CN-122015318-A - Refrigerating system capable of recovering expansion work

Abstract

The invention discloses a refrigerating system capable of recovering expansion work, which comprises a compression refrigerating unit and a regenerative refrigerating unit, wherein the compression refrigerating unit comprises a compressor, a high-pressure gas pipeline, a precooling section heat exchanger, an expansion device, a cold end heat exchanger and a low-pressure gas pipeline, the compressor comprises a compression cavity A and a compression piston sliding in the compression cavity A, the regenerative refrigerating unit comprises a pressure wave generator, a radiator, a heat regenerator, a heat absorber and a pressure wave transmission pipe, the heat absorber is used as a cold head for precooling a refrigerant in the precooling section heat exchanger, the pressure wave transmission pipe is internally provided with the slidable expansion piston, the compression piston of the compression refrigerating unit and the expansion piston of the regenerative refrigerating unit are coupled into a whole and slide in the compression cavity A to compress the refrigerant in the compression cavity A, the expansion work of the regenerative refrigerating unit is converted into the compression power of the compression refrigerating unit, the external energy input of the refrigerating system is reduced, and the energy utilization efficiency is improved.

Inventors

• XIAO JIAHUA
• HUANG YUXUAN

Assignees

• 山前（珠海）医疗科技有限公司

Dates

Publication Date

20260512

Application Date

20260409

Claims (20)

1. 1. A refrigeration system capable of recovering expansion work, comprising: The compression refrigeration unit comprises a compressor, a high-pressure gas pipeline, a precooling section heat exchanger, an expansion device, a cold end heat exchanger and a low-pressure gas pipeline; the expansion device is arranged on a high-pressure gas pipeline between the cold end heat exchanger and the pre-cooling section heat exchanger; the compressor comprises a compression cavity A and a compression piston sliding in the compression cavity A; the gas refrigerant in the compression cavity A flows to the pre-cooling section heat exchanger through the exhaust valve and the high-pressure gas pipeline after being pressurized by the compressor, and the high-pressure refrigerant is pre-cooled through the pre-cooling section heat exchanger and then expanded through the expansion device to generate cold energy; The regenerative refrigeration unit comprises a pressure wave generator for generating pressure fluctuation, a radiator, a heat regenerator, a heat absorber and a pressure wave transmission pipe which are sequentially connected along the pressure wave energy propagation direction, wherein a slidable expansion piston is arranged in the room temperature end of the pressure wave transmission pipe; The compression piston and the expansion piston are coupled to slide in the compression chamber A integrally to compress the gas refrigerant in the compression chamber A, so that the expansion work of the expansion piston is recovered as mechanical work for driving the compression piston to move.
2. 2. The refrigeration system of claim 1, wherein the compressor further comprises a drive device for providing motive power to the combination of the compression piston and the expansion piston, wherein the drive device is an electromagnetic drive device or a mechanical drive device, and wherein the refrigeration system comprises a phase cooperative control system for controlling the phase of motion of the expansion piston and the piston of the pressure wave generator such that the regenerative refrigeration unit produces a sufficient refrigeration effect.
3. 3. The refrigeration system according to claim 2, wherein said driving means is a first electromagnetic driving means, and a pair of said first electromagnetic driving means drives said compression piston to reciprocate in said compression chamber A by switching on an alternating current.
4. 4. The refrigeration system of claim 3, wherein said pressure wave generator comprises a compression chamber B, a piston sliding in said compression chamber B, and a pair of second electromagnetic driving means located outside said compression chamber B for driving said pressure wave generator piston to reciprocate in said compression chamber B by switching on an alternating current, said phase cooperative control system controlling the movement phases of said expansion piston and said pressure wave generator piston to convert the expansion work generated by said regenerative refrigeration unit into mechanical work for driving said compression piston to reciprocate.
5. 5. The refrigeration system of claim 1, wherein the regenerative refrigeration unit is a regenerative refrigerator with an expansion chamber, the regenerative refrigerator being a pulse tube refrigerator, a stirling refrigerator, or a thermo-acoustic refrigerator.
6. 6. The refrigeration system of claim 5, wherein the regenerative refrigeration unit is a pulse tube refrigerator, the pressure wave transmission tube is a pulse tube, and the expansion piston slides against a room temperature end inner wall of the pulse tube.
7. 7. The refrigeration system of claim 6, wherein said pressure wave generator has two sets of pistons moving in opposite directions and being disposed in opposition, said pistons of said two sets of pressure wave generators together forming a compression chamber B, the volume swept by the piston movements of said two sets of pressure wave generators doubling, and the vibrations caused by the piston movements of said two sets of pressure wave generators cancel each other.
8. 8. The refrigeration system of claim 7, wherein said compressor has two sets of said compression pistons moving in opposition and in opposition, said two sets of said compression pistons together forming a compression chamber a of the compressor, the volume swept by the movement of said two sets of said compression pistons doubling, and the vibrations caused by the movement of said two sets of said compression pistons cancel each other.
9. 9. The refrigeration system of claim 8, wherein two sets of said compressors are arranged in parallel or in series, wherein when said two sets of said compressors are arranged in parallel, said two sets of said compressors respectively provide said compressed refrigeration unit with high pressure gas having the same pressure ratio, and when said two sets of said compressors are arranged in series, the high pressure gas provided by the compressor of the previous stage is provided to said compressed refrigeration unit after being secondarily compressed by the compressor of the next stage, and the high pressure gas with a higher compression ratio is outputted.
10. 10. The refrigeration system of claim 1, wherein the pressure wave generator is a thermo-acoustic engine or a speaker.
11. 11. The refrigeration system of claim 1, wherein the compression refrigeration unit is a J-T throttling refrigeration unit, the J-T throttling refrigeration unit further comprises a J-T counterflow heat exchanger, a high pressure side inlet of the J-T counterflow heat exchanger is communicated with a cold end outlet of the pre-cooling section heat exchanger, a high pressure side outlet of the J-T counterflow heat exchanger is connected to a low pressure side inlet of the J-T counterflow heat exchanger through the expansion device and the cold end heat exchanger, a low pressure side outlet of the J-T counterflow heat exchanger is communicated with an air suction valve of the compressor, and high pressure refrigerant in the high pressure gas pipeline flows to the expansion device for throttling expansion after being pre-cooled by the pre-cooling section heat exchanger and the J-T counterflow heat exchanger in sequence, and cold energy is provided for cooling a load at the cold end heat exchanger.
12. 12. The refrigeration system of claim 11, wherein the compression refrigeration unit further comprises a reverse flow heat exchanger, a high pressure side inlet of the reverse flow heat exchanger being in communication with the discharge valve, a high pressure side outlet of the reverse flow heat exchanger being in communication with a hot side inlet of the pre-cooling stage heat exchanger, a low pressure side inlet of the reverse flow heat exchanger being in communication with a low pressure side outlet of the J-T reverse flow heat exchanger, a low pressure side outlet of the reverse flow heat exchanger being in communication with the suction valve.
13. 13. The refrigeration system of claim 1, wherein the expansion device is a throttle valve or an expander, and the high-pressure refrigerant in the high-pressure gas pipeline is throttled and expanded by the throttle valve or the expander after being precooled by the precooling section heat exchanger.
14. 14. A refrigeration system capable of recovering expansion work, comprising: The secondary refrigerant circulation unit comprises a fluid pump, a high-pressure fluid pipeline, a precooling section heat exchanger, a cold end heat exchanger and a low-pressure fluid pipeline; the system comprises a fluid pump, a pump cylinder, a low-pressure fluid pipeline, a precooling section heat exchanger, a cold end heat exchanger, a high-pressure refrigerating medium, a low-pressure refrigerating medium, a high-pressure refrigerating medium and a high-pressure refrigerating medium, wherein the fluid pump comprises a pump cylinder and a fluid pump piston sliding in the pump cylinder; The regenerative refrigeration unit comprises a pressure wave generator for generating pressure fluctuation, a radiator, a heat regenerator, a heat absorber and a pressure wave transmission pipe which are sequentially connected along the pressure wave energy propagation direction, wherein a slidable expansion piston is arranged in the room temperature end of the pressure wave transmission pipe; The fluid pump piston and the expansion piston are coupled to slide in the pump cylinder integrally to pressurize the coolant in the pump cylinder, so that the expansion work of the expansion piston is recovered as mechanical work for driving the fluid pump piston to move.
15. 15. A refrigeration system as recited in claim 14 wherein said fluid pump further comprises a drive means for providing motive power to a combination of a fluid pump piston of said coolant circulation unit and an expansion piston of said regenerative refrigeration unit, said drive means being either an electromagnetic drive or a mechanical drive, said refrigeration system including a phase cooperative control system for controlling the phase of movement of said expansion piston and the piston of said pressure wave generator such that said regenerative refrigeration unit produces a sufficient refrigeration effect.
16. 16. The refrigeration system of claim 15, wherein said driving means is a first electromagnetic driving means, and wherein a pair of said first electromagnetic driving means reciprocate said fluid pump piston within said pump cylinder by switching on an alternating current.
17. 17. The refrigeration system of claim 16, wherein said pressure wave generator comprises a compression chamber B, a piston sliding in said compression chamber B, and a pair of second electromagnetic driving means located outside said compression chamber B for driving said pressure wave generator piston to reciprocate in said compression chamber B by switching on an alternating current, said phase cooperative control system controlling the movement phases of said expansion piston and said pressure wave generator piston to convert the expansion work generated by said regenerative refrigeration unit into mechanical work for driving said fluid pump piston to reciprocate.
18. 18. The refrigeration system of claim 14, wherein the regenerative refrigeration unit is a regenerative refrigerator with an expansion chamber, the regenerative refrigerator being a pulse tube refrigerator, a stirling refrigerator, or a thermo-acoustic refrigerator.
19. 19. The refrigeration system of claim 18 wherein said regenerative refrigeration unit is a pulse tube refrigerator, said pressure wave transmission tube is a pulse tube, and said expansion piston slides against a room temperature end inner wall of said pulse tube.
20. 20. The refrigeration system as recited in claim 19 wherein said pressure wave generator has two sets of said pressure wave generators having pistons moving in opposite directions and being disposed in opposition, said pistons of said two sets of pressure wave generators together forming a compression chamber B, the volumes swept by the piston movements of said two sets of pressure wave generators being doubled, and the vibrations caused by the piston movements of said two sets of pressure wave generators being offset from each other.

Description

Refrigerating system capable of recovering expansion work Technical Field The invention relates to the technical field of low-temperature refrigeration, in particular to a refrigeration system capable of recovering expansion work, which is suitable for the technical field of ultra-low-temperature refrigeration required by quantum computing, superconducting magnets, space detection, basic physical research and the like. Background Joule-Thomson (J-T) throttling refrigerator has wide application in infrared detection, low temperature superconductivity, space science and other fields due to the advantages of simple structure, high reliability, no moving parts at cold end and the like. However, conventional J-T throttled refrigerators generally require a J-T compressor to provide a high-pressure refrigerant before throttling, and in order to achieve a refrigerating effect, the high-pressure side refrigerating temperature needs to be reduced below the switching temperature before throttling, and the high-pressure refrigerant before throttling must be sufficiently pre-cooled. In the prior art, an independent external precooling stage refrigerator (such as a pulse tube refrigerator and a thermoacoustic refrigerator) is generally adopted to precool the J-T pre-throttling gas. However, the regenerative refrigerators, such as pulse tube refrigerators and thermo-acoustic refrigerators, only provide cold energy, and the acoustic work or expansion work of pulse tube refrigerators and thermo-acoustic refrigerators is usually directly dissipated or only used for maintaining self circulation, is not recovered for driving a J-T compressor, does not participate in the generation of high-pressure refrigerant in a J-T throttling refrigeration system, and has the defects of low system integration level and low energy utilization efficiency. Therefore, there is a need for an efficient refrigeration system with high system integration and high energy utilization efficiency. Disclosure of Invention The invention aims to overcome the defects of the prior art, and aims to provide a refrigerating system which integrates compression refrigeration and regenerative refrigeration and can recover expansion work, the expansion work generated by the regenerative refrigeration unit is converted into the power of the compression piston in the compression refrigeration unit, and meanwhile, the heat absorber is used as a cold head to pre-cool the refrigerant in the pre-cooling section heat exchanger in the compression refrigeration unit, so that the integrated coupling of pre-cooling and power supply is realized, and the energy efficiency and the integration level of the system are improved. In order to solve the technical problems, the technical scheme of the invention is as follows: a refrigerating system capable of recovering expansion work comprises a compression refrigerating unit and a regenerative refrigerating unit; The compression refrigeration unit comprises a compressor, a high-pressure gas pipeline, a pre-cooling section heat exchanger, an expansion device, a cold end heat exchanger and a low-pressure gas pipeline, wherein the expansion device is arranged on the high-pressure gas pipeline between the cold end heat exchanger and the pre-cooling section heat exchanger; The refrigerant in the compression cavity A flows to the pre-cooling section heat exchanger through an exhaust valve and a high-pressure gas pipeline after being pressurized by the compressor, the high-pressure refrigerant is pre-cooled by the pre-cooling section heat exchanger and then is expanded by the expansion device, the cold energy generated by the refrigerant after expansion is subjected to cooling load removal by the cold end heat exchanger, and the refrigerant passing through the cold end heat exchanger flows back to the compression cavity A through a low-pressure gas pipeline and an air suction valve; The regenerative refrigeration unit comprises a pressure wave generator for generating pressure fluctuation, and a radiator, a heat regenerator, a heat absorber and a pressure wave transmission pipe which are sequentially connected along the pressure wave energy transmission direction, wherein a slidable expansion piston is arranged in the room temperature end of the pressure wave transmission pipe; The compression piston of the compression refrigeration unit and the expansion piston of the regenerative refrigeration unit are coupled to integrally slide in the compression cavity A to compress the gas refrigerant in the compression cavity A, so that the expansion work of the expansion piston of the regenerative refrigeration unit is recovered as mechanical work or part of mechanical work for driving the compression piston of the compression refrigeration unit to move. Further, the compressor further comprises a driving device for providing motion power for the combination of the compression piston of the compression type refrigerating unit and the expansion pisto