A single-stage GM refrigerator regenerator performance test device

Abstract

The present application relates to the field of cryogenic engineering technology, and specifically, to a single-stage G‑M refrigerator regenerator performance test device, including a vacuum chamber, a human-computer interaction system, a motor, and an air pipeline, wherein: a regenerator system and a cylinder system are arranged inside the vacuum chamber, and the regenerator system is connected to the cylinder system; the human-computer interaction system is respectively connected to the solenoid valves on the motor and the air pipeline; the motor is connected to the cylinder system; and the air pipeline is connected to the regenerator system and the cylinder system. The present application uses the technical means of the split design of the cylinder system and the regenerator system, and adopts the cooling capacity generated during the operation of the test device itself. Without changing the cylinder system and the driving mechanism, the application can accurately reflect the heat transfer characteristics, flow resistance characteristics, and thermal properties of the regenerator filler by conveniently changing the size, cold storage material, particle size, and filling rate of the regenerator, thereby providing a new way for the precise design of a single-stage G‑M refrigerator.

Description

Technical Field

[0001] The present application relates to the field of cryogenic engineering technology, and in particular to a single-stage GM refrigerator regenerator performance testing device. Background Art

[0002] The GM refrigerator was invented by Gifford and McMahon in 1956. It is a low-temperature refrigerator that uses Simon expansion, i.e. adiabatic degassing principle, to achieve refrigeration. It has the advantages of simple structure, reliable operation, stable performance, convenient operation, and long service life. It is the only low-temperature refrigerator that is industrially mass-produced and applied in the world. The main function of the single-stage GM refrigerator is to provide a stable and reliable cold source in the liquid nitrogen temperature zone for vacuum and low-temperature devices. At present, the GM refrigerator has been widely used in scientific research, superconducting technology, gas liquefaction and other fields.

[0003] Among the components of GM refrigerator, the regenerator is the core component for realizing heat exchange between cold and hot air flow. The heat transferred by it is 10-50 times greater than the cooling capacity of the refrigerator itself, and its heat recovery loss is the main cooling capacity loss of the refrigerator. Therefore, the performance of the regenerator has a decisive influence on the performance of the GM refrigerator. The heat recovery efficiency of the cold storage device must be ensured to be above 99%.

[0004] The design of conventional regenerators includes traditional calculation methods based on a set of heat transfer differential equations and numerical simulation methods newly developed in recent years. However, the regenerator material uses porous media as filler, the filling void volume ratio is large, and the flow and heat transfer conditions are quite complex. Therefore, it is very difficult to calculate through design. Establishing an experimental platform and simulating the temperature and pressure data of the regenerator during operation under real experimental conditions can intuitively and clearly reflect the performance and process parameters of the regenerator, which is an important way to achieve the design and optimization of the regenerator. Summary of the invention

[0005] The main purpose of the present application is to provide a single-stage GM refrigerator regenerator performance test device. Through the split design of the cylinder system and the regenerator system, the performance of the regenerator can be tested and optimized by only changing the filling ratio of the cold storage material, the particle size of the filling material and the size of the regenerator in the regenerator system.

[0006] In order to achieve the above-mentioned purpose, the present application provides a single-stage GM refrigerator regenerator performance testing device, including a vacuum chamber, a human-computer interaction system, a motor and an air pipeline, wherein: a regenerator system and a cylinder system are arranged inside the vacuum chamber, and the regenerator system is connected to the cylinder system; the human-computer interaction system is respectively connected to the motor and the solenoid valve on the air pipeline; the motor is connected to the cylinder system; and the air pipeline is connected to the regenerator system and the cylinder system.

[0007] Furthermore, the regenerator system includes a fixed frame, a regenerator cylinder and a cold storage material, wherein: the cold storage material is arranged inside the regenerator cylinder; the regenerator cylinder is fixedly arranged inside the fixed frame, an upper sealing end surface is arranged above the regenerator cylinder, and a lower sealing end surface is arranged below the regenerator cylinder.

[0008] Furthermore, a pressure cover is arranged above the upper sealing end face, and the upper sealing end face includes an upper seat, an upper sealing ring and an upper straightening felt, wherein: the upper seat is connected to the gas pipeline; the upper sealing ring is arranged in the groove of the upper seat; the upper straightening felt is arranged between the upper seat and the regenerator cylinder.

[0009] Furthermore, the lower sealing end face includes a lower seat, a lower sealing ring and a lower straightening felt, wherein: the lower seat is connected to the cylinder system through a metal short pipe; the lower sealing ring is arranged in the groove of the lower seat; and the lower straightening felt is arranged between the lower seat and the regenerator cylinder.

[0010] Furthermore, a threaded opening is provided on the side of the regenerator cylinder for fixedly connecting the temperature sensor and the pressure sensor.

[0011] Furthermore, the temperature sensor and the pressure sensor are both connected to the human-computer interaction system.

[0012] Furthermore, the cylinder system includes a flange, a cylinder and a push piston, wherein: the cylinder is fixed inside the vacuum chamber through the flange; the push piston is connected to the motor, and a self-lubricating seal is provided between the push piston and the cylinder; and the bottom of the cylinder is connected to the lower seat through a metal short tube.

[0013] Furthermore, a solenoid valve is provided on the gas pipeline.

[0014] Furthermore, the upper sealing ring and the lower sealing ring are both polytetrafluoroethylene sealing rings.

[0015] Furthermore, the material of the push piston is solid bakelite material.

[0016] The single-stage GM refrigerator regenerator performance test device provided by the present invention has the following beneficial effects:

[0017] This application adopts the technical means of split design of cylinder system and regenerator system, and uses the cooling capacity generated during the operation of the test device itself. Without changing the cylinder system and the driving mechanism, it can accurately reflect the heat transfer characteristics, flow resistance characteristics and thermal properties of the regenerator filler by conveniently changing the size, cold storage material, particle size and filling rate of the regenerator, thereby providing a new approach for the precise design of single-stage GM refrigerators. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings constituting a part of this application are used to provide a further understanding of this application, so that other features, purposes and advantages of this application become more obvious. The schematic embodiment drawings and their descriptions of this application are used to explain this application and do not constitute an improper limitation on this application. In the drawings:

[0019] Figure 1 It is a structural schematic diagram of a single-stage GM refrigerator regenerator performance test device provided according to an embodiment of the present application;

[0020] Figure 2 Schematic diagram of a regenerator of a single-stage GM refrigerator regenerator performance test device provided according to an embodiment of the present application;

[0021] Figure 3 Schematic diagram of the upper base of a single-stage GM refrigerator regenerator performance test device provided according to an embodiment of the present application;

[0022] In the figure: 1-vacuum chamber, 2-human-machine interaction system, 3-motor, 4-gas pipeline, 5-regenerator system, 51-fixed frame, 52-regenerator cylinder, 53-cold storage material, 54-pressure cover, 551-upper card seat, 552-upper sealing ring, 553-upper rectification felt, 561-lower card seat, 562-lower sealing ring, 563-lower rectification felt, 57-threaded opening, 6-cylinder system, 61-flange, 62-cylinder, 63-push piston, 64-metal short pipe, 7-temperature sensor, 8-pressure sensor, 9-solenoid valve. DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0024] like Figure 1-3 As shown, the present application provides a single-stage GM refrigerator regenerator performance test device, including a vacuum chamber 1, a human-computer interaction system 2, a motor 3 and an air pipeline 4, wherein: a regenerator system 5 and a cylinder system 6 are arranged inside the vacuum chamber 1, and the regenerator system 5 is connected to the cylinder system 6; the human-computer interaction system 2 is respectively connected to the motor 3 and the solenoid valve 9 on the air pipeline 4; the motor 3 is connected to the cylinder system 6; and the air pipeline 4 is connected to the regenerator system 5.

[0025] Specifically, the single-stage GM refrigerator regenerator performance test device provided in the embodiment of the present application is used as a theoretical verification or structural optimization of the regenerator design link. The cylinder system 6 and the regenerator system 5 are split structures. The regenerator system 5 is different from the traditional GM refrigerator structure and is placed outside the cylinder 62. Without disassembling the cylinder 62, the regenerator performance can be conveniently tested and tested by changing the filling ratio of the cold storage material 53, changing the particle size of the filling material, and changing the size of the regenerator. The overall circulation physical framework is realized by the human-computer interaction system 2. The speed of the electromagnetic valve 9 and the motor 3 is controlled by the set timing. The stable output of the cold source of the test platform is achieved by the set opening and closing of the electromagnetic valve 9 and the phase coupling action of the eccentric crank mechanism. The comprehensive judgment of the heat transfer characteristics, flow resistance characteristics and thermal properties of the regenerator seasoning is achieved by real-time monitoring of the working condition changes of the temperature sensor 7 and the pressure sensor 8 set in the regenerator. The vacuum chamber 1 is mainly used to provide a vacuum environment for the test device. During the test, the vacuum chamber 1 is evacuated to 10 by a molecular pump vacuum unit. -2 Pa level, the human-computer interaction system 2 is mainly used for the transmission of control commands and the collection of various parameters, and is connected to the cylinder system 6 through the motor 3, and is connected to the regenerator system 5 through the gas pipeline 4. During the test, according to the set timing, the coupling action of the eccentric crankshaft mechanism of the motor 3 and the electromagnetic valve 9 in the gas pipeline 4 accurately controls the high-purity helium entering and discharging the regenerator cylinder 52 and the cylinder 62, and the corresponding cooling capacity and cooling temperature are obtained through the GM refrigeration cycle of the test device itself, thereby generating a temperature gradient in the regenerator system 5. The human-computer interaction system 2 can collect the temperature and pressure data installed in the regenerator system 5 in real time, and realize the monitoring of performance parameters such as cold storage efficiency and regenerator pressure loss during the test.

[0026] Furthermore, the regenerator system 5 includes a fixing frame 51, a regenerator cylinder 52 and a cold storage material 53, wherein: the cold storage material 53 is arranged inside the regenerator cylinder 52; the regenerator cylinder 52 is arranged inside the fixing frame 51, and an upper sealing end face is arranged above the regenerator cylinder 52, and a lower sealing end face is arranged below the regenerator cylinder 52. The regenerator cylinder 52 is fixed on the fixing frame 51, and a cold storage material 53 is arranged inside. The upper part is connected to the gas pipeline 4 through the upper sealing end face to form a seal of the high-purity helium inlet and exhaust channel, and the lower part is connected to the metal short pipe 64 through the lower sealing end face to form a seal of the cold transmission channel. In addition, in the process of adding the cold storage material 53, a patch temperature sensor group (T1-T3) is arranged inside the regenerator cylinder 52, and the radial temperature distribution inside the regenerator can be collected during the operation of the test device.

[0027] Furthermore, a gland 54 is arranged above the upper sealing end surface, and the upper sealing end surface includes an upper seat 551, an upper sealing ring 552 and an upper straightening felt 553, wherein: the upper seat 551 is connected to the gas pipeline 4; the upper sealing ring 552 is arranged in the groove of the upper seat 551; the upper straightening felt 553 is arranged between the upper seat 551 and the regenerator cylinder 52. The upper seat 551 is provided with an inlet and outlet port, an annular sealing groove for sealing the helium inside the regenerator with the outside world, and a side wedge-shaped sealing groove for sealing between the seat and the regenerator cylinder 52. The annular sealing groove of the upper seat 551 is connected to the gland 54 through the upper sealing ring 552. After the gland 54 and the upper seat 551 are tightened by threaded fastening, the deformation of the upper sealing ring 552 forms an isolation between the internal airflow of the regenerator system 5 and the outside world.

[0028] Furthermore, the lower sealing end surface includes a lower card seat 561, a lower sealing ring 562 and a lower straightening felt 563, wherein: the lower card seat 561 is connected to the cylinder system 6 through a metal short tube 64; the lower sealing ring 562 is arranged in the groove of the lower card seat 561; the lower straightening felt 563 is arranged between the lower card seat 561 and the regenerator cylinder 52. The lower card seat 561 is also provided with an inlet and outlet interface, an annular sealing groove for sealing the helium inside the regenerator with the outside, and a side wedge-shaped sealing groove for sealing between the card seat and the regenerator cylinder 52. The annular sealing groove of the lower card seat 561 is connected to the bottom of the regenerator cylinder 52 through the lower sealing ring 562.

[0029] Specifically, after the lower sealing ring 562 is installed in the groove of the lower clamping seat 561, it is fastened to the lower end face of the heat exchanger cylinder 52 by the thermal expansion method to form the lower sealing end face of the heat exchanger system 5, and the lower straightening felt 563 is installed in the lower end face of the heat exchanger cylinder 52, and then the cold storage material 53 is added, and then the whole is installed in the fixing frame 51. The lower end face of the heat exchanger cylinder 52 is positioned in the positioning groove at the bottom of the fixing frame 51 through the lower sealing ring 562 in the groove of the lower clamping seat 561. After the upper straightening felt 553 is added to the upper end face of the heat exchanger, the upper sealing ring 552 is installed in the groove of the upper clamping seat 551, and it is also fastened to the upper end face of the heat exchanger cylinder 52 by the thermal expansion method to form the upper sealing end face of the heat exchanger system 5, and then it is fastened by the pressure cover 54 to form the overall heat exchanger system 5.

[0030] Furthermore, a threaded opening 57 is also provided on the side of the regenerator cylinder 52, which is mainly used to connect with the temperature sensor 7 and the pressure sensor 8. A stainless steel wire sleeve is provided in the threaded connection port, and a rubber seal is used between the pressure sensor 8 and the temperature sensor 7 and the threaded connection port. In addition, according to the actual test situation, a threaded connection port can also be provided at the end face of the upper clamping seat 551 and the end face of the lower clamping seat 561, which is also used to connect the temperature sensor 7 and the pressure sensor 8 to monitor the pressure and temperature changes of the regenerator inlet and outlet, respectively, and then reflect the pressure loss and heat recovery efficiency of the regenerator. A temperature or pressure sensor can also be installed on the side of the regenerator cylinder 52 to monitor the radial and longitudinal temperature and pressure conditions of the corresponding parts of the regenerator.

[0031] Furthermore, the temperature sensor 7 and the pressure sensor 8 are both connected to the human-computer interaction system 2. The temperature sensor 7 and the pressure sensor 8 are mainly used to sense the temperature and pressure data of the corresponding parts, and collect and record the temperature and pressure data in real time through the human-computer interaction system 2 to reflect the heat transfer characteristics, flow resistance characteristics and thermal properties of the regenerator seasoning of the regenerator, thereby realizing the test of the regenerator performance, and the temperature gradient during the regenerator test is generated by the GM refrigeration cycle of the test device itself.

[0032] Furthermore, the cylinder system 6 includes a flange 61, a cylinder 62 and a push piston 63, wherein: the cylinder 62 is fixed inside the vacuum chamber 1 through the flange 61; the push piston 63 is connected to the motor 3, and a self-lubricating seal is provided between the push piston 63 and the cylinder 62; the bottom of the cylinder 62 is connected to the lower holder 561 through a metal short tube 64. The cylinder system 6 is fixed inside the vacuum chamber 1 through the CF flange 61 as a whole, and the cylinder 62 has the same characteristics as the GM refrigerator. The cylinder 62 contains a push piston 63, and the upper part of the push piston 63 is connected to the driving motor 3. Under the rotary motion of the eccentric crank mechanism of the motor 3, the push piston 63 reciprocates up and down in the cylinder 62. To prevent gas blowby between the cold end and the hot end of the cylinder 62, the push piston 63 and the cylinder 62 are sealed by a self-lubricating material, and the bottom of the cylinder 62 is connected to the lower holder 561 through a metal short tube 64 with a multi-layer insulation structure, forming a cold transmission channel between the cylinder and the regenerator.

[0033] Furthermore, a solenoid valve 9 is provided on the gas pipeline 4. The solenoid valve 9 is mainly used to control the inlet and outlet gas of the regenerator system 5 and the cylinder system 6. When the vacuum degree of the vacuum chamber 1 reaches the test environment standard, the human-machine interaction system 2 controls the speed of the motor 3 and the opening and closing of the solenoid valve 9 according to the set timing, and realizes the GM refrigeration cycle through the phase relationship between the speed of the motor 3 and the opening and closing of the solenoid valve 9, generating cold capacity and corresponding refrigeration temperature, and then collects and records the temperature and pressure data in real time through the temperature sensor 7 and pressure sensor 8 installed in the regenerator, reflecting the heat transfer characteristics, flow resistance characteristics of the regenerator and the thermal properties of the regenerator seasoning.

[0034] Furthermore, the upper sealing ring 552 and the lower sealing ring 562 are both polytetrafluoroethylene sealing rings. The upper sealing ring 552 and the lower sealing ring 562 are preferably polytetrafluoroethylene sealing rings, which have good sealing effects.

[0035] Furthermore, the material of the push piston 63 is solid bakelite material. The push piston 63 is preferably made of solid bakelite material with small thermal conductivity and low specific gravity.

[0036] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A single-stage GM refrigerator regenerator performance test device, characterized in that: It includes a vacuum chamber, a human-machine interaction system, a motor and a gas supply pipeline, among which: A regenerator system and a cylinder system are provided inside the vacuum chamber, and the regenerator system is connected to the cylinder system; The human-machine interaction system is connected to the motor and the air supply pipeline respectively; The motor is connected to the cylinder system; The gas supply pipeline is connected to the regenerator system; The regenerator system comprises a fixing frame, a regenerator cylinder and a cold storage material, wherein: The cold storage material is arranged inside the regenerator cylinder; The regenerator cylinder is fixedly arranged inside the fixing frame, an upper sealing end surface is arranged above the regenerator cylinder, and a lower sealing end surface is arranged below the regenerator cylinder; A gland is disposed above the upper sealing end surface, and the upper sealing end surface includes an upper seat, an upper sealing ring and an upper rectification felt, wherein: The upper holder is connected to the air supply pipeline; The upper sealing ring is arranged in the groove of the upper card seat; The upper straightening felt is arranged between the upper holder and the regenerator cylinder; The lower sealing end surface includes a lower seat, a lower sealing ring and a lower straightening felt, wherein: The lower card seat is connected to the cylinder system through a metal short pipe; The lower sealing ring is arranged in the groove of the lower card seat; The lower straightening felt is arranged between the lower card seat and the regenerator cylinder; The cylinder system comprises a flange, a cylinder and a push piston, wherein: The cylinder is fixed inside the vacuum chamber via the flange; The push piston is connected to the motor, and a self-lubricating seal is provided between the push piston and the cylinder; The bottom of the cylinder is connected to the lower seat through a short metal pipe; The upper sealing ring and the lower sealing ring are both polytetrafluoroethylene sealing rings; The material of the push piston is solid bakelite material.

2. The single-stage GM refrigerator regenerator performance test device according to claim 1, characterized in that: The side of the regenerator cylinder is also provided with a threaded opening for fixedly connecting a temperature sensor and a pressure sensor.

3. The single-stage GM refrigerator regenerator performance test device according to claim 2, characterized in that: The temperature sensor and the pressure sensor are both connected to the human-computer interaction system.

4. The single-stage GM refrigerator regenerator performance test device according to claim 1, characterized in that: The air supply pipeline is provided with a solenoid valve.

Images