A pump-driven cold fluid refrigeration system

Abstract

The present invention discloses a pump-driven cold fluid refrigeration system, belonging to the technical field of refrigerator refrigeration, which includes a heat-insulating box body, a Stirling refrigerator and a low-temperature pumping mechanism. The heat-insulating box body includes an inner container, a transmission pipeline and a low-temperature heat-insulating layer. The transmission pipeline is arranged between the inner container and the heat-insulating box body, and a low-temperature transport working medium is arranged in the transmission pipeline. The Stirling refrigerator includes a refrigerator main body and a cold finger connected to the refrigerator main body, and the cold finger is used for heat exchange with the low-temperature transport working medium. 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. The present invention enables the low-temperature transport working medium to be transported to various parts of the heat-insulating box body, thereby achieving a more efficient and more uniform refrigeration effect and meeting the requirements for long-term and stable storage of various materials in the space environment.

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:

[0005] 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.

[0006] 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.

[0007] 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.

[0008] 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

[0009] The object 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. By using a Stirling refrigerator to provide cold energy for the cryogenic transport medium and a cryogenic pumping mechanism to provide the flow power of the cryogenic transport medium, the cryogenic transport medium can be transported to various parts of the insulated box body, so as to achieve a more efficient and uniform refrigeration effect and meet the requirements of long-term and stable storage of various materials in the space environment.

[0010] To achieve the above object, the present invention provides the following solutions:

[0011] The present invention provides a pump-driven cold-fluid refrigeration system, including an insulated box body, a Stirling refrigerator and a cryogenic pumping mechanism. The insulated box body includes an inner container, a transmission pipeline and a cryogenic insulation layer. The transmission pipeline is arranged between the inner container and the insulated box body, and a cryogenic transport medium is arranged in the transmission pipeline. The Stirling refrigerator includes a refrigerator main body and a cold finger connected to the refrigerator main body. The cold finger is used for heat exchange with the cryogenic transport medium. The cryogenic 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.

[0012] In an embodiment, the driving part is located in the transmission pipeline. The driving part includes a driving cavity, 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.

[0013] In an embodiment, the pump body includes a piston cylinder, a moving piston located in the piston cylinder, and a motor assembly for driving the moving piston to reciprocate. The piston cylinder communicates with the driving cavity, and the moving piston is used to move towards or away from the driving cavity.

[0014] In an embodiment, the motor assembly includes a housing, a rotor and a stator located in the housing. The rotor is supported in the housing by a leaf spring.

[0015] In an embodiment, the cold finger is located downstream of the driving part, near the one-way outlet valve.

[0016] In an embodiment, the cold head in the cold finger is filled with a porous medium. One side of the porous medium exchanges heat with the cryogenic transport medium, and the other side of the porous medium exchanges heat with the expansion cavity.

[0017] In an embodiment, the refrigerator main body includes a linear compressor and a phase adjustment mechanism. The linear compressors are arranged oppositely on both sides of the phase adjustment mechanism, and the axis of the cold finger is perpendicular to the axis of the linear compressor.

[0018] In one embodiment, the transmission pipeline is distributed on the outer wall of the inner container, an accommodation space is formed inside the inner container, the accommodation space is divided into a plurality of storage chambers, and the inner container is made of an isothermal heat plate or a metal entity.

[0019] In one embodiment, the transmission pipeline is made of annealed stainless steel pipeline, and the low-temperature transport medium is helium.

[0020] In one embodiment, the low-temperature heat insulation layer surrounds the transmission pipeline, and the materials used for the low-temperature heat insulation layer include polyurethane foam, perlite, glass wool or a vacuum heat insulation layer.

[0021] The present invention has achieved the following technical effects compared with the prior art:

[0022] The present invention uses a Stirling refrigerator to provide cold for the low-temperature transport medium, and uses a low-temperature pumping mechanism to provide the flow power of the low-temperature transport medium, so that the low-temperature transport medium can be transported to various parts of the heat preservation box body in the transmission pipeline, and the cold is transferred to the inner container through the transmission pipeline, which can reduce the temperature of the inner container and its interior, and the inner container can be used as a low-temperature storage cabin. Through the active transportation of the low-temperature transport medium, the influence of the microgravity environment on the low-temperature transport medium is avoided, so that a more efficient and more uniform refrigeration effect can be achieved, and the needs of storing various materials for a long time and stably in the space environment can be met. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0024] Figure 1 It is the layout diagram of the pump-driven cold fluid refrigeration system in the embodiment of the present invention;

[0025] Wherein, 1, Stirling refrigerator; 2, low-temperature pumping mechanism; 3, heat preservation box body;

[0026] 11, cold finger; 12, linear compressor; 13, phase modulation mechanism;

[0027] 21, one-way outlet valve; 22, moving piston; 23, motor assembly; 24, leaf spring; 25, piston cylinder; 26, one-way inlet valve;

[0028] 31, inner container; 32, transmission pipeline; 33, low-temperature heat insulation layer. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0030] The object of the present invention is to provide a pump-driven cold fluid refrigeration system to solve the problems existing in the prior art. The Stirling refrigerator is used to provide cold energy for the low-temperature transport working fluid, and the low-temperature pumping mechanism is used to provide the flow power of the low-temperature transport working fluid, so that the low-temperature transport working fluid can be transported to various parts of the insulated box body, 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.

[0031] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0032] A Stirling refrigerator (also known as an ST cooler) is a thermodynamic cycle refrigerator. The Stirling refrigerator is a mechanical refrigerator driven by electricity. It is based on the Stirling cycle proposed by the 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. The 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 up; during the heating process, the compressed gas enters the high-temperature heat exchanger to absorb 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 down at the same time; during the cooling process, the expanded gas enters the low-temperature heat exchanger, contacts the environment and dissipates heat, further reducing the temperature. These four processes cycle continuously to continuously produce a refrigeration effect.

[0033] As Figure 1As shown in the figure, the present invention provides a pump-driven cold fluid refrigeration system, which includes a heat-insulating box body 3, a Stirling refrigerator 1, and a cryogenic pumping mechanism 2. The heat-insulating box body 3 includes an inner container 31, a transmission pipeline 32, and a cryogenic insulation layer 33. The transmission pipeline 32 is arranged between the inner container 31 and the heat-insulating box body 3. On the one hand, the transmission pipeline 32 can transfer the low temperature to the inside of the inner container 31 through the inner container 31, so that a low-temperature storage environment is formed inside the inner container 31. On the other hand, the cryogenic insulation layer 33 can prevent the low temperature from being transferred to the outside and reduce the low-temperature loss. A cryogenic transport working fluid is arranged in the transmission pipeline 32, and the cryogenic transport working fluid can adopt gases such as helium, nitrogen, or hydrogen. The Stirling refrigerator 1 includes a refrigerator main body and a cold finger 11 connected to the refrigerator main body. The cold finger 11 is the core part of the Stirling refrigerator 1 responsible for achieving the refrigeration effect. It includes an expansion cavity, 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 region to the high-temperature region 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, heat exchange can be carried out between the cold finger 11 and the cryogenic transport working fluid to reduce the temperature of the cryogenic transport working fluid, that is, the cold quantity of the cold finger 11 is transported by the cryogenic transport working fluid. 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 can be provided with an inlet and an outlet. At this time, 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 working fluid 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, forming an active flow of the cryogenic transport working fluid. In another case, the transmission pipeline 32 does not have a clear break and does not have a clear inlet and outlet. At this time, the driving part can be located in the transmission pipeline 32, and the driving method of one end in and one end out of the driving part itself is used to drive the cryogenic transport working fluid to flow in the transmission pipeline 32.

[0034] The present invention uses the Stirling refrigerator 1 to provide cold quantity for the cryogenic transport working fluid, and uses the cryogenic pumping mechanism 2 to provide the flow power of the cryogenic transport working fluid, so that the cryogenic transport working fluid can be transported to various parts of the heat-insulating box body 3 in the transmission pipeline 32, and the cold quantity is transferred to the inner container 31 through the transmission pipeline 32, which can reduce the temperature of the inner container 31 and its interior. The inner container 31 can be used as a cryogenic storage cabin. Through the active transportation of the cryogenic transport working fluid, the influence of the microgravity environment on the cryogenic transport working fluid is avoided, so that a more efficient and more uniform refrigeration effect can be achieved, meeting the needs of long-term and stable storage of various materials in the space environment.

[0035] The present invention is provided with a Stirling refrigerator 1 and a cryogenic pumping mechanism 2. The refrigeration quantity can be adjusted by adjusting the Stirling refrigerator 1, and the flow rate can be adjusted by adjusting the cryogenic pumping mechanism 2, so as to realize the dual adjustment of the temperature range and the cold quantity.

[0036] In one embodiment, the driving part is located inside the transmission pipeline 32. The driving part includes a driving cavity, a one-way inlet valve 26 and a one-way outlet valve 21 connected to the driving cavity. The one-way inlet valve 26 faces the oncoming flow direction and can only allow the cryogenic transport medium to enter unidirectionally. The one-way outlet valve 21 faces the outgoing flow direction and can only allow the cryogenic transport medium to flow out unidirectionally. Therefore, when the pressure in the driving cavity changes, under the combined action of the one-way inlet valve 26 and the one-way outlet valve 21, the unidirectional flow of the cryogenic transport medium can be achieved. To achieve the above object, the cryogenic pumping mechanism 2 includes, but is not limited to, a piston pump driven by a linear motor, a diaphragm pump, a pump driven by the piezoelectric effect, or other forms of compressors or pumps of similar forms. The forms of the one-way inlet valve 26 and the one-way outlet valve 21 include, but are not limited to, flat valves, reed valves, ring valves, mesh valves, or butterfly valves, etc.

[0037] 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 for driving the moving piston 22 to reciprocate. The piston cylinder 25 communicates with the driving cavity. Driven by the motor assembly 23, the moving piston 22 moves towards or away from the driving cavity. Thus, by expanding the volume of the piston cylinder 25 with the moving piston 22, the overall volume of the piston cylinder 25 and the driving cavity can be enlarged, and a negative pressure suction force is formed at the position of the one-way inlet valve 26. The cryogenic transport medium is sucked in through the one-way inlet valve 26 by using the negative pressure suction force. It should be noted that at this time, the one-way outlet valve 21 is in a closed state; by compressing the volume of the piston cylinder 25 with the moving piston 22, the overall volume of the piston cylinder 25 and the driving cavity can be reduced, and the cryogenic transport medium is discharged through the one-way outlet valve 21 by using the positive pressure thrust. It should be noted that at this time, the one-way inlet valve 26 is in a closed state. The structure of the moving piston 22 includes, but is not limited to, a single piston structure and a double piston structure. Adopting the former arrangement can reduce the space volume, and adopting the latter arrangement can cancel the vibration impact when moving towards or away from each other along the axis.

[0038] In one embodiment, the motor assembly 23 includes a housing, a rotor and a stator located inside the housing. The rotor can reciprocate axially relative to the stator. The rotor is supported inside the housing by a leaf spring 24, and the leaf spring 24 provides axial and radial supports for the movement of the rotor. The leaf spring 24 can adopt an Archimedean spiral type, a circular involute type, an eccentric circular involute type, etc. The leaf spring 24 and the piston cylinder 25 form a clearance seal to maintain the dynamic seal between the moving parts and the piston cylinder 25 during the movement process, and provide sufficient axial stiffness and radial support for the reciprocating movement of the moving parts.

[0039] In one embodiment, the cold finger 11 is located downstream of the driving part and close to the one-way outlet valve 21. That is to say, the cryogenic working medium discharged by the driving part through the one-way outlet valve 21 can reach the position of the cold finger 11 when it has relatively large kinetic energy, thereby improving the passability of the cryogenic working medium and ensuring that the cryogenic working medium can smoothly pass through the cold finger 11 and achieve cyclic flow in the transmission pipeline 32.

[0040] 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 cryogenic working medium, and the other side of the porous medium exchanges heat with the expansion cavity. By using the porous medium, the heat exchange efficiency between the cold finger 11 and the cryogenic working medium in the transmission pipeline 32 can be increased.

[0041] In one embodiment, the refrigerator body includes a linear compressor 12 and a phase modulation mechanism 13. The linear compressors 12 are arranged oppositely on both sides of the phase modulation mechanism 13. The linear compressors 12 and the phase modulation mechanism 13 are integrally arranged coaxially, and the axis of the cold finger 11 is perpendicular to the axis 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 heat preservation box 3 and extracting cold. The linear compressor 12 includes a compressor piston body, a compressor cylinder body and a long-life leaf spring, etc. The linear motor is used for driving and the opposed arrangement can reduce the influence of momentum. The reciprocating motion of the linear compressor 12 forms a compression cavity and a back pressure cavity to drive the cold finger 11. The phase modulation mechanism 13 includes a phase modulation cylinder body, a phase modulation piston body and a phase modulation reset elastic element, and the phase of the refrigerator body is modulated to improve the efficiency of the refrigerator body.

[0042] In one embodiment, the transmission pipelines 32 are distributed on the outer wall of the inner container 31. An accommodation space is formed inside the inner container 31. According to needs, the accommodation space can be divided into multiple storage rooms, and the outer wall positions of the inner container 31 corresponding to each storage room can be laid with transmission pipelines 32 of unequal lengths or quantities, so as to obtain storage rooms with different temperatures for storing items with different temperature requirements. The inner container 31 is made of an isothermal plate or a metal solid, which can achieve a good temperature transfer effect, effectively ensure that the low temperature of the transmission pipeline 32 is transferred to the inside of the inner container 31, make the pump-driven cold fluid refrigeration system or the refrigerator prepared therefrom have a more uniform temperature, and effectively improve the refrigeration effect. The metal solid inner container 31 has the characteristics of good heat conductivity, wear resistance and long life.

[0043] In one embodiment, the transmission pipeline 32 is made of annealed stainless steel pipeline, which can be effectively bent multiple times, facilitating layout and installation. The cryogenic transport medium is helium. As an ideal cryogenic transport medium, helium has the advantages of being green and environmentally friendly, high efficiency, large cooling capacity, and enabling rapid refrigeration in the deep cryogenic region. At the same time, helium has stable chemical properties and is not easily reactive 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 while ensuring high heat transfer efficiency.

[0044] In one embodiment, the cryogenic insulation layer 33 surrounds the transmission pipeline 32, reducing the cold quantity dissipated by the transmission pipeline 32 to the outside and ensuring the efficient transfer of the cryogenic transport medium to the inside of the inner container 31. The materials used for the cryogenic insulation layer 33 include polyurethane foam, perlite, glass wool, or a vacuum insulation layer, which can be the sole application of one material or a combination of multiple materials.

[0045] Specific examples are used in the present invention to illustrate the principles and implementation manners of the present invention. The description of the above embodiments is only for helping to understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A pump-driven cold fluid refrigeration system, characterized in that, Comprising: A thermal insulation box body, the thermal insulation box body includes an inner container, a transmission pipeline and a cryogenic insulation layer, the transmission pipeline is arranged between the inner container and the cryogenic insulation layer, and a cryogenic transport working medium is arranged in the transmission pipeline; A Stirling refrigerator, the Stirling refrigerator includes a refrigerator main body and a cold finger connected to the refrigerator main body, the cold finger is used for heat exchange with the cryogenic transport working medium; the cold head in the cold finger is filled with a porous medium, one side of the porous medium exchanges heat with the cryogenic transport working medium, and the other side of the porous medium exchanges heat with an expansion cavity; And a cryogenic pumping mechanism, the cryogenic pumping mechanism includes a pump body and a driving part connected to the pump body, the driving part is located in the transmission pipeline, the driving part 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 oncoming flow direction, and the one-way outlet valve faces the outgoing flow direction; The cold finger is located downstream of the driving part and close to the one-way outlet valve; The transmission pipeline is distributed on the outer wall of the inner container, and an accommodation space is formed inside the inner container. According to needs, the accommodation space is divided into multiple storage rooms, and transmission pipelines of unequal lengths or quantities are laid at the positions of the outer walls of the inner container corresponding to each storage room.

2. The pump-driven cold fluid refrigeration system according to claim 1, characterized in that: The pump body includes a piston cylinder, a moving piston located in the piston cylinder, and a motor assembly for driving the moving piston to reciprocate. The piston cylinder communicates with the driving cavity, and the moving piston is used to move towards or away from the driving cavity.

3. The pump-driven cold fluid refrigeration system according to claim 2, characterized in that: The motor assembly includes a housing and a rotor and a stator located inside the housing. The rotor is supported in the housing by a leaf spring.

4. The pump-driven cold fluid refrigeration system according to claim 1, characterized in that: The refrigerator main body includes a linear compressor and a phase adjustment mechanism. The linear compressor is arranged oppositely on both sides of the phase adjustment mechanism, and the axis of the cold finger is perpendicular to the axis of the linear compressor.

5. The pump-driven cold fluid refrigeration system according to claim 1, characterized in that: An accommodation space is formed inside the inner container, the accommodation space is divided into multiple storage rooms, and the inner container is made of an isothermal plate or a metal entity.

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

7. The pump-driven cold fluid refrigeration system according to claim 1, characterized in that: The cryogenic insulation layer surrounds the transmission pipeline, and the materials used for the cryogenic insulation layer include polyurethane foam, perlite, glass wool or a vacuum insulation layer.

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