A compression-release refrigeration system and method

Abstract

The application discloses a compression and throttling refrigeration system and method, which comprises injection pressurizing devices, cold end multi-stage warehouses, a regenerator, a high-pressure ball valve, a check valve and a hot end heat exchanger which are sequentially connected, the injection pressurizing devices comprise injectors, and the injectors are internally provided with a closed cavity structure. In the application, the injection pressurizing devices, the cold end multi-stage warehouses, the regenerator, the high-pressure ball valve, the check valve and the hot end heat exchanger form a refrigeration single loop, the structure is simple, miniaturization is easy, and the cost is reduced; the cold end heat exchanger warehouse, the cold end relaxation warehouse and the cold end cold warehouse which are sequentially connected and arranged in an S shape can inhibit the thermal disturbance of the pressure system to the cold end; the phase change temperature of the multi-stage compression and throttling working medium arranged in the regenerator is gradually increased from below room temperature to room temperature; after multiple cycles, a stable axial temperature gradient can be formed, the compression and throttling working medium with different phase change temperatures in the regenerator can work in the respective optimal phase change temperature zones, and the cold end cold warehouse can reach the target refrigeration temperature.

Description

Technical Field

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

[0002] Refrigeration technology, as a key technology supporting the operation of modern society, is indispensable in many fields such as food cold chain, medical refrigeration, and heat dissipation for electronic products. Currently, the widely used gas compression refrigeration cycle relies on the gas-liquid phase change of the refrigerant to transfer heat, but its application is accompanied by a series of significant problems. First, and most notably, is the environmental pressure; commonly used refrigerants such as chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), fluorocarbons (FCCs), and hydrofluorocarbons (HFCs) pose serious harm to the ecological environment. Second, although gas refrigeration technology is quite mature, its theoretical energy efficiency has an upper limit, and actual operating energy consumption is relatively high, which is incompatible with the goals of energy conservation and emission reduction. Furthermore, the gas system itself has a complex structure, encompassing multiple components such as compressors, condensers, evaporators, and expansion valves, resulting in a relatively high failure rate and expensive maintenance costs.

[0003] To overcome the limitations of traditional technologies, researchers have begun to focus on new cooling pathways based on solid-state phase change. These technologies utilize external fields (such as magnetic, electric, or stress fields) to drive a phase change in solid materials, achieving cooling through the absorption of latent heat during the phase change process. They offer advantages such as zero carbon emissions and high theoretical efficiency (reaching 70% of Carnot efficiency). Among numerous solid-state cooling solutions, press-calorie refrigeration technology has attracted particular attention in recent years due to the outstanding cooling parameters of press-calorie working fluids (taking NPG and solid-liquid phase change systems as examples, the isothermal entropy change is close to that of gaseous working fluids, an order of magnitude improvement compared to traditional phase change refrigeration materials). The excellent performance of press-calorie working fluids provides an important foundation for the research and development of press-calorie refrigeration systems. The pressure-cooling system is a complex system involving the coupling of multiple fields: pressure field, temperature field, and flow field. The pressure field is generally provided by a hydraulic system. The periodic application of pressure can make the pressure-cooling working fluid periodically absorb and release heat. In the above process, the heat exchange working fluid needs to have a coordinated periodic flow to directionally transport heat to the hot end of the regenerator and directionally transport cold energy to the cold end. This allows a temperature gradient to be gradually established in the regenerator, achieving a gradual temperature drop at the cold end.

[0004] Currently, although there are no formal reports on pressure-carrying refrigeration systems in the literature, related patents have been filed in China since 2021. Existing technical approaches mainly fall into two categories: 1) Those that do not rely on liquid pressure transmission, using the pressure-carrying working fluid itself as the pressure transmission medium. The main problem with this approach is the need for an ultra-high pressure system, uneven pressure distribution of the working fluid, and low heat exchange efficiency. This is because solids are not good pressure transmission media, and the pressure-carrying working fluid often has low thermal conductivity. Furthermore, the independent working fluid chamber is large, requiring thick walls to withstand pressure, all of which are detrimental to heat dissipation. 2) Liquid pressure transmission schemes. This approach can actually solve the problems of uneven pressure distribution and poor heat dissipation. For example, patent publication number CN113587489A discloses a room-temperature pressure-carrying refrigeration machine based on the pressure-heating effect. However, it involves complex heat transfer circuits and a large number of high-pressure valves, which will bring significant operating costs and failure rates to the system. Additionally, it causes thermal disturbance to the cold end. Summary of the Invention

[0005] The technical problem to be solved by this invention is how to provide a low-cost, simple-structured pressure-cooling system that can effectively suppress the thermal disturbance of the cold end by the hydraulic system.

[0006] This invention solves the above-mentioned technical problems through the following technical means: a pressure-pressurizing refrigeration system, comprising an injection pressurizing device, a cold-end multi-stage compartment, a regenerator, a high-pressure ball valve, a check valve, and a hot-end heat exchanger connected in sequence. The injection pressurizing device includes a syringe with a sealed cavity structure inside. A large piston and a small piston capable of synchronous reciprocating movement are located within the cavity. A sealing ring is fixed within the cavity. The large piston, sealing ring, and small piston divide the cavity into a first oil cavity, a second oil cavity, an air cavity, and a heat exchange fluid cavity. Injecting oil into the first or second oil cavity drives the heat exchange fluid in the heat exchange fluid cavity to move towards or away from the cold-end multi-stage compartment; cold... The multi-stage cooling chamber includes radiators and sequentially connected, S-shaped cold-end heat exchange chambers, cold-end relaxation chambers, and cold-end cold chambers. Radiators are installed on both the upper and lower sides of the cold-end heat exchange chambers, and the hot-end heat exchangers are located in the heat dissipation zone formed between the two hot-end radiators. The regenerator contains a multi-stage pressurized working fluid with a phase change temperature that gradually increases from below room temperature to room temperature. The length of the regenerator is greater than or much greater than its width. After the heat exchange fluid moves back and forth between the regenerator and the cold-end cold chamber multiple times, a stable axial temperature gradient is formed in the regenerator, so that the pressurized working fluids with different phase change temperatures in the regenerator all work in their respective optimal phase change temperature zones, enabling the cold-end cold chamber to reach the target cooling temperature.

[0007] As a preferred technical solution, the cavity includes a first fluid channel and a second fluid channel. The large piston and the small piston are slidably disposed in the first fluid channel and the second fluid channel, respectively. The sealing ring is fixedly disposed in the second fluid channel, and the end face of the sealing ring and the end of the first fluid channel facing the second fluid channel are located in the same vertical plane. The large piston is fixedly connected to the small piston through a connecting rod passing through the sealing ring.

[0008] As a preferred technical solution, the injection booster device also includes a hydraulic station. The first oil outlet and the second oil outlet of the hydraulic station are connected to the first oil inlet and the second oil inlet of the syringe through a hydraulic oil injection pipe and a hydraulic pressurization pipe, respectively. The first oil inlet and the second oil inlet are connected to the first oil chamber and the second oil chamber, respectively.

[0009] As a preferred technical solution, a limiting baffle is fixedly connected to the inner wall of the cavity, the limiting baffle is located inside the air cavity, and the syringe has an air hole communicating with the air cavity.

[0010] As a preferred technical solution, there are two cold-end heat exchange chambers, and the cold-end heat exchange chamber, the cold-end relaxation chamber, and the cold-end cold chamber are all multi-stage spiral pipes.

[0011] As a preferred technical solution, the cold end relaxation chamber and the outer wall of the cold end cold chamber are covered with insulation cotton, and thermometers are installed on the outer walls of the cold end heat exchange chamber, the cold end relaxation chamber, and the cold end cold chamber.

[0012] As a preferred technical solution, the diameter of the first fluid channel is larger than the diameter of the second fluid channel.

[0013] As a preferred technical solution, the end of the cold end heat exchange chamber connected to the syringe is provided with a cold end heat exchange chamber inlet / outlet pipe, and the end of the cold end cold chamber connected to the regenerator is provided with a cold end cold chamber inlet / outlet pipe.

[0014] As a preferred technical solution, the regenerator includes a detachable fixed end cap and a pressure-resistant shell. A regenerator sealing ring is provided in the connection surface between the end cap and the pressure-resistant shell. A pressure-resistant cavity is formed between the end cap and the pressure-resistant shell. Multiple layers of partitions are detachably connected in the pressure-resistant cavity, and a pressure-locking working fluid is provided between adjacent partitions.

[0015] A pressure-clamping refrigeration method uses a pressure-clamping refrigeration system to inject oil into the first or second oil chamber, causing the heat exchange fluid to move back and forth multiple times between the regenerator and the cold end cold chamber. This ensures that the pressure-clamping working fluids with different phase change temperatures in the regenerator all operate in their respective optimal phase change temperature zones, thereby enabling the cold end cold chamber to reach the target refrigeration temperature.

[0016] The beneficial effects of this invention are as follows:

[0017] (1) In this invention, a single refrigeration loop is formed by sequentially connecting the injection pressurization device, the cold end multi-stage chamber, the regenerator, the high-pressure ball valve, the check valve, and the hot end heat exchanger. Compared with the existing double-loop design and the design of multiple valves on the double loop, the structure is simple, easy to miniaturize, and the cost is reduced. The cold end heat exchange chamber, the cold end relaxation chamber, and the cold end cold chamber are sequentially connected and arranged in an S-shape, which can suppress the thermal disturbance of the pressure system on the cold end. By arranging a multi-stage pressurizing working fluid with a phase change temperature that gradually increases from below room temperature to room temperature in the regenerator, a stable axial temperature gradient can be formed after multiple cycles, so that the pressurizing working fluids with different phase change temperatures in the regenerator all work in their respective optimal phase change temperature zones, so that the cold end cold chamber reaches the target refrigeration temperature. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the card-pressing refrigeration system provided in Embodiment 1 of the present invention;

[0019] Figure 2 This is a schematic diagram of the injection pressurization device provided in Embodiment 1 of the present invention;

[0020] Figure 3 This is a schematic diagram of the cold-end multi-level warehouse structure provided in Embodiment 1 of the present invention;

[0021] Figure 4 This is a partial cross-sectional structural diagram of the regenerator provided in Embodiment 1 of the present invention;

[0022] Figure 5 This is a simulation result diagram of the maximum temperature span between the hot and cold ends in the pressure-cooling refrigeration system provided in Embodiment 1 of the present invention;

[0023] Icon labels:

[0024] 1. Injection pressurization device; 101. Hydraulic station pressure gauge; 102. Hydraulic pressurization pipe; 103. Hydraulic oil injection pipe; 104. Large piston; 105. Small piston; 106. Pressure probe; 107. Sealing ring; 108. Air vent; 109. Fluid pressurization pipe; 110. Limiting baffle; 111. Injector; 112. Hydraulic station; 113. Connecting rod;

[0025] 2. Cold end multi-stage compartment; 201. Cold end heat exchange compartment inlet / outlet pipe; 202. Fan; 203. Cold end heat exchange compartment; 204. Cold end relaxation compartment; 205. Cold end cold compartment; 206. Cold end cold compartment inlet / outlet pipe; 207. Insulation cotton;

[0026] 3. Regenerator; 301. End cap; 302. Pressure-resistant shell; 4. High-pressure ball valve; 5. Check valve; 6. Hot end heat exchanger. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] Example 1

[0029] See Figure 1 A pressure-controlled refrigeration system includes an injection pressurization device 1, a cold-end multi-stage compartment 2, a regenerator 3, a high-pressure ball valve 4, a check valve 5, and a hot-end heat exchanger 6. The injection pressurization device 1, the cold-end multi-stage compartment 2, the regenerator 3, the high-pressure ball valve 4, the check valve 5, and the hot-end heat exchanger 6 are connected in sequence through pipelines to form a closed refrigeration single loop.

[0030] See Figure 2 The injection pressurization device 1 is used to provide the pressure required for the phase change of the pressurizing working fluid, thereby driving the pressurizing working fluid to absorb or release heat; the injection pressurization device 1 includes a hydraulic station 112 and a syringe 111. The hydraulic station 112 is connected to the syringe 111 through a hydraulic oil injection pipe 103 and a hydraulic pressure pipe 102, respectively. The hydraulic pressure pipe 102 is used for pressurizing the refrigeration circuit, and the hydraulic oil injection pipe 103 is used for retraction and reset of the refrigeration circuit;

[0031] One end of the hydraulic injection pipe 103 is connected to the first oil outlet on the hydraulic station 112, and the other end of the hydraulic injection pipe 103 is connected to the first oil injection port at the end of the syringe 111. One end of the hydraulic pressure pipe 102 is connected to the second oil outlet on the hydraulic station 112, and the other end of the hydraulic pressure pipe 102 is connected to the second oil injection port of the syringe 111. A sealed cavity structure is provided inside the syringe 111, and both the first oil injection port and the second oil injection port are connected to the sealed cavity.

[0032] Inside the syringe 111, along the length of the syringe 111, there are sequentially arranged a large piston 104, a sealing ring 107, a limiting baffle 110, and a small piston 105. In this embodiment, the large piston 104, the sealing ring 107, the limiting baffle 110, and the small piston 105 are arranged in the axial direction of the syringe 111, but it is not limited to this.

[0033] The syringe 111 has a first fluid channel and a second fluid channel. The diameter of the first fluid channel is larger than the diameter of the second fluid channel. A large piston 104 is slidably disposed in the first fluid channel. A sealing ring 107 is fixedly disposed in the second fluid channel, and the left end face of the sealing ring 107 is located in the same vertical plane as the end of the first fluid channel facing the second fluid channel. A small piston 105 is slidably disposed in the second fluid channel. A limiting baffle 110 is fixedly connected in the second fluid channel and is used to limit the movement of the small piston 105. In this embodiment, the limiting baffle 110 is located inside the air cavity and is arranged in a ring shape, allowing the connecting rod 113 to pass through, preventing the small piston 105 from moving to the sealing ring 107 and impacting the sealing ring 107. The large piston 104 is fixedly connected to the small piston 105 through the connecting rod 113. The connecting rod 113 passes through the sealing ring 107, and the sealing ring 107 has a through hole adapted to the connecting rod 113. The connecting rod 113 is made of high-pressure resistant stainless steel and is used to enable the large piston 104 and the small piston 105 to move synchronously.

[0034] In this embodiment, the large piston 104, the sealing ring 107, and the small piston 105 divide the cavity of the syringe 111 into a first oil cavity, a second oil cavity, an air cavity, and a heat exchange fluid cavity. Specifically, the sealing ring 107 forms a large cavity for the first fluid channel and a small cavity for the second fluid channel. The large piston 104 divides the large cavity into the first oil cavity and the second oil cavity, and the small piston 105 divides the small cavity into the air cavity and the heat exchange fluid cavity.

[0035] It should be noted that both the first and second oil chambers are filled with anti-wear hydraulic oil. The syringe 111 is provided with an air hole 108 that communicates with the air chamber. Air in the air chamber enters and exits through the air hole 108 to meet the movement requirements of the large piston 104 and the small piston 105. The heat exchange fluid chamber is filled with heat exchange fluid.

[0036] The first oil inlet is connected to the first oil chamber, and the second oil inlet is connected to the second oil chamber. A valve is also provided on the hydraulic oil inlet pipe 103. A hydraulic pressure gauge 101 is provided on the hydraulic station 112. A fluid pressurization pipe 109 is provided at the end of the syringe 111 away from the first oil inlet. A pressure detection needle 106 is provided on the syringe 111. The detection end of the pressure detection needle 106 extends into the heat exchange fluid chamber and is located on the side close to the fluid pressurization pipe 109. The pressure detection needle 106 is used to monitor the pressure value of the heat exchange fluid chamber in real time.

[0037] See Figure 3 The cold end multi-stage chamber 2 includes a cold end heat exchange chamber 203, a cold end relaxation chamber 204, and a cold end cold chamber 205 that are connected in sequence and arranged in an S-shape. In this embodiment, there are two cold end heat exchange chambers 203. The purpose of setting up the cold end heat exchange chamber 203 and the cold end relaxation chamber 204 is to reduce the thermal disturbance of the hot end, i.e., the heat exchange fluid, to the cold end, i.e., the cold end cold chamber 205.

[0038] The cold-end heat exchange chamber 203, cold-end relaxation chamber 204, and cold-end cold chamber 205 are all multi-stage spiral pipes made of high-pressure resistant stainless steel. Both the cold-end relaxation chamber 204 and the cold-end cold chamber 205 are covered with insulation cotton 207 to reduce cold loss. The cold-end heat exchange chamber 203 is closer to the injection pressurization device 1, and the cold-end cold chamber 205 is closer to the regenerator 3. The cold-end relaxation chamber 204 is located between the two to separate the temperature zones. Fans 202 are installed on both the upper and lower sides of the cold-end heat exchange chamber 203 to cool the heat exchange fluid entering the cold-end heat exchange chamber 203. At room temperature, the heat exchange fluid flows sequentially through the cold end heat exchange chamber 203, the cold end relaxation chamber 204, and the cold end cold chamber 205 along the spiral pipe. Thermometers are attached to the outer walls of the spiral pipes of the cold end heat exchange chamber 203, the cold end relaxation chamber 204, and the cold end cold chamber 205 to detect the temperature change of the heat exchange fluid in the pipes in real time. The end of the cold end heat exchange chamber 203 is connected to the fluid pressurization pipe 109 through the cold end heat exchange chamber inlet / outlet pipe 201. The end of the cold end cold chamber 205 is provided with a cold end cold chamber inlet / outlet pipe 206 and is connected to the regenerator 3 through the cold end cold chamber inlet / outlet pipe 206.

[0039] See Figure 4 The regenerator 3 includes an end cap 301 and a pressure-resistant shell 302. The end cap 301 and the pressure-resistant shell 302 are detachably connected. In this embodiment, the end cap 301 is detachably fixed to the pressure-resistant shell 302 by bolts, and a regenerator sealing ring is provided in the connection surface between the end cap 301 and the pressure-resistant shell 302, and is sealed by the regenerator sealing ring. The end cap 301 and the pressure-resistant shell 302 enclose a pressure-resistant cavity. Multiple layers of partitions are detachably connected in the pressure-resistant cavity. The partitions are arranged along the axial direction of the regenerator 3. A pressure-locking working fluid is provided between adjacent partitions. The pressure-locking working fluid in the regenerator 3 has different phase change temperatures. In this embodiment, the pressure-locking working fluid in the regenerator 3 is arranged in a multi-level gradient according to the difference in phase change temperature. The side near the cold end multi-level chamber 2 is filled with a pressure-locking working fluid with a phase change temperature slightly lower than room temperature, and the side near the hot end heat exchanger 6 is filled with a pressure-locking working fluid with a phase change temperature of room temperature.

[0040] See Figure 1 The regenerator 3 is connected to the hot end heat exchanger 6 through a connecting pipe. The hot end heat exchanger 6 is located in the heat dissipation area formed by the upper fan 202 and the lower fan 202. It shares a heat exchange system with the cold end heat exchange chamber 203. After the high temperature heat exchange fluid is pressurized and absorbs heat, it enters the hot end heat exchanger 6 and is cooled to room temperature by the forced heat exchange of the fan 202, thus completing the heat dissipation of the entire system.

[0041] The aspect ratio of the regenerator 3 has a significant impact on the establishment of the temperature gradient within the regenerator 3. In existing pressurized refrigeration systems, the regenerator 3 is basically "tall and thin," which is not conducive to establishing an effective and stable large temperature span in the fluid flow direction. If a temperature span can be achieved, it can only be a small temperature span. If materials with different phase change temperatures are placed in the regenerator 3, the establishment of a small temperature span can only be achieved after multiple cycles when pressurized working fluids with "similar" phase change temperatures work together. This is unfavorable for the generated temperature span, and the generated temperature span is limited. Furthermore, existing technologies all use multi-loop designs, such as hot end outlet and hot end inlet being different inlets and outlets, which is very unfavorable for the establishment of the temperature span within the regenerator 3, and can even be said to directly destroy the temperature span.

[0042] Meanwhile, the regenerator 3 in this embodiment is designed in a "short and long" shape and uses a single loop. Here, "short and long" means that the length of the regenerator 3 is greater than or much greater than its width. In the direction of fluid flow, a temperature span with a large temperature difference between the hot and cold ends will be established in the regenerator 3. Placing a pressure-locking working fluid with a large phase change temperature difference in the regenerator 3 can ensure that the pressure-locking working fluid at each point produces the optimal pressure-locking effect. Furthermore, the single-loop design can very stably maintain the temperature span without being destroyed, which is conducive to achieving a huge temperature drop and thus reaching the target temperature.

[0043] It should be noted that the pressing working medium in this embodiment is a solid pressing working medium, which is a composite material of n-alkane and carbon foam, such as paraffin-based carbon foam composite phase change energy storage material. The phase change temperature of n-alkane varies depending on the number of carbon atoms. In this embodiment, n-octadecane, n-heptadecane, n-hexadecane, n-pentadecanane, and n-tetradecane are used. The phase change temperature of n-octadecane is room temperature, while the phase change temperatures of n-heptadecane, n-hexadecane, n-pentadecanane, and n-tetradecane are lower than room temperature. For example, n-octadecane can be called paraffin-18@carbon foam composite material or carbon foam-supported paraffin-18 composite material, both of which are existing technologies.

[0044] In this embodiment, the working temperature of the pressure-pressing working fluid is at or slightly below room temperature, the driving pressure of the system is 0.1MPa~100MPa, and water is selected as the heat exchange fluid. The multi-stage spiral pipe of the cold end multi-stage chamber 2 and the cavity of the regenerator 3 are made of high-pressure resistant stainless steel to ensure the pressure resistance and sealing stability of the system.

[0045] See Figure 5 Simulation results show that the pressure-cooling system in this embodiment can achieve a maximum temperature range of 26.3K between the hot and cold ends after continuous circulation, demonstrating good cooling temperature range performance.

[0046] It should be noted that the large temperature span is due to two factors: firstly, the pressure-pressing working fluid absorbs heat from the environment, and secondly, the temperature difference between the pressure-pressing working fluid and the environment causes the working fluid to continue absorbing heat. For example, if the water initially propelling the regenerator 3 is at room temperature, ideally, after the material has undergone the previous cycle, its temperature drops to room temperature. Let room temperature be the first temperature. After depressurization, the material will drop from the first temperature to the second temperature. The material at the second temperature will continue to exchange heat with the heat exchange fluid at the first temperature. At this time, the temperature of the heat exchange fluid will drop further. Meanwhile, after multiple cycles, a stable axial temperature gradient is formed in the regenerator 3. This temperature gradient causes the pressure-pressing working fluids at different phase change temperatures in the regenerator 3 to operate in their respective optimal phase change temperature zones, continuously generating the optimal pressure-pressing effect. Ultimately, this achieves a continuous temperature drop at the cold end cold chamber 205 until the target cooling temperature is reached.

[0047] Installation sequence: Completely fill the hydraulic oil injection pipe 103 and hydraulic pressure pipe 102 with anti-wear hydraulic oil, and also fill the first and second oil chambers with anti-wear hydraulic oil; the air cavity between the rubber sealing ring 107 and the small piston 105 is initially filled with air through the air hole 108; completely fill the heat exchange fluid cavity on the side of the small piston 105 near the fluid pressure pipe 109, the fluid pressure pipe 109, the cold end heat exchange chamber inlet / outlet pipe 201, the cold end multi-stage chamber 2, and all connecting pipes with heat exchange fluid; fill the regenerator 3 with pressure-clamping working fluid in a gradient: fill the end of the cold end cold chamber inlet / outlet pipe 206 near the cold end multi-stage chamber 2 with pressure-clamping working fluid with a phase change temperature slightly lower than room temperature, and fill the end near the hot end heat exchanger 6 with pressure-clamping working fluid with a phase change temperature of room temperature; the pores in the regenerator 3, except for the pressure-clamping working fluid, are also filled with heat exchange fluid water to ensure effective transfer of pressure and heat.

[0048] The refrigeration method includes the following steps:

[0049] S1, pressurized phase transition;

[0050] Close the high-pressure ball valve 4, inject anti-wear hydraulic oil into the first oil chamber through the hydraulic pressurization pipe 102, apply pressure to the large piston 104, and drive the small piston 105 to move synchronously towards the cold end multi-stage chamber 2, pressurizing the water in the heat exchange fluid chamber; monitor the pressure in the chamber in real time through the pressure probe 106 until the pressure reaches the set value; at this time, the pressurized working fluid at the end of the regenerator 3 near the hot end heat exchanger 6 undergoes a solid-liquid phase change, releasing phase change heat, which raises the temperature of the heat exchange fluid in the regenerator 3; the pressurized working fluid at the end of the regenerator 3 near the cold end multi-stage chamber 2 does not reach the phase change pressure, only undergoes liquid compression, and there is no obvious release of phase change heat.

[0051] S2, fluid delivery and heat exchange;

[0052] Maintain the above pressurization pressure for a period of time. After the heat exchange fluid in the regenerator 3 has fully absorbed heat, reduce the working fluid temperature to the set value and open the high-pressure ball valve 4. The large piston 104 and the small piston 105 continue to move under the action of hydraulic pressure, pushing all the heat exchange fluid in the heat exchange fluid cavity of the small piston 105 into the cold end heat exchange chamber 203 through the cold end heat exchange chamber inlet and outlet pipe 201. Forced heat exchange is achieved through the fans 202 on the upper and lower sides of the cold end heat exchange chamber 203, which quickly cools the heat exchange fluid entering the cold end heat exchange chamber 203 to room temperature, thereby avoiding heat from affecting the downstream.

[0053] Meanwhile, the heat exchange fluid in the cold end cold chamber 205 enters the regenerator 3 through the cold end cold chamber inlet / outlet pipe 206, and exchanges heat with the pressurized working fluid in the regenerator 3. The high-temperature heat exchange fluid in the regenerator 3, which originally absorbed heat fully, flows through the high-pressure ball valve 4 and check valve 5 after being opened under the thrust of the large piston 104 and the small piston 105. Under the pressure-maintaining action of the check valve 5, the system pressure during this flow process is consistent with the pressure measured by the pressure probe 106 during the pressurization stage. The high-temperature heat exchange fluid finally enters the hot end heat exchanger 6 and is cooled to room temperature by the forced heat exchange of the fan 202, thus completing the heat dissipation of the system.

[0054] S3, generation of cooling capacity due to pressure relief;

[0055] After the heat exchange fluid in the heat exchange fluid chamber of the small piston 105 is pushed to the limited position on the right side of the syringe 111 and pushed into the cold end heat exchange chamber 203 through the fluid pressurization tube 109, the refrigeration circuit is depressurized. In this embodiment, the thrust of the hydraulic pressurization tube 102 is stopped to depressurize.

[0056] After depressurization, the working fluid near the hot end of the heat exchanger 6 in the regenerator 3 undergoes a liquid-solid phase change and its temperature drops rapidly. It then exchanges heat with the heat exchange fluid in the regenerator 3 through contact. The working fluid absorbs heat and its temperature rises, while the heat exchange fluid releases heat and its temperature drops significantly, thus completing the generation of cold energy.

[0057] S4, Fluid retraction and circuit reset;

[0058] After maintaining the depressurized state for a period of time, and after the heat exchange fluid in the regenerator 3 has been fully cooled, oil is injected into the large cavity through the hydraulic oil injection pipe 103, which drives the large piston 104 and the small piston 105 to move synchronously away from the cold end multi-stage chamber 2, thereby realizing the system's back-pull-back reset.

[0059] During this process, the heat exchange fluid that was originally pushed into the cold end heat exchange chamber 203 is drawn back into the heat exchange fluid cavity through the cold end heat exchange chamber inlet / outlet pipe 201 and the fluid pressurization pipe 109; the low-temperature heat exchange fluid that has been cooled in the regenerator 3 enters the cold end cold chamber 205 through the cold end cold chamber inlet / outlet pipe 206, realizing the transfer of cold energy to the cold end; the heat exchange fluid that has been cooled to room temperature in the hot end heat exchanger 6 enters the regenerator 3 to fill the flow channel gap; until the large piston 104 and the small piston 105 have completely returned to their initial positions before pressurization, the back-drawing operation stops, and the high-pressure ball valve 4 is closed, completing one complete refrigeration cycle;

[0060] S5, continuous cycle and low-temperature refrigeration;

[0061] Repeat the above operations of pressurization phase change, fluid push and heat exchange, depressurization cold generation, fluid return and loop reset to perform multiple refrigeration cycles; as the number of cycles increases, a stable axial temperature gradient gradually forms inside the regenerator 3: the temperature on the side near the cold end multi-stage chamber 2 remains below room temperature, while the temperature on the side near the hot end heat exchanger 6 remains at room temperature.

[0062] This temperature gradient causes the pressurizing working fluids with different phase change temperatures in the regenerator 3 to operate in their respective optimal phase change temperature zones, continuously generating the optimal pressurizing effect, and ultimately achieving a continuous temperature drop at the cold end cold chamber 205 until the target refrigeration temperature is reached.

[0063] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A pressure-cooling system, characterized in that, The system includes, in sequence, an injection pressurization device, a cold-end multi-stage chamber, a regenerator, a high-pressure ball valve, a check valve, and a hot-end heat exchanger. The injection pressurization device includes a syringe with a sealed cavity structure containing a large piston and a small piston capable of synchronous reciprocating movement. A sealing ring is fixed within the cavity. The large piston, sealing ring, and small piston divide the cavity into a first oil chamber, a second oil chamber, an air chamber, and a heat exchange fluid chamber. Injecting oil into the first or second oil chamber drives the heat exchange fluid in the heat exchange fluid chamber to move towards or away from the cold-end multi-stage chamber. The cold-end multi-stage chamber includes a radiator and, in sequence, a... The cold-end heat exchange chamber, cold-end relaxation chamber, and cold-end cold chamber are arranged in an S-shape. Radiators are provided on both the upper and lower sides of the cold-end heat exchange chamber, and the hot-end heat exchanger is located in the heat dissipation zone formed between the two hot-end radiators. The regenerator contains a multi-stage pressurized working fluid with a phase change temperature that gradually increases from below room temperature to room temperature. The length of the regenerator is greater than or much greater than its width. After the heat exchange fluid moves back and forth between the regenerator and the cold-end cold chamber multiple times, a stable axial temperature gradient is formed in the regenerator. This ensures that the pressurized working fluids with different phase change temperatures in the regenerator all work in their respective optimal phase change temperature zones, allowing the cold-end cold chamber to reach the target cooling temperature.

2. The pressure-cooling system according to claim 1, characterized in that, The cavity includes a first fluid channel and a second fluid channel. A large piston and a small piston are slidably disposed in the first fluid channel and the second fluid channel, respectively. A sealing ring is fixedly disposed in the second fluid channel, and the end face of the sealing ring and the end of the first fluid channel facing the second fluid channel are located in the same vertical plane. The large piston is fixedly connected to the small piston through a connecting rod passing through the sealing ring.

3. The pressure-cooling system according to claim 1, characterized in that, The injection booster device also includes a hydraulic station. The first oil outlet and the second oil outlet of the hydraulic station are connected to the first oil inlet and the second oil inlet of the syringe through a hydraulic oil injection pipe and a hydraulic pressurization pipe, respectively. The first oil inlet and the second oil inlet are connected to the first oil chamber and the second oil chamber, respectively.

4. The pressure-cooling system according to claim 1, characterized in that, A limiting baffle is fixedly connected to the inner wall of the cavity. The limiting baffle is located inside the air cavity, and the syringe has an air hole that communicates with the air cavity.

5. The pressure-cooling system according to claim 1, characterized in that, There are two cold-end heat exchange chambers. The cold-end heat exchange chamber, the cold-end relaxation chamber, and the cold-end cold chamber are all multi-stage spiral pipes.

6. The pressure-cooling system according to claim 1, characterized in that, The cold end relaxation chamber and the cold end cold chamber are all covered with insulation cotton, and thermometers are installed on the outer walls of the cold end heat exchange chamber, the cold end relaxation chamber, and the cold end cold chamber.

7. The pressure-cooling system according to claim 1, characterized in that, The diameter of the first fluid channel is larger than the diameter of the second fluid channel.

8. The pressure-cooling system according to claim 1, characterized in that, The end of the cold end heat exchange chamber connected to the syringe is equipped with a cold end heat exchange chamber inlet / outlet pipe, and the end of the cold end cold chamber connected to the regenerator is equipped with a cold end cold chamber inlet / outlet pipe.

9. A pressure-cooling system according to claim 1, characterized in that, The regenerator includes a detachable fixed end cap and a pressure-resistant shell. A regenerator sealing ring is provided in the connection surface between the end cap and the pressure-resistant shell. The end cap and the pressure-resistant shell enclose a pressure-resistant cavity. Multiple layers of partitions are detachably connected in the pressure-resistant cavity, and a pressure-locking working fluid is provided between adjacent partitions.

10. A compression-cooling method, characterized in that, Using the compression refrigeration system as described in any one of claims 1-9, oil is injected into the first or second oil chamber to cause the heat exchange fluid to move back and forth multiple times between the regenerator and the cold end cold chamber, so that the compression working fluids with different phase change temperatures in the regenerator all work in their respective optimal phase change temperature zones, and the cold end cold chamber reaches the target refrigeration temperature.

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