A compression card refrigeration system

Abstract

The application discloses a compression card refrigeration system, which comprises a hydraulic conveying structure, a regenerator structure, a cold end heat exchanger, a hot end heat exchanger and a piston structure. The regenerator structure comprises a shell, a heat exchange pipe, a liquid-state working medium inlet pipe, a cold end liquid inlet pipe, a cold end liquid outlet pipe, a hot end liquid inlet pipe and a hot end liquid outlet pipe. The input end of the cold end heat exchanger is communicated with the cold end liquid outlet pipe, and the output end is communicated with the cold end liquid inlet pipe through the piston structure. The input end of the hot end heat exchanger is communicated with the hot end liquid outlet pipe, and the output end is communicated with the hot end liquid inlet pipe through the piston structure. The application has the advantages that the hydraulic oil is transmitted and amplified to the liquid-state working medium through the hydraulic conveying structure, the phase change of the liquid-state working medium is driven by low pressure to realize the refrigeration effect, the cost is reduced, the energy consumption is reduced, the system is conducive to miniaturization design, and the compression card working medium is still wrapped outside the heat exchange pipe during the liquid-solid phase change of the pressurized liquid-state working medium, so that the heat exchange effect is improved and the heat exchange is uniform.

Description

Technical Field

[0001] This invention relates to the field of pressure-clamp refrigeration technology, specifically a pressure-clamp refrigeration system. Background Technology

[0002] Refrigeration technology is one of the key technologies in modern society, widely used in food preservation, medical storage, electronic device cooling, and many other fields. Traditional gas compression refrigeration systems mainly use vapor compression refrigeration cycles, transferring heat through the phase change of the refrigerant. However, these systems have several major problems: First, the environmental impact is becoming increasingly prominent. The refrigerants used in traditional gas compression refrigeration technology, such as chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), fluorocarbons (FCCs), and hydrofluorocarbons (HFCs), are harmful to the environment.

[0003] While gas compression refrigeration technology is quite mature, its theoretical efficiency remains limited, resulting in high energy consumption in practical applications, which does not meet current energy conservation and emission reduction requirements. A typical gas compression refrigeration system comprises multiple components such as a compressor, condenser, evaporator, and expansion valve, making the system complex, prone to failure, and costly to maintain.

[0004] To overcome the limitations of traditional gas compression refrigeration technology, researchers have begun exploring novel refrigeration technologies based on solid-state phase change. Solid-state refrigeration technology utilizes external fields (such as magnetic fields, electric fields, and stress fields) to induce a phase change in solid materials, achieving a refrigeration effect through the release and absorption of latent heat of phase change. It boasts significant advantages such as zero carbon emissions and high theoretical efficiency (up to 70% of Carnot efficiency). Among solid-state refrigeration technologies, pressure-based refrigeration technology has attracted widespread attention due to its unique advantages. Pressure-based refrigeration materials are a class of solid materials that undergo a solid-state phase change driven by pressure, releasing or absorbing latent heat of phase change. Using pressure-based materials as the working fluid and pressure as the driving force, pressure-based refrigeration technology is an emerging environmentally friendly solid-state refrigeration technology.

[0005] In recent years, pressure-sensitive material systems have developed rapidly, covering various types such as metals, inorganic non-metals, organic materials, and organic-inorganic hybrid materials. However, key refrigeration parameters of these materials, such as isothermal entropy change, have been difficult to exceed 100 J·K. -1 ·kg -1 The entropy change of poly(kJ / K) is far lower than that of gaseous refrigerants, which greatly limits the research progress of pyrocalant refrigeration systems. Later, researchers discovered the Poinciac effect in crystalline materials, whose isothermal entropy change is an order of magnitude higher than that of traditional solid-state phase change refrigeration materials, reaching a maximum of 687 J·K. -1 ·kg -1This material is comparable to a gaseous working fluid, laying a foundation for the development of pressurized refrigeration systems. Currently, Chinese invention patent document CN113587489A discloses a room-temperature pressurized refrigeration system based on this type of material. However, this type of material also has a significant problem: the driving pressure required to achieve a fully reversible pressurized effect is often very high, typically exceeding 200 MPa. This places extremely stringent requirements on the pressure resistance, sealing performance, and fatigue life of various parts of the refrigeration system, leading to high manufacturing costs, significant system reliability risks, and difficult maintenance. Furthermore, the refrigeration cycle under ultra-high pressure conditions also results in high energy consumption, reducing the system's heat exchange efficiency. Summary of the Invention

[0006] The technical problem to be solved by this invention is how to reduce the manufacturing cost of the press-fit refrigeration system and improve the heat exchange effect of the press-fit refrigeration system.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0008] A pressure-type refrigeration system includes a hydraulic conveying structure, a regenerator structure, a cold-end heat exchanger, a hot-end heat exchanger, and a piston structure. The regenerator structure includes a shell, heat exchange tubes, a liquid working fluid inlet pipe, a cold end inlet pipe, a cold end outlet pipe, a hot end inlet pipe, and a hot end outlet pipe. The shell contains multiple sets of heat exchange tubes and is filled with liquid working fluid that submerges the heat exchange tubes. The heat exchange tubes are filled with heat exchange fluid. The shell is provided with a liquid working fluid inlet pipe that is connected to the hydraulic conveying structure. The cold end inlet pipe, cold end outlet pipe, hot end inlet pipe, and hot end outlet pipe are all provided on the shell and are connected to the heat exchange tubes. The cold end inlet pipe and cold end outlet pipe, as well as the hot end inlet pipe and hot end outlet pipe, are respectively provided at both ends of the shell. The cold end heat exchanger's input end is connected to the cold end liquid outlet pipe, and its output end is connected to the cold end liquid inlet pipe through a piston structure. The input end of the hot-end heat exchanger is connected to the hot-end liquid outlet pipe, and the output end is connected to the hot-end liquid inlet pipe through a piston structure.

[0009] In this invention, since the liquid working fluid is always filled inside the shell, the pressure transmission and amplification from the hydraulic oil to the liquid working fluid is achieved through a hydraulic delivery structure. This allows for the use of low pressure to drive the phase change of the liquid working fluid and achieve a cooling effect. This not only eliminates the need for ultra-high pressure equipment, reducing costs, but also decreases energy consumption, which is beneficial for the miniaturization of the refrigeration system. Furthermore, because the liquid working fluid remains encased outside the heat exchange tubes during the liquid-solid phase change after pressurization, this not only improves the heat exchange effect but also ensures uniform heat exchange.

[0010] Preferably, the shell includes a shell body, a left end cover, a right end cover, a left fluid pipe, and a right fluid pipe. The left end cover and the right end cover are respectively sealed to both ends of the shell body. The left fluid pipe is sealed to the left end cover, and the right fluid pipe is sealed to the right end cover. One end of the heat exchange pipe passes through the left end cover and communicates with the left fluid pipe. The other end of the heat exchange pipe passes through the right end cover and communicates with the right fluid pipe. The cold end liquid inlet pipe and the hot end liquid outlet pipe are arranged on the left fluid pipe and communicate with its inner cavity. The hot end liquid inlet pipe and the cold end liquid outlet pipe are arranged on the right fluid pipe and communicate with its inner cavity.

[0011] Preferably, sealing rings are fitted on the outer walls of both ends of the heat exchange tube.

[0012] Preferably, the hydraulic conveying structure includes a hydraulic station, an oil injection pipe, a pressure conversion pipe, a bidirectional piston, and a liquid working medium injection pipe. One end of the pressure conversion pipe is connected to the hydraulic station through the oil injection pipe, and the other end is connected to the liquid working medium inlet pipe through the liquid working medium injection pipe. The bidirectional piston is set inside the pressure conversion pipe and divides the inner cavity of the pressure conversion pipe into two parts, namely a first cavity filled with oil and a second cavity filled with liquid working medium.

[0013] Preferably, a pressure gauge is installed on the hydraulic station.

[0014] Preferably, the volume of the first cavity is larger than the volume of the second cavity.

[0015] Preferably, a pressure probe is provided on the pressure conversion tube of the second cavity.

[0016] Preferably, the piston structure includes a piston body and a drive motor. One end of the piston body is connected to the output end of the hot end heat exchanger and the cold end liquid inlet pipe, and the other end is connected to the output end of the cold end heat exchanger and the hot end liquid inlet pipe. The drive motor is electrically connected to the piston body and can drive the piston in the piston body to move, thereby driving the flow of heat exchange fluid in the press-fit refrigeration system.

[0017] Preferably, the inner wall of the housing is also provided with a Teflon liner.

[0018] Preferably, the liquid working medium is a liquid n-alkane working medium.

[0019] Compared with the prior art, the beneficial effects of the present invention are: 1. In this invention, since the liquid working fluid is always filled inside the shell, the pressure transmission and amplification from hydraulic oil to the liquid working fluid is realized through the hydraulic delivery structure. The cooling effect can be achieved by using low pressure to drive the phase change of the liquid working fluid. This not only eliminates the need for ultra-high pressure equipment and reduces costs, but also reduces energy consumption, which is beneficial for the miniaturization design of the refrigeration system.

[0020] 2. Because the liquid working fluid is pressurized and during the liquid-solid phase change, the pressurized working fluid is always wrapped around the outside of the heat exchange tube, which not only improves its heat exchange effect, but also makes the heat exchange uniform. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of an embodiment of the present invention; Figure 2 This is a schematic diagram of the hydraulic conveying structure according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the regenerator structure according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the piston structure according to an embodiment of the present invention; Figure 5 This is a simulation result diagram of the maximum temperature span between the hot and cold ends of the pressure card refrigeration system according to an embodiment of the present invention. Detailed Implementation

[0022] To facilitate understanding of the technical solution of the present invention by those skilled in the art, the technical solution of the present invention will now be further described in conjunction with the accompanying drawings.

[0023] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0024] In this application, unless otherwise expressly specified and limited, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise expressly and specifically limited.

[0025] See Figure 1 This embodiment discloses a pressure-cooling system, including a hydraulic conveying structure 1, a regenerator structure 2, a cold end heat exchanger 3, a hot end heat exchanger 4, and a piston structure 5.

[0026] See Figure 2The hydraulic conveying structure 1 includes a hydraulic station 11, an oil injection pipe 12, a pressure conversion pipe 13, a bidirectional piston 14, a liquid working fluid injection pipe 15, a pressure gauge 16, and a pressure probe 17. One end of the pressure conversion pipe 13 is connected to the hydraulic station 11 through the oil injection pipe 12, and the other end is connected to the regenerator structure 2 through the liquid working fluid injection pipe 15. The bidirectional piston 14 is disposed inside the pressure conversion pipe 13, dividing the inner cavity of the pressure conversion pipe 13 into two parts: a first cavity 131 filled with oil and a second cavity 132 filled with liquid working fluid. A pressure gauge 16 is disposed on the hydraulic station 11 to detect the hydraulic pressure inside the hydraulic station 11. In this embodiment, hydraulic oil is injected into the hydraulic station 11. A pressure probe 17 is disposed on the pressure conversion pipe 13 of the second cavity 132 to detect the pressure of the liquid working fluid inside the second cavity 132.

[0027] In this embodiment, the volume of the first cavity 131 is larger than that of the second cavity 132, so that injecting a small amount of hydraulic oil into the first cavity 131 can drive the bidirectional piston 14 to move towards the second cavity 132, thereby giving the liquid working medium in the second cavity 132 a greater pressure.

[0028] See Figure 1 and Figure 3 The regenerator structure 2 includes a shell 21, a heat exchange tube 22, a liquid working fluid inlet pipe 23, a cold end inlet pipe 24, a cold end outlet pipe 25, a hot end inlet pipe 26, and a hot end outlet pipe 27.

[0029] The housing 21 includes a housing body 211, a left end cap 212, a right end cap 213, a left fluid pipe 214, and a right fluid pipe 215. The left end cap 212 and the right end cap 213 are respectively sealed to both ends of the housing body 211. The left fluid pipe 214 is sealed to the left end cap 212, and the right fluid pipe 215 is sealed to the right end cap 213. The housing body 211 is provided with multiple sets of heat exchange tubes 22 and liquid working fluid filling the heat exchange tubes 22. The heat exchange tubes 22 are filled with heat exchange fluid. The housing body 211 is provided with a liquid working fluid inlet pipe 23 that communicates with the liquid working fluid inlet pipe 15, so that the second cavity 132 is connected to the inner cavity of the housing body 211 and filled with liquid working fluid. In this embodiment, the housing body 211 is also wrapped with a Teflon liner.

[0030] Specifically, one end of the heat exchange tube 22 passes through the left end cover 212 and is connected to the left fluid tube 214, and the other end of the heat exchange tube 22 passes through the right end cover 213 and is connected to the right fluid tube 215. The outer walls of both ends of the heat exchange tube 22 are fitted with sealing rings, so that the heat exchange tube 22 is sealed to the left end cover 212 and the right end cover 213 respectively, preventing the liquid working fluid in the inner cavity of the shell body 211 from leaking.

[0031] The cold end liquid inlet pipe 24 and the hot end liquid outlet pipe 27 are installed on the left fluid pipe 214 and communicate with its inner cavity, while the hot end liquid inlet pipe 26 and the cold end liquid outlet pipe 25 are installed on the right fluid pipe 215 and communicate with its inner cavity.

[0032] It should be noted that this embodiment uses a liquid working fluid as the pressing working fluid, which has the following comparative effects compared to existing solid pressing working fluids: 1. Existing solid pressurized working fluids require external ultra-high pressure equipment for pressurization due to their solid nature. However, ultra-high pressure equipment is more expensive and energy-intensive, and it is not conducive to the miniaturization design of the refrigeration system. In this application, since the liquid working fluid is always filled inside the shell body 211, the pressure transmission and amplification from hydraulic oil to the liquid working fluid is achieved through the hydraulic delivery structure 1. The refrigeration effect can be achieved by using low pressure to drive the phase change of the liquid working fluid. This not only eliminates the ultra-high pressure equipment and reduces costs, but also reduces energy consumption, which is conducive to the miniaturization design of the refrigeration system.

[0033] 2. In existing solid pressurized working fluids, the solid working fluid is compressed during pressurization, causing part of the heat exchange tube 22 in the solid working fluid to be exposed outside the solid working fluid. It is conceivable that its heat exchange effect is generally poor. However, in this embodiment, the liquid working fluid is always immersed in the heat exchange tube 22. After pressurizing the liquid working fluid, the pressurized working fluid is still always wrapped around the outside of the heat exchange tube 22 during the liquid-solid phase change. This not only improves its heat exchange effect, but also makes the heat exchange more uniform.

[0034] In this embodiment, the input end of the cold-end heat exchanger 3 is connected to the cold-end outlet pipe 25, and the output end is connected to the cold-end inlet pipe 24 via the piston structure 5; the input end of the hot-end heat exchanger 4 is connected to the hot-end outlet pipe 27, and the output end is connected to the hot-end inlet pipe 26 via the piston structure 5. It should be noted that valves are provided on the output ends of the cold-end heat exchanger 3 and hot-end heat exchanger 4, the cold-end inlet pipe 24, and the hot-end inlet pipe 26.

[0035] See Figure 4 The piston structure 5 includes a piston body 51 and a drive motor 52. One end of the piston body 51 is connected to the output end of the hot end heat exchanger 4 and the cold end liquid inlet pipe 24, and the other end is connected to the output end of the cold end heat exchanger 3 and the hot end liquid inlet pipe 26. The drive motor 52 is electrically connected to the piston body 51 and can drive the piston in the piston body 51 to move, thereby driving the flow of heat exchange fluid in the press-fit refrigeration system.

[0036] The working principle in this embodiment is as follows: When the cycle begins, open the valves on the hot-end inlet pipe 26 and the output end of the hot-end heat exchanger 4, and close the valves on the output end of the cold-end heat exchanger 3 and the cold-end inlet pipe 24. Then, the hydraulic station 11 injects oil and pressurizes the first chamber 131 through the oil injection pipe 12, driving the bidirectional piston 14 to move towards the second chamber 132, thereby pressurizing the liquid working medium in the second chamber 132. Observe the pressure on the pressure probe 17 and let it reach the set value. At this time, the liquid working medium in the circuit between the second chamber 132 and the inner cavity of the shell body 211 undergoes a liquid-to-solid transformation, releasing heat into the inner cavity of the shell body 211 and exchanging heat with the heat exchange fluid in the heat exchange tube 22 inside the shell body 211. The temperature of the heat exchange fluid rises, and the temperature of the working medium falls. At the same time, the piston in the piston body 51 is driven by the drive motor 52 to move towards the cold-end heat exchanger 3. Figure 4 (towards the right end of the piston body 51), thus allowing the heat exchange fluid to enter from the hot end inlet pipe 26, while the heat exchange fluid in the heat exchange tube 22 flows out from the hot end outlet pipe 27, passes through the hot end heat exchanger 4, and enters the end of the piston body 51 away from the cold end heat exchanger 3. Figure 4 (At the left end of the piston body 51), when the temperature detected at the inlet of the hot end heat exchanger 4 remains basically unchanged, the piston in the piston body 51 stops moving to the right end, thus releasing heat.

[0037] Then, hydraulic station 1 stops pressurizing, the pressure of the clamping working fluid is released, and the temperature of the clamping working fluid decreases. It then exchanges heat with the heat exchange fluid in heat exchange tube 22, causing the temperature of the clamping working fluid to rise and the temperature of the heat exchange fluid to drop. At this time, the piston in piston body 51 is driven by drive motor 52 to move towards the hot end heat exchanger 4. Figure 4 The piston body 51 is positioned to the left, allowing the heat exchange fluid to enter the heat exchange tube 22 from the cold end inlet pipe 24. The heat exchange fluid in the heat exchange tube 22 then flows from the cold end outlet pipe 25 to the cold end heat exchanger 3, and finally enters the right end of the piston body 51. When the temperature of the heat exchange fluid in the cold end outlet pipe 25 is detected to remain basically unchanged at the inlet of the cold end heat exchanger 3, the piston in the piston body 51 stops moving to the left, thus releasing the cold energy. After multiple pressurization and depressurization operations, the cooling operation can be achieved at the cold end until the target temperature is reached.

[0038] in addition, Figure 5 The figure shows the simulation results of the maximum temperature span between the hot and cold ends of the pressure refrigeration system in this embodiment. Specifically, it is based on the temperature evolution of the hot and cold ends obtained from finite element simulation. The results show that after 12 complete refrigeration cycles, the system can establish a maximum temperature span of about 12K, which proves the scientificity and feasibility of the pressure refrigeration system scheme in this embodiment.

[0039] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.

[0040] The above embodiments are merely examples of implementation methods of the invention. The scope of protection of the present invention is not limited to the above embodiments. For those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all fall within the scope of protection of the present invention.

Claims

1. A pressure-cooling system, characterized in that: This includes hydraulic conveying structures, regenerator structures, cold-end heat exchangers, hot-end heat exchangers, and piston structures. The regenerator structure includes a shell, heat exchange tubes, a liquid working fluid inlet pipe, a cold end inlet pipe, a cold end outlet pipe, a hot end inlet pipe, and a hot end outlet pipe. The shell contains multiple sets of heat exchange tubes and is filled with liquid working fluid that submerges the heat exchange tubes. The heat exchange tubes are filled with heat exchange fluid. The shell is provided with a liquid working fluid inlet pipe that is connected to the hydraulic conveying structure. The cold end inlet pipe, cold end outlet pipe, hot end inlet pipe, and hot end outlet pipe are all provided on the shell and are connected to the heat exchange tubes. The cold end inlet pipe and cold end outlet pipe, as well as the hot end inlet pipe and hot end outlet pipe, are respectively provided at both ends of the shell. The cold end heat exchanger's input end is connected to the cold end liquid outlet pipe, and its output end is connected to the cold end liquid inlet pipe through a piston structure. The input end of the hot-end heat exchanger is connected to the hot-end liquid outlet pipe, and the output end is connected to the hot-end liquid inlet pipe through a piston structure.

2. The pressure-cooling system according to claim 1, characterized in that: The shell includes a shell body, a left end cover, a right end cover, a left fluid pipe, and a right fluid pipe. The left end cover and the right end cover are respectively sealed to both ends of the shell body. The left fluid pipe is sealed to the left end cover, and the right fluid pipe is sealed to the right end cover. One end of the heat exchange tube passes through the left end cover and is connected to the left fluid pipe. The other end of the heat exchange tube passes through the right end cover and is connected to the right fluid pipe. The cold end liquid inlet pipe and the hot end liquid outlet pipe are set on the left fluid pipe and are connected to its inner cavity. The hot end liquid inlet pipe and the cold end liquid outlet pipe are set on the right fluid pipe and are connected to its inner cavity.

3. The pressure-cooling system according to claim 2, characterized in that: Both ends of the heat exchange tube are fitted with sealing rings.

4. The pressure-cooling system according to claim 1, characterized in that: The hydraulic transmission structure includes a hydraulic station, an oil injection pipe, a pressure conversion pipe, a bidirectional piston, and a liquid working medium injection pipe. One end of the pressure conversion pipe is connected to the hydraulic station through the oil injection pipe, and the other end is connected to the liquid working medium inlet pipe through the liquid working medium injection pipe. The bidirectional piston is set inside the pressure conversion pipe and divides the inner cavity of the pressure conversion pipe into two parts, namely a first cavity filled with oil and a second cavity filled with liquid working medium.

5. The pressure-cooling system according to claim 4, characterized in that: The hydraulic station is equipped with a pressure gauge.

6. The pressure-cooling system according to claim 4, characterized in that: The volume of the first cavity is larger than the volume of the second cavity.

7. The pressure-cooling system according to claim 4, characterized in that: A pressure probe is installed on the pressure conversion tube of the second chamber.

8. The pressure-cooling system according to claim 1, characterized in that: The piston structure includes a piston body and a drive motor. One end of the piston body is connected to the output end of the hot end heat exchanger and the liquid inlet pipe of the cold end, and the other end is connected to the output end of the cold end heat exchanger and the liquid inlet pipe of the hot end. The drive motor is electrically connected to the piston body and can drive the piston in the piston body to move, thereby driving the flow of heat exchange fluid in the press-fit refrigeration system.

9. A pressure-cooling system according to claim 1, characterized in that: The inner wall of the shell is also lined with Teflon.

10. A pressure-cooling system according to claim 1, characterized in that: The liquid working medium is a liquid n-alkane working medium.

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