Pump-driven cold fluid refrigerating system

Abstract

The invention discloses a pump-driven cold fluid refrigerating system, and belongs to the technical field of refrigerator refrigeration, the pump-driven cold fluid refrigerating system comprises a heat preservation box body, a Stirling cryocooler and a low-temperature pumping mechanism, the heat preservation box body comprises an inner container, a transmission pipeline and a low-temperature heat insulation layer, the transmission pipeline is arranged between the inner container and the heat preservation box body, and the transmission pipeline is connected with the Stirling cryocooler; a low-temperature transportation working medium is arranged in the transmission pipeline; the Stirling cryocooler comprises a cryocooler main body and a cold finger connected to the cryocooler main body, and the cold finger is used for exchanging heat with the low-temperature transportation working medium; the low-temperature pumping mechanism comprises a pump body and a driving part connected to the pump body, an inlet and an outlet of the driving part are connected to an outlet and an inlet of the conveying pipeline respectively, or the driving part is located in the conveying pipeline. The low-temperature transportation working medium can be transported to all parts of the heat preservation box body, so that the more efficient and more uniform refrigeration effect is achieved, and the requirement for long-term and stable storage of various materials in the space environment is met.

Description

Technical Field

[0001] The invention relates to the technical field of refrigerator refrigeration, and in particular to a pump-driven cold fluid refrigeration system. Background Art

[0002] As aerospace technology advances with each passing day, space refrigerators are becoming increasingly important as key equipment for maintaining the quality of important materials in spacecraft, the International Space Station, and deep space probes. Space refrigerators are specially designed for use in the extreme and special environment of space, aiming to provide stable low-temperature storage conditions to ensure the safety and effectiveness of food, medicines, and other sensitive items during long-distance space travel.

[0003] Space refrigerators are widely used in various space missions and have become an indispensable part of supporting long-term space residence and exploration. They not only meet the basic living needs of astronauts and ensure the freshness and safety of food, but also bear the important responsibility of preserving key medicines and scientific samples. They play a vital role in maintaining the health of astronauts and supporting scientific experiments and data collection.

[0004] However, compared with ground refrigeration systems, the design and operation of space refrigerators face completely different technical challenges, which are mainly due to the uniqueness of the space environment: Microgravity environment: Under microgravity conditions, the traditional convection heat dissipation mechanism fails, resulting in reduced heat transfer efficiency and increased refrigeration difficulty. At the same time, the distribution and management of liquid working fluids has also become a major problem, requiring innovative technical solutions to ensure the effective circulation and utilization of refrigerants.

[0005] Vacuum state: The vacuum environment in space means there is no medium for natural convection and conduction heat dissipation, which places extremely high demands on the insulation materials and sealing performance of the refrigerator to prevent heat from being lost quickly through radiation, while also increasing the complexity of thermal management.

[0006] Radiation environment: Cosmic rays and high-energy particles pose a potential threat to electronic equipment and materials of refrigeration systems, which may cause performance degradation or even failure. Therefore, space refrigerators must use radiation-resistant materials and designs to ensure long-term stable operation.

[0007] Although the existing space refrigerator technology has made significant progress, there are still deficiencies in refrigeration uniformity. In the space environment, uneven refrigeration may cause the local temperature of the stored items to be too high or too low, affecting the preservation effect. This problem is particularly critical for medicines and scientific samples that require precise temperature control. Therefore, the development of a space refrigerator technology that can effectively improve refrigeration uniformity has become an important issue that needs to be solved in the current aerospace science and technology field. Summary of the invention

[0008] The purpose of the present invention is to provide a pump-driven cold fluid refrigeration system to solve the problems existing in the above-mentioned prior art. A Stirling refrigerator is used to provide cooling capacity for the low-temperature transport working fluid, and a low-temperature pumping mechanism is used to provide flow power for the low-temperature transport working fluid, so that the low-temperature transport working fluid can be transported to various parts of the insulation box, thereby achieving a more efficient and uniform refrigeration effect, and meeting the needs of long-term and stable storage of various materials in the space environment.

[0009] To achieve the above object, the present invention provides the following solutions: The present invention provides a pump-driven cold fluid refrigeration system, comprising a heat preservation box, a Stirling refrigerator and a low-temperature pumping mechanism, wherein the heat preservation box comprises an inner liner, a transmission pipeline and a low-temperature insulation layer, the transmission pipeline is arranged between the inner liner and the heat preservation box, and a low-temperature transport working medium is arranged in the transmission pipeline; the Stirling refrigerator comprises a refrigerator body and a cold finger connected to the refrigerator body, and the cold finger is used for heat exchange with the low-temperature transport working medium; the low-temperature pumping mechanism comprises a pump body and a driving part connected to the pump body, the inlet and outlet of the driving part are respectively connected to the outlet and inlet of the transmission pipeline, or the driving part is located in the transmission pipeline.

[0010] In one embodiment, the driving part is located in the transmission pipeline, and the driving part includes a driving chamber and a one-way inlet valve and a one-way outlet valve connected to the driving chamber, the one-way inlet valve faces the incoming flow direction, and the one-way outlet valve faces the outgoing flow direction.

[0011] In one embodiment, the pump body includes a piston cylinder, a moving piston located in the piston cylinder, and a motor assembly driving the moving piston to reciprocate, the piston cylinder is connected to the driving chamber, and the moving piston is used to move toward or away from the driving chamber.

[0012] In one embodiment, the motor assembly includes a housing, and a mover and a stator located in the housing, and the mover is supported in the housing by a leaf spring.

[0013] In one embodiment, the cold finger is located downstream of the driving part and close to the one-way outlet valve.

[0014] In one embodiment, the cold head in the cold finger is filled with a porous medium, one side of the porous medium exchanges heat with the low-temperature transport medium, and the other side of the porous medium exchanges heat with the expansion chamber.

[0015] In one embodiment, the refrigerator body includes a linear compressor and a phase adjustment mechanism, the linear compressors are arranged oppositely on two sides of the phase adjustment mechanism, and the axial direction of the cold finger is perpendicular to the axial direction of the linear compressor.

[0016] In one embodiment, the transmission pipeline is distributed on the outer wall of the inner pot, and a storage space is formed inside the inner pot. The storage space is divided into a plurality of storage chambers, and the inner pot adopts a uniform temperature heat plate or a metal entity.

[0017] In one embodiment, the transmission pipeline is an annealed stainless steel pipeline, and the low-temperature transport medium is helium.

[0018] In one embodiment, the low-temperature insulation layer surrounds the transmission pipeline, and the material used for the low-temperature insulation layer includes polyurethane foam, perlite, glass wool or vacuum insulation layer.

[0019] Compared with the prior art, the present invention has achieved the following technical effects: The present invention utilizes a Stirling refrigerator to provide cooling capacity for a cryogenic transport medium, and utilizes a cryogenic pumping mechanism to provide flow power for the cryogenic transport medium, so that the cryogenic transport medium can be transported to various parts of a heat preservation box in a transmission pipeline, and the cooling capacity is transferred to the inner liner through the transmission pipeline, so that the temperature of the inner liner and its interior can be reduced, and the inner liner can be used as a cabin for low-temperature storage. Through the active transportation of the cryogenic transport medium, the influence of the microgravity environment on the cryogenic transport medium is avoided, thereby achieving a more efficient and uniform refrigeration effect, and meeting the needs of long-term and stable storage of various materials in a space environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 It is a layout diagram of a pump-driven cooling fluid refrigeration system in an embodiment of the present invention; Among them, 1. Stirling refrigerator; 2. Low temperature pumping mechanism; 3. Insulation box; 11. Cold finger; 12. Linear compressor; 13. Phase adjustment mechanism; 21. One-way outlet valve; 22. Moving piston; 23. Motor assembly; 24. Leaf spring; 25. Piston cylinder; 26. One-way inlet valve; 31. Inner tank; 32. Transmission pipeline; 33. Low-temperature insulation layer. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] The purpose of the present invention is to provide a pump-driven cold fluid refrigeration system to solve the problems existing in the prior art. A Stirling refrigerator is used to provide cooling capacity for a low-temperature transport working fluid, and a low-temperature pumping mechanism is used to provide flow power for the low-temperature transport working fluid, so that the low-temperature transport working fluid can be transported to various parts of an insulated box, thereby achieving a more efficient and uniform refrigeration effect and meeting the needs of long-term and stable storage of various materials in a space environment.

[0024] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0025] Stirling refrigerator (also known as ST refrigerator) is a thermodynamic cycle refrigerator. Stirling refrigerator is a mechanical refrigerator driven by electricity. It is based on the Stirling cycle proposed by Scottish physicist Robert Stirling in 1816, also known as the constant volume regenerative cycle. The reverse cycle of this cycle is called the reverse Stirling cycle, or the Stirling refrigeration cycle when used for refrigeration. Stirling refrigerator uses the expansion and compression of gas at different temperatures to achieve the refrigeration effect. Its working principle is mainly based on the Stirling cycle, which includes four main processes: compression, heating, expansion and cooling. During the compression process, the gas is compressed and heated; during the heating process, the compressed gas enters the high-temperature heat exchanger and absorbs external heat; during the expansion process, the gas enters the expansion piston and expands, converting part of the thermal energy into mechanical energy and cooling at the same time; during the cooling process, the expanded gas enters the low-temperature heat exchanger, contacts with the environment and dissipates heat, further reducing the temperature. These four processes are repeated to continuously produce a refrigeration effect.

[0026] like Figure 1As shown, the present invention provides a pump-driven cold fluid refrigeration system, including an insulation box 3, a Stirling refrigerator 1 and a low-temperature pumping mechanism 2, the insulation box 3 includes an inner liner 31, a transmission pipeline 32 and a low-temperature insulation layer 33, and the transmission pipeline 32 is arranged between the inner liner 31 and the insulation box 3. On the one hand, the transmission pipeline 32 can transfer the low temperature to the inside of the inner liner 31 through the inner liner 31, so that a low-temperature storage environment is formed inside the inner liner 31, and on the other hand, the low-temperature insulation layer 33 can prevent the low temperature from being transmitted to the outside and reduce the low-temperature loss. A low-temperature transport medium is arranged in the transmission pipeline 32, and the low-temperature transport medium can be a gas such as helium, nitrogen or hydrogen. The Stirling refrigerator 1 includes a refrigerator body and a cold finger 11 connected to the refrigerator body. The cold finger 11 is the core part of the Stirling refrigerator 1 responsible for achieving the refrigeration effect. It includes an expansion chamber, an expansion piston, and related heat exchangers (such as a regenerator) and other components. During the operation of the Stirling refrigerator 1, the cold finger 11 transfers heat from the low-temperature area to the high-temperature area through the expansion and cooling process of the gas, thereby achieving the refrigeration effect. By connecting the cold finger 11 to the transmission pipeline 32, the cold finger 11 can be used to exchange heat with the low-temperature transport medium to reduce the temperature of the low-temperature transport medium, that is, the cold capacity of the cold finger 11 is transported by the low-temperature transport medium. The cryogenic pumping mechanism 2 includes a pump body and a driving part connected to the pump body. In one case, the transmission pipeline 32 may be provided with an inlet and an outlet. In this case, the inlet and outlet of the driving part are respectively connected to the outlet and inlet of the transmission pipeline 32. Under the action of the driving part, the cryogenic transport medium in the transmission pipeline 32 enters the inlet of the driving part from the outlet of the transmission pipeline 32, and then enters the inlet of the transmission pipeline 32 from the outlet of the driving part, thereby forming an active flow of the cryogenic transport medium. In another case, the transmission pipeline 32 does not have a clear division, nor a clear inlet and outlet. In this case, the driving part may be located in the transmission pipeline 32, and the cryogenic transport medium is driven to flow in the transmission pipeline 32 by using the one-end-in-one-end-out driving method of the driving part itself.

[0027] The present invention utilizes a Stirling refrigerator 1 to provide cooling capacity for a cryogenic transport medium, and utilizes a cryogenic pumping mechanism 2 to provide flow power for the cryogenic transport medium, so that the cryogenic transport medium can be transported to various parts of a heat preservation box 3 in a transmission pipeline 32, and the cooling capacity is transferred to the inner liner 31 through the transmission pipeline 32, so that the temperature of the inner liner 31 and its interior can be reduced, and the inner liner 31 can be used as a cabin for low-temperature storage. Through the active transportation of the cryogenic transport medium, the influence of the microgravity environment on the cryogenic transport medium is avoided, thereby achieving a more efficient and uniform refrigeration effect, and meeting the needs of long-term and stable storage of various materials in a space environment.

[0028] The present invention is provided with a Stirling refrigerator 1 and a low temperature pumping mechanism 2. The refrigeration capacity can be adjusted by adjusting the Stirling refrigerator 1, and the flow rate can be adjusted by adjusting the low temperature pumping mechanism 2, thereby realizing dual adjustment of temperature zone and cooling capacity.

[0029] In one embodiment, the driving part is located in the transmission pipeline 32, and the driving part includes a driving chamber and a one-way inlet valve 26 and a one-way outlet valve 21 connected to the driving chamber. The one-way inlet valve 26 faces the incoming flow direction, and the low-temperature transport medium can only enter in one direction. The one-way outlet valve 21 faces the outgoing flow direction, and the low-temperature transport medium can only flow out in one direction. Therefore, when the pressure of the driving chamber changes, the one-way inlet valve 26 and the one-way outlet valve 21 cooperate to achieve a one-way flow of the low-temperature transport medium. To achieve the above purpose, the low-temperature pumping mechanism 2 includes but is not limited to a compressor in the form of a piston pump driven by a linear motor, a diaphragm pump, a pump driven by a piezoelectric effect, or a similar form of pump. The form of the one-way inlet valve 26 and the one-way outlet valve 21 includes but is not limited to a flat valve, a reed valve, a ring valve, a mesh valve or a butterfly valve.

[0030] In one embodiment, the pump body includes a piston cylinder 25, a moving piston 22 located in the piston cylinder 25, and a motor assembly 23 that drives the moving piston 22 to reciprocate. The piston cylinder 25 is connected to the driving chamber. Driven by the motor assembly 23, the moving piston 22 moves toward or away from the driving chamber. Therefore, the volume of the piston cylinder 25 is expanded by the moving piston 22, and the overall volume of the piston cylinder 25 and the driving chamber can be expanded, and a negative pressure suction force is formed at the position of the one-way inlet valve 26. The negative pressure suction force is used to inhale the low-temperature transport medium through the one-way inlet valve 26. It should be noted that the one-way outlet valve 21 is in a closed state at this time; the volume of the piston cylinder 25 is compressed by the moving piston 22, and the overall volume of the piston cylinder 25 and the driving chamber can be reduced, and the positive pressure thrust is used to discharge the low-temperature transport medium through the one-way outlet valve 21. It should be noted that the one-way inlet valve 26 is in a closed state at this time. The structure of the moving piston 22 includes but is not limited to a single piston structure and a double piston structure. The former arrangement can reduce the space volume, and the latter arrangement can offset the vibration impact when moving toward or away from each other along the axial direction.

[0031] In one embodiment, the motor assembly 23 includes a housing and a mover and a stator located in the housing. The mover can reciprocate axially relative to the stator. The mover is supported in the housing by a leaf spring 24, and the leaf spring 24 is used to provide axial and radial support for the movement of the mover. The leaf spring 24 can be an Archimedean spiral type, a circular involute type, or an eccentric circular involute type. The leaf spring 24 and the piston cylinder 25 form a gap seal to maintain a dynamic seal between the moving part and the piston cylinder 25 during the movement process, and provide sufficient axial stiffness and radial support for the reciprocating motion of the moving part.

[0032] In one embodiment, the cold finger 11 is located downstream of the driving unit and close to the one-way outlet valve 21. That is to say, the low-temperature transport medium discharged by the driving unit through the one-way outlet valve 21 can reach the position of the cold finger 11 when the kinetic energy is relatively large, thereby improving the passability of the low-temperature transport medium and ensuring that the low-temperature transport medium can smoothly pass through the cold finger 11 and realize circulation flow in the transmission pipeline 32.

[0033] In one embodiment, the cold head in the cold finger 11 is filled with a porous medium, one side of the porous medium exchanges heat with the low-temperature transport medium, and the other side of the porous medium exchanges heat with the expansion chamber. By using a porous medium, the heat exchange efficiency between the cold finger 11 and the low-temperature transport medium in the transmission pipeline 32 can be increased.

[0034] In one embodiment, the refrigerator body includes a linear compressor 12 and a phase adjustment mechanism 13. The linear compressor 12 is arranged oppositely on both sides of the phase adjustment mechanism 13. The linear compressor 12 and the phase adjustment mechanism 13 are coaxially integrated, and the axial direction of the cold finger 11 is perpendicular to the axial direction of the linear compressor 12. The above arrangement makes the structure simple, compact and efficient, and is convenient for coupling with the transmission pipeline 32 in the insulation box 3 and taking cold. The linear compressor 12 includes a compressor piston body, a compressor cylinder body and a long-life leaf spring, etc. The use of a linear motor for driving and an opposed arrangement can reduce the impact of momentum. The linear compressor 12 reciprocates to form a compression chamber and a back pressure chamber to drive the cold finger 11. The phase adjustment mechanism 13 includes a phase adjustment cylinder body, a phase adjustment piston body and a phase adjustment reset elastic element. The efficiency of the refrigerator body is improved by adjusting the phase of the refrigerator body.

[0035] In one embodiment, the transmission pipeline 32 is distributed on the outer wall of the inner liner 31, and the interior of the inner liner 31 forms a storage space. The storage space can be divided into multiple storage rooms as needed, and the outer wall position of the inner liner 31 corresponding to each storage room can be laid with transmission pipelines 32 of different lengths or numbers, so as to obtain storage rooms with different temperatures for storing items with different temperature requirements. The inner liner 31 adopts a uniform temperature hot plate or a metal entity, which can achieve a good temperature transfer effect, effectively ensure that the low temperature of the transmission pipeline 32 is transferred to the inner liner 31, so that the temperature of the pump-driven cold fluid refrigeration system or the refrigerator prepared by it is more uniform, and the refrigeration effect is effectively improved. The metal entity inner liner 31 has the characteristics of good thermal conductivity, wear resistance, and long life.

[0036] In one embodiment, the transmission pipeline 32 is made of annealed stainless steel pipeline, which can be effectively bent multiple times and is convenient for layout and installation. Helium is used as a cryogenic transport medium. As an ideal cryogenic transport medium, helium has the advantages of being green, environmentally friendly, highly efficient, having a large cooling capacity, and being able to achieve rapid refrigeration in deep cryogenic areas. At the same time, helium has stable chemical properties and is not easy to react with other substances, so it has high safety during use. Of course, the transmission pipeline 32 can also include other flexible installation methods to facilitate the realization of the required installation structure and ensure high heat transfer efficiency.

[0037] In one embodiment, the low-temperature insulation layer 33 surrounds the transmission pipeline 32, reduces the cold energy dissipated from the transmission pipeline 32 to the outside, and ensures that the low-temperature transport medium efficiently transfers cold energy to the inner tank 31. The material used for the low-temperature insulation layer 33 includes polyurethane foam, perlite, glass wool or vacuum insulation layer. One of these materials can be used alone, or a combination of multiple materials can be used.

[0038] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A pump-driven cooling fluid refrigeration system, characterized in that: include: A heat preservation box, the heat preservation box comprising an inner liner, a transmission pipeline and a low-temperature insulation layer, the transmission pipeline is arranged between the inner liner and the heat preservation box, and a low-temperature transport medium is arranged in the transmission pipeline; A Stirling refrigerator, the Stirling refrigerator comprising a refrigerator body and a cold finger connected to the refrigerator body, the cold finger being used to exchange heat with the low-temperature transport medium; And a low-temperature pumping mechanism, the low-temperature pumping mechanism includes a pump body and a driving part connected to the pump body, the inlet and outlet of the driving part are respectively connected to the outlet and inlet of the transmission pipeline, or the driving part is located in the transmission pipeline.

2. The pump-driven cooling fluid refrigeration system according to claim 1, characterized in that: The driving part is located in the transmission pipeline, and includes a driving cavity and a one-way inlet valve and a one-way outlet valve connected to the driving cavity. The one-way inlet valve faces the incoming flow direction, and the one-way outlet valve faces the outgoing flow direction.

3. The pump-driven cooling fluid refrigeration system according to claim 2, characterized in that: The pump body comprises a piston cylinder, a moving piston located in the piston cylinder, and a motor assembly driving the moving piston to reciprocate. The piston cylinder is connected to the driving chamber, and the moving piston is used to move toward or away from the driving chamber.

4. The pump-driven cooling fluid refrigeration system according to claim 3, characterized in that: The motor assembly includes a housing, and a mover and a stator located in the housing. The mover is supported in the housing by a leaf spring.

5. The pump-driven cooling fluid refrigeration system according to claim 2, characterized in that: The cold finger is located downstream of the driving part and close to the one-way outlet valve.

6. The pump-driven cooling fluid refrigeration system according to claim 1, characterized in that: The cold head in the cold finger is filled with a porous medium, one side of the porous medium exchanges heat with the low-temperature transport medium, and the other side of the porous medium exchanges heat with the expansion chamber.

7. The pump-driven cooling fluid refrigeration system according to claim 1, characterized in that: The refrigerator body comprises a linear compressor and a phase adjustment mechanism. The linear compressor is arranged oppositely on two sides of the phase adjustment mechanism. The axial direction of the cold finger is perpendicular to the axial direction of the linear compressor.

8. The pump-driven cooling fluid refrigeration system according to claim 1, characterized in that: The transmission pipeline is distributed on the outer wall of the inner pot, and a storage space is formed inside the inner pot. The storage space is divided into a plurality of storage chambers. The inner pot adopts a temperature-averaging hot plate or a metal entity.

9. The pump-driven cooling fluid refrigeration system according to claim 1, characterized in that: The transmission pipeline is made of annealed stainless steel pipeline, and the low-temperature transport working medium is helium.

10. The pump-driven cooling fluid refrigeration system according to claim 1, characterized in that: The low-temperature insulation layer surrounds the transmission pipeline, and the material used for the low-temperature insulation layer includes polyurethane foam, perlite, glass wool or vacuum insulation layer.

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