows out from the bottom nozzle, and enters the next pump-driven two-phase cycle. Cold water in the water storage tank is injected from the top nozzle, and hot water is released from the bottom nozzle. The heat pipe in the spray box is inserted into the water storage box at a certain angle. Correspondingly, the spray direction of the sprinkler head is also tilted at a certain angle, thereby ensuring that the large end of the heat pipe fully contacts the sprayed hot fluid during spraying, achieving high efficiency exchange. The purpose of heating is to ensure that the coolant in the heat pipe can flow back to the big end under the action of gravity for the next cycle after exothermic liquefaction at the small end. In addition, the heat pipes in the spray box are arranged in a fork row to increase the contact area between the large ends of the heat pipes and the sprayed hot fluid.

The heat pipe unit includes the evaporation end, condensation end 3-1-1, silicone gasket 3-1-2, fastening plate 3-1-3, thermal fins 3-1-4, heat pipe plug 3-1-5, and capillary core 3-1-6, heat pipe shell 3-1-7. The heat pipe shell between the evaporation end and the condensation end is provided with a fastening plate, and a silicone gasket is provided on the upper side of the fastening plate, and the silicone gasket is pressed by the fastening plate for sealing.

The heat pipe includes a big end and a small end. The diameter and length of the big end are larger than that of the small end. The big end of the heat pipe is inserted into the spray box, and the small end of the heat pipe is inserted into the water storage box. Preferably, fins are provided outside the big end. By providing fins, the balance of heat absorption and heat release can be better achieved. By setting the big end and the small end, the heat absorption and heat release on both sides can be evenly balanced, preventing one side from absorbing heat too slowly and the other side from releasing heat too quickly, and preventing the heat pipe from drying out and being damaged.

When the gas-phase hot fluid flows into the shower head, the shower head evenly spreads the hot gas to the heat pipe fins. When the large-end heat-conducting fins come into contact with the hot gas, the heat of the hot gas is transferred to the heat-conducting fins, and then to Inside the heat pipe body. There is a two-phase fluorinated coolant inside the heat pipe. The coolant absorbs heat and vaporizes. The gas is heated and rises to the small end of the heat pipe. At this time, the small end of the heat pipe is surrounded by external cold water, and the temperature difference is large, so that the heat of the gas is conducted to the outer wall. At this time, the water absorbs heat and heats up, and the hot gas releases heat and cools down to condense. The condensed liquid fluorinated coolant then flows back along the tube wall to the big end of the heat pipe, thereby realizing a reciprocating cycle of heat dissipation.

In order to improve the heat absorption efficiency of the two-phase fluid inside the heat pipe, long strips of capillary wicks 3-1-6 are built into the big end, and are arranged staggered up and down to maximize the use of the effective heat exchange area when guiding the fluid to flow to the evaporation end. The capillary core is made by metal sintering method, and a special mold is filled with metal powder and pore-forming agent in a ratio of 1:1. The existence of the capillary core will provide a large number of micropores, which can absorb the two-phase fluid in a shorter time and quickly cause its endothermic phase change, greatly improving the heat exchange efficiency of the heat pipe.

The external threads and internal threads at a (set at the small end close to the silicone gasket) and b are both convenient for disassembly. The external thread at the small end of the heat pipe at a is screwed with the side wall of the water tank, and is realized with the fastening plate and silicone gasket. Good sealing; b is located at the internal thread at the tail of the large end of the heat pipe and the external thread at the outer wall of the heat pipe plug, which facilitates the replenishment or replacement of the two-phase coolant in the heat pipe, and also facilitates the replacement and repair of the capillary core.

Although the present invention has been disclosed above in terms of preferred embodiments, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be subject to the scope defined by the claims.

Claims (7)

1. A condenser, including a spray box and a water storage box. The spray box and the water storage box each have an inlet at the top and an outlet at the bottom. The heat pipe connects the spray box and the water storage box. , the heat pipe in the spray box is inserted into the water storage box at a certain angle upwards. When spraying, the gaseous hot fluid is injected into the sprinkler head from the top nozzle, diffuses into the box, exchanges heat with the heat pipe, and becomes liquid. The pipe flows out and enters the next pump-driven two-phase cycle; cold water in the water storage tank is injected from the top pipe, and hot water is released from the bottom pipe. 2. The condenser according to claim 1, characterized in that a sprinkler head is arranged on the upper part of the sprinkler box, and the spray direction of the sprinkler head is inclined at a certain angle, and the inclination direction is consistent with the inclination direction of the heat pipe. 3. The condenser of claim 1, wherein the heat pipes in the spray box are arranged in a fork row to increase the contact area between the large ends of the heat pipes and the sprayed hot fluid. 4. The condenser of claim 1, wherein the heat pipe includes a large end and a small end, the large end of the heat pipe is inserted into the spray box, and the small end of the heat pipe is inserted into the water storage box. 5. The condenser according to claim 4, wherein the large end is provided with heat conduction fins. 6. The condenser of claim 5, wherein the diameter and length of the large end are larger than those of the small end. 7. A waste heat recovery loop heat pipe system, including a preheater, evaporator, condenser, liquid reservoir, pump and recuperator. The preheater, evaporator, condenser and liquid reservoir are connected in sequence through pipelines. , the liquid reservoir is connected to the regenerator through a pipeline, a pump is provided on the pipeline between the liquid reservoir and the regenerator, and the regenerator is connected to the preheater through the pipeline; the condenser is one of claims 1-6 One condenser.