GR1009535B - Thermal energy generation via the cavitation effect - Google Patents

Abstract

The invention takes advantage of the cavitation effect utilized for the generation of heat via thermal bodies 4 (fig.2), by creating a cylindrical hourglass-like tube 10 or an array of plural cylindrical tubes via a cutting device-lathe, which tubes are of precise dimensions and made of teflon PTFE or translucent acrylic plastic or other related material. With regard to the type of the pump 1 and its peculiar curves, the related thermal energy can be generated by using the cylindrical tube 10 which is perforated in the Venturi-type shape and bears precise internal dimensions. A significant quantity of heat can be generated by the properly placed cylindrical tube 10. Advantages: drastic reduction of the pump’s blades destruction caused by the cavitation effect exploited for thermal energy generation. Embodiment: the invention finds application to existing installations operating with one or more water pumps, e.g. pumping stations meant to heat up spaces found inside the installation or in other separate spaces.

Description

Thermal energy production system through cavitation effect

Patent Description.

The present invention refers to a heat production system through an hourglass-veduri type device that we propose, and the device that we propose in the present invention provides the possibility to convert the kinetic energy of water into thermal energy, through the cavitation effect.

Cavitation is considered to be one of the main factors of mechanical corrosion of metal solid surfaces in industrial systems due to the heat developed locally, causing chemical reactions.

With the present invention we take advantage of the phenomenon of cavitation and above all the possibility of using it for heat production through heating bodies, creating a cylindrical tube in the form of an hourglass 10 (figure 2) or an array of more cylindrical tubes 10 (figure 2) depending on the thermal energy which we need, with specific dimensions of Teflon PTFE material or transparent acrylic plastic or other related material. Our tube has a Venturi shape (figure 1).

The system can be applied either in any space or in existing installations where one or more water pumps work, e.g. In pumping stations when we want to heat various spaces inside the installation.

By implementing this system we propose, we also have the important advantage of drastically reducing the destruction of the vanes of our pump 1 (figure 2) from the cavitation phenomenon by taking advantage of the thermal energy created by this phenomenon. We do not need to consume additional electricity or other forms of energy to heat the auxiliary spaces in already existing facilities where one or more water pumps work, e.g. workshops - offices - w.c. Zero maintenance required.

Background of the invention. There are two branches of fluid mechanics: fluid statics which deals with fluids in equilibrium and fluid dynamics with fluids in motion. Hydrodynamics is a special branch of Fluid Mechanics, i.e. Hydromechanics and especially Dynamics. In a pipe whose cross-section is not the same everywhere, the velocity of the liquid changes (equation of continuity). The Venturi effect consists in reducing the pressure of fluid flowing in a narrowing tube and its operation is based on Bernoulli's law. Inside a pipe of variable diameter, Bernoulli's equation gives the relationship between the velocity, pressure and lift of a fluid as it moves. The volume of the fluid that flows per unit of time at a random point in the pipe is given by the product of the velocity and the cross-sectional area of the pipe. If the fluid is incompressible, equal amounts of fluid flow into and out of the pipe. Therefore the continuity equation applies: A1*V1 = A2*V2 (figure 1) where A1 and A2 (figure 1) are the cross-section and V1 and V2 (figure 1) are the velocity of the fluid in the tube of different diameter. Unit of measurement of the fluid supply is 1m3 /sec.

Cavitation is the formation of vapor bubbles in a flowing liquid at the point where its pressure drops below the vapor pressure, developing a high temperature. The resulting bubbles pass from their birth phase 6 (figure 2) to their collapse phase 5 (figure 2) when they are in the high pressure field. During the collapse of the cavitation bubble 5 (figure 2), a sequence of phenomena is created in the bubble core that results in the development of high temperatures and pressures as well as the emission of light.

When, where and to what extent we will have cavitation, depends on the type of impeller of our pump, and the speed with which it will move through the water. However, the thinner the impeller, the more likely it is not to show cavitation.

In figure 1: We see a vertical section of the cylindrical tube-hourglass 10 (figure 2) which is divided into five sections, section A, section B, section C, section D and section E with different diameters A1 and A2 per section, with different pressures P1 and P2 per section, and different water flow velocities V2 per section, the two different slopes from section B to section C with a 25 degree slope and from section C to section D with a 40 degree slope as well as the negative pressure received by the water flow in section C with height h1.

In figure 2: We see in a vertical section the cylindrical tube-hourglass 10 (figure 2) where the hydraulic thread 7 and 7a can be distinguished (figure 2), the size of the bubbles 6 (figure 2) in the phase of their birth the size of the bubbles 5 (figure 2) in their collapse phase, as well as a full view of the cylindrical tube-hourglass 10 (figure 2) where arrow 11 (figure 2) indicates the water flow inlet and arrow 12 (figure 2) the water flow outlet from the cylindrical tube-hourglass 10 (figure 2). The complete thermal energy production system can also be seen in a complete arrangement with the correct order of connection of the components, from the recirculation pump 1 (figure 2) and the depression 8 (figure 2) to the connection point 7 (figure 2) of the hourglass 10 (figure 2 ), from the connection point 7a (diagram 2) of the hourglass 10 (diagram 2) to the pipe - duct 2 (diagram 2), from the pipe - duct 2 (diagram 2) through the nozzle 13 (diagram 2) on the upper part of the heater body 4 (diagram 2), from the bottom of the heating body 4 (diagram 2) through mouthpiece 13 (diagram 2) to the pipe - duct 3 (diagram 2) and finally to the suction 9 (diagram 2) of the recirculation pump 1 (diagram 2).

Detailed description of the proposed application: In our case taking into account the above and according to (figure 1) and (figure 2) we created a cylindrical tube 10 (figure 2) with different variable cross-sections A1,A2 (figure 1) with A1>A2 , which when we supply it with a forced flow of water we notice that we have different water pressures P1, P2 (figure 1) with P1>P2 and different speeds V1, V2 (figure 1) with VKV2, and it has the shape of an hourglass (figure 1) and 10 (figure 2). In addition to one cylindrical tube, we can also use an array of several cylindrical tubes depending on the amount of water and the thermal power we want.

The cylindrical Venturi 10 tube (figure 2) has specific dimensions, made of transparent acrylic plastic to avoid any corrosion on its walls. But the most basic element of this device, as can be seen in the vertical section of the Venturi-shaped cylindrical tube (figure 1), are the variable cross-sections in sections A, B, C, D, E (figure 1) that show the difference between the original cross-section of the tube before constriction in section A (figure 1), the narrow cross-section in section C (figure 1) and the final cross-section in section E (figure 1). This difference is proportional to the square of the supply. The angles of inclination from section B (figure 2) to section C (figure 2) of the pipe should be 25 degrees and from section C (figure 2) to section D (figure 2) of the pipe should be 40 degrees . So with the proper supply we can get the proper relationship. We see in (figure 1) the shape of the curve that the hydraulic pressure makes as well as the negative pressure in the curve with height hi (figure 1), so depending on the characteristic curves and the type of pump, we use the corresponding cylindrical pipe (figure 2) or parallel array thereof. The total length of the cylindrical tube 10 (figure 2) from the end of section A to the end of section E (figure 2) and depending on the type of pump will be no more than 35 cm, with an overall diameter of 3" inches or 7.62 cm (how many cylindrical pipes we will place in parallel depends on the characteristics of our pump 1 (figure 2) and the space we want to heat).

We place the cylindrical tube 10 (figure 2) on a cutting machine - lathe or (on a CNC through a CAD/CAM system) from the side of section A (figure 2) where an opening is made internally in the center and along the entire length of the cylindrical tube of a hole with a φ17 rim. Internally and from the end of section A (diagram 2) an opening of diameter φ50 is made through the cutting machine in a length of 10cm, we continue the opening with an inclination of 25° degrees from section B (diagram 2) to section C (diagram 2) until we meet the hole with a diameter of φ17. We rotate the cylindrical pipe 10 (fig. 2) in the cutting machine and from the side of section E (fig. 2), a hole is made in the middle of the cutting machine with a diameter of φ50 to a length of 10 cm, we continue the hole with an inclination of 40° degrees from the section D ( figure 2) in section C (figure 2) until we meet the hole with a diameter of φ17. The total length of section C (figure 2) should be 9.49cm after the cylinder tube is fully opened. Externally and at the ends of the section A (figure 2) and E (figure 2) of the cylindrical tube - hourglass 10 (figure 2) we create hydraulic threads 7 and 7a (figure 2) respectively with a thread angle of 55 degrees and 11 turns per inch, through of a die or through the cutting machine.

The 35 cm long hourglass tube 10 (figure 2) is now ready for use.

In a network of a pumping station and an already installed recirculation pump 1 (diagram 2) inside our space we find the depression 8 (diagram 2) of the pump 1 (diagram 2), receiving part of the water flow coming out of the depression 8 (figure 2) of our pump 1 (figure 2) (the point we choose from the pressure mouthpiece), we place by screwing on the pressure mouthpiece 8 (figure 2) of pump 1 (figure 2) the hourglass 10 (figure 2) which we created through the hydraulic thread 7 (figure 2) that it has in section A (figure 2). From the end of section E (figure 2) which also has a hydraulic thread 7a (figure 2), we connect a pipe - conduit 2 (figure 2) with a mouthpiece 13 (figure 2) the upper part of a heating body 4 (figure 2) or (of several heaters and in parallel connection between them). From the bottom of the heating body 4 (fig. 2) we connect through a mouthpiece 13 (fig. 2) and pipe - conduit 3 (fig. 2) to the suction 9 (fig. 2) of the pump 1 (fig. 2), the cross section of the pipe - of pipe 2 (figure 2) and 3 (figure 2) depends on the number of heaters we want to heat. By starting the pump 1 (figure 2), we see that the water entering the hourglass 10 (figure 2) from the depression 8 (figure 2) with a dynamic pressure P1 in the section A (figure 2) enters the section B (figure 2) where the narrowing of the pipe is created with an inclination of 25° degrees, it enters section C with pressure P2 (figure 2) in which, due to the narrowing, bubbles 6 (figure 2) and the phenomenon of cavitation begin to be created. In section C (figure 2) due to the narrowing we have a drop in pressure, the lower this pressure becomes the more bubbles 5 (figure 2) are created and the cavitation phenomenon increases. Also, when the pressure at the constriction point C (figure 2) becomes lower than the atmospheric pressure, then air also enters the installation.

Millions of tiny bubbles are created in the water, thanks to the positive and negative pressure waves. Bubbles initially subjected to alternating pressure waves have a minimum size of about d=0.10pm 6 (figure 2) and continue to grow until they reach a certain size of about d=50μm 5 (figure 2), (1 centimeter [cm] = 10000 microns [μm]). Just before their collapse in section D (figure 2) and E (figure 2) a very large amount of energy has been collected within the bubble itself. From section C (figure 2) the bubble passes with an inclination of 40° degrees to section D (figure 2) and then to section E (figure 2) of the pipe where a high collapse of the bubble is created. During the collapse of the cavitation bubble 5 (figure 2), a sequence of explosions is created in its core which results in the development of high temperatures resulting in heating and the water begins to boil because the explosion of the steam bubbles occurs. Bubbles and boiling are maintained as long as water flow is maintained within the hourglass 10 (Figure 2). The temperature inside a cavitation bubble can be extremely high up to 3,000 °C, with pressure as high as 10,000 PSI.

As they collapse the bubbles will release the energy it took to create them in the form of a large amount of heat. This mutation of the bubbles releases energy that has the effect of heating the water that passes to the entrance of the heating body 4 (figure 2) that we want to heat. Placing our cylindrical pipe 10 (figure 2) in series with the discharge 8 (figure 2) of the water pump 1 (figure 2) or in parallel to an already installed water recirculation network in a pumping station from a nozzle of a recirculation pump 1 (figure 2) in the direction from the depression 8 (figure 2) to the suction 9 (figure 2) and putting one or more heating bodies 4 (figure 2) after the hourglass 10 (figure 2) we have heat production and in fact significant, reaching approximately an efficiency of 1 to 1.1 of the energy we give. For example if we give 1 Kw of electricity we will get up to 1.1 Kw of heating energy (Watt = Joule/sec).

The continuous recirculation of water, the so-called loop, creates the heating we desire. The desired temperature we want in our space is controlled through a room thermostat and an electric water valve placed before the radiator 4 (figure 2).

With the combination of pressure, temperature and speed, due to the very small size and the relatively high energy, we may have a loss of water, so we put an expansion tank in our closed circuit.

Our device can be applied to already existing installations where systems with one or more water pumps work, for example pumping stations where we would like to heat various auxiliary spaces located in the installation, but also individually in other spaces that we wish.

Claims (3)

Claims 1. Thermal energy production system through a cavitation effect from a device mounted on a water recirculation pump 1 (figure 2), converts kinetic energy into thermal energy, characterized by being composed of a cylindrical tube having the shape of an hourglass 10 (figure 2) or an array of several cylindrical tubes, it is perforated in a Venturi shape (figure 1), it has specific internal dimensions, depending on the type of pump 1 (figure 2) and its characteristic curves we get the corresponding thermal energy, the cylindrical tube - hourglass 10 (figure 2) has different angles of inclination from section B to section C (figure 2) and from section C to section D (figure 2), is made of Teflon PTFE material or transparent durable acrylic plastic or other related material, externally at its ends of section A and E (figure 2) has a hydraulic pass 7 and 7a (figure 2) respectively. 2. According to claim 1, the hourglass tube 10 (figure 2) can have an external shape other than the cylindrical one, have different dimensions and be made of any other corrosion-resistant material. 3. According to claim 1, in addition to one cylindrical tube - hourglass 10 (figure 2) an array of cylindrical tubes - hourglasses 10 (figure 2) connected in parallel can be placed, the proposed system (figure 2) can be applied for heating in already existing facilities where one or more water pumps 1 (figure 2) work or individually in other areas.