A multi-temperature zone low-temperature heat exchanger testing method and device

Abstract

The present invention discloses a multi-temperature zone cryogenic heat exchanger testing method and device, wherein a compressor provides circulating power for a circulating helium medium; a first-stage cold head assembly cools the circulating helium medium to a liquid nitrogen temperature zone; a second-stage cold head assembly further cools the circulating helium medium to a liquid hydrogen temperature zone; a GM refrigerator provides cooling capacity for the first-stage cold head assembly and the second-stage cold head assembly; a throttle valve further cools the circulating helium medium to a liquid helium temperature zone; and a simulated load is used to provide a load for a test loop. The test device with the above-mentioned optimized design is simple and reliable, and the multi-stage cold head assembly adopts a single cold source of a G‑M refrigerator, and provides multiple test temperature zones for the heat exchanger to be tested through the multi-stage cold head assembly and the throttle valve, thereby realizing simultaneous testing of cryogenic heat exchangers in three temperature zones: liquid nitrogen temperature zone, liquid hydrogen temperature zone, and liquid helium temperature zone. The test efficiency is high, and the commonly used temperature zones in the low-temperature field are fully covered, and the stability is good.

Description

Technical Field

[0001] The present invention relates to the technical field of low-temperature heat exchanger testing, and in particular to a multi-temperature zone low-temperature heat exchanger testing method and device. Background Art

[0002] With the development and application of cryogenic technology, cryogenic heat exchangers have also been widely used. In engineering applications, in order to verify the design parameters and performance of cryogenic heat exchangers, it is necessary to test the performance of the heat exchanger in order to compare and analyze it with the theoretical design. Existing cryogenic heat exchanger testing methods generally have testing methods for specific working conditions in a single liquid nitrogen temperature zone, such as the application number CN201710407482.6, a test device for testing the performance of heat exchangers in a large Reynolds number range at low temperatures. In addition, in order to solve the problem of heat exchanger testing under multiple temperature zones, there are also heat exchanger testing methods for two temperature zones of liquid nitrogen and liquid hydrogen, such as the application number CN202210900558.X, a multi-temperature zone testing device and method for packed plate-fin heat exchangers under low temperature conditions. However, this will increase costs and complicate the structure of the entire system. In addition, multiple temperature zones need to be tested separately during testing, which seriously affects the efficiency of the test operation. Summary of the invention

[0003] In order to solve the technical problems existing in the background technology, the present invention proposes a multi-temperature zone low-temperature heat exchanger testing method and device.

[0004] The present invention provides a multi-temperature zone low-temperature heat exchanger testing method and device, comprising: a compressor, a primary cold head assembly, a secondary cold head assembly, a GM refrigerator, a throttle valve and a simulated load;

[0005] The compressor is used to provide circulation power for the circulating helium medium;

[0006] The first-stage cold head assembly has a first-stage cooling inlet and a first-stage cooling outlet, and the first-stage cold head assembly is used to cool the circulating helium medium to a liquid nitrogen temperature zone;

[0007] The secondary cold head assembly has a secondary cooling inlet and a secondary cooling outlet, and the secondary cold head assembly is used to further cool the circulating helium medium after being cooled by the primary cold head assembly to a liquid hydrogen temperature zone;

[0008] The GM refrigerator is used to provide cooling capacity for the primary cold head assembly and the secondary cold head assembly;

[0009] The throttle valve has a three-stage cooling inlet and a three-stage cooling outlet, which is used to further cool the circulating helium medium after being cooled by the secondary cold head assembly to the liquid helium temperature zone;

[0010] The simulated load is connected in series downstream of the three-stage cooling outlet of the throttle valve to provide a load for the test loop.

[0011] Preferably, the compressor is connected between the primary cooling inlet of the primary cold head assembly and the output end of the simulated load;

[0012] The testing device also includes a main regulating valve and a bypass regulating valve. A regulating pipeline is connected between the input end and the output end of the compressor. The bypass regulating valve is located on the regulating pipeline, and the main regulating valve is located at the output end of the compressor.

[0013] Preferably, it also includes a flow meter, which is located at the output end of the compressor and downstream of the main regulating valve.

[0014] Preferably, it also includes a cold box, in which a chamber for accommodating a primary heat exchanger, a secondary heat exchanger and a tertiary heat exchanger is provided, and a primary cold head assembly, a secondary cold head assembly, a throttle valve and a simulated load are all arranged in the cold box.

[0015] Preferably, a first heater is provided on the simulated load;

[0016] and / or, the primary cold head assembly includes a second heater;

[0017] And / or, the secondary cold head assembly includes a third heater.

[0018] Preferably, it also includes a first heat exchanger, the hot flow inlet of the first heat exchanger is connected to the output end of the compressor, the hot flow outlet of the first heat exchanger is connected to the input end of the first-stage cold head assembly; the cold flow outlet of the first heat exchanger is connected to the input end of the compressor.

[0019] Preferably, a second heat exchanger is also included, the hot flow inlet of the second heat exchanger is connected to the output end of the first-stage cold head assembly, the hot flow outlet of the second heat exchanger is connected to the input end of the second-stage cold head assembly; the cold flow outlet of the second heat exchanger is connected to the cold flow inlet of the first heat exchanger.

[0020] In the present invention, the proposed multi-temperature zone cryogenic heat exchanger test device, the compressor provides circulation power for the circulating helium medium; the first-stage cold head assembly cools the circulating helium medium to the liquid nitrogen temperature zone; the second-stage cold head assembly further cools the circulating helium medium to the liquid hydrogen temperature zone; the GM refrigerator provides cooling capacity for the first-stage cold head assembly and the second-stage cold head assembly; the throttle valve further cools the circulating helium medium to the liquid helium temperature zone; the simulated load is used to provide a load for the test loop. The test device with the above-mentioned optimized design is simple and reliable. The multi-stage cold head assembly adopts a single cold source of the GM refrigerator, and provides multiple test temperature zones for the heat exchanger to be tested through the multi-stage cold head assembly and the throttle valve, thereby realizing simultaneous testing of cryogenic heat exchangers in three temperature zones: liquid nitrogen temperature zone, liquid hydrogen temperature zone, and liquid helium temperature zone. The test efficiency is high, and the commonly used temperature zones in the low-temperature field are fully covered, and the stability is good.

[0021] The present invention also proposes a multi-temperature zone low-temperature heat exchanger testing method based on the multi-temperature zone low-temperature heat exchanger testing device, comprising the following steps:

[0022] The circulating helium medium is sent to the hot flow inlet of the first-stage heat exchanger, the circulating helium medium output from the hot flow outlet of the first-stage heat exchanger is cooled to the liquid nitrogen temperature zone through the first-stage cold head assembly, and then the circulating helium medium is cooled to the liquid hydrogen temperature zone through the second-stage cold head assembly, and finally the circulating helium medium is cooled to the liquid helium temperature zone through the throttle valve and then sent to the simulated load, and the circulating helium medium output from the simulated load is sequentially sent to the cold flow channel of the first-stage heat exchanger;

[0023] The performance parameters of the primary heat exchanger are calculated based on the temperature, pressure and flow rate of the hot flow inlet, hot flow outlet, cold flow inlet and cold flow outlet of the primary heat exchanger.

[0024] The present invention also proposes a multi-temperature zone low-temperature heat exchanger testing method based on the multi-temperature zone low-temperature heat exchanger testing device, comprising the following steps:

[0025] The circulating helium medium is sent to the hot flow inlet of the first-stage heat exchanger, the circulating helium medium output from the hot flow outlet of the first-stage heat exchanger is cooled to the liquid nitrogen temperature zone through the first-stage cold head assembly, and then sent to the hot flow inlet of the second-stage heat exchanger, the circulating helium medium output from the hot flow outlet of the second-stage heat exchanger is cooled to the liquid hydrogen temperature zone through the second-stage cold head assembly, and then the circulating helium medium is cooled to the liquid helium temperature zone through the throttle valve and then sent to the simulated load, and the circulating helium medium output from the simulated load is sequentially sent to the cold flow channels of the second-stage heat exchanger and the first-stage heat exchanger;

[0026] Calculate the performance parameters of the primary heat exchanger according to the temperature, pressure and flow rate of the hot flow inlet, hot flow outlet, cold flow inlet and cold flow outlet of the primary heat exchanger;

[0027] And / or, the performance parameters of the secondary heat exchanger are calculated based on the temperature, pressure and flow rate of the hot flow inlet, hot flow outlet, cold flow inlet and cold flow outlet of the secondary heat exchanger.

[0028] The present invention also proposes a multi-temperature zone low-temperature heat exchanger testing method based on the multi-temperature zone low-temperature heat exchanger testing device, comprising the following steps:

[0029] Sending the circulating helium medium to the hot flow inlet of the first-stage heat exchanger, cooling the circulating helium medium output from the hot flow outlet of the first-stage heat exchanger to the liquid nitrogen temperature zone through the first-stage cold head assembly, and then sending it to the hot flow inlet of the second-stage heat exchanger, cooling the circulating helium medium output from the hot flow outlet of the second-stage heat exchanger to the liquid hydrogen temperature zone through the second-stage cold head assembly, and then sending it to the hot flow inlet of the third-stage heat exchanger, cooling the circulating helium medium output from the hot flow outlet of the third-stage heat exchanger to the liquid helium temperature zone through the throttle valve, and then sending it to the simulated load, and sending the circulating helium medium output from the simulated load to the cold flow channels of the third-stage heat exchanger, the second-stage heat exchanger, and the first-stage heat exchanger in sequence;

[0030] Calculate the performance parameters of the primary heat exchanger according to the temperature, pressure and flow rate of the hot flow inlet, hot flow outlet, cold flow inlet and cold flow outlet of the primary heat exchanger;

[0031] and / or, calculating the performance parameters of the secondary heat exchanger based on the temperature, pressure and flow rate of the hot flow inlet, hot flow outlet, cold flow inlet and cold flow outlet of the secondary heat exchanger;

[0032] And / or, the performance parameters of the three-stage heat exchanger are calculated according to the temperature, pressure and flow rate of the hot flow inlet, hot flow outlet, cold flow inlet and cold flow outlet of the three-stage heat exchanger.

[0033] In the present invention, the proposed multi-temperature zone low-temperature heat exchanger testing method has a technical effect similar to that of the above-mentioned testing device, so it will not be described in detail. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a structural schematic diagram of an implementation of a multi-temperature zone low-temperature heat exchanger testing device proposed by the present invention. DETAILED DESCRIPTION

[0035] like Figure 1 As shown, Figure 1 This is a structural schematic diagram of an implementation of a multi-temperature zone low-temperature heat exchanger testing device proposed by the present invention.

[0036] Reference Figure 1 The present invention proposes a multi-temperature zone low-temperature heat exchanger test device, comprising: a compressor 1, a primary cold head assembly 51, a secondary cold head assembly 52, a GM refrigerator 5, a throttle valve 9 and a simulated load 10;

[0037] The compressor 1 is used to provide circulation power for the circulating helium medium;

[0038] The first-stage cold head assembly 51 has a first-stage cooling inlet and a first-stage cooling outlet, and the first-stage cold head assembly 51 is used to cool the circulating helium medium to the liquid nitrogen temperature zone;

[0039] The secondary cold head assembly 52 has a secondary cooling inlet and a secondary cooling outlet, and the secondary cold head assembly 52 is used to further cool the circulating helium medium after being cooled by the primary cold head assembly 51 to the liquid hydrogen temperature zone;

[0040] The GM refrigerator 5 is used to provide cooling capacity for the primary cold head assembly 51 and the secondary cold head assembly 52;

[0041] The throttle valve 9 has a three-stage cooling inlet and a three-stage cooling outlet, which is used to further cool the circulating helium medium after being cooled by the secondary cold head assembly 52 to the liquid helium temperature zone;

[0042] The simulated load 10 is connected in series downstream of the three-stage cooling outlet of the throttle valve 9 to provide a load for the test loop.

[0043] During the specific testing process of the multi-temperature zone low-temperature heat exchanger testing device of this embodiment, the output end of the compressor is connected in series with the heat flow channel of the first-stage heat exchanger 6, the first-stage cold head assembly 51, the heat flow channel of the second-stage heat exchanger 7, the second-stage cold head assembly 52, the heat flow channel of the third-stage heat exchanger 8 and the throttle valve 9, and then connected to the simulated load 10. The output end of the simulated load is connected to the cold flow channels of the third-stage heat exchanger 8, the second-stage heat exchanger 7 and the first-stage heat exchanger 6 in sequence and then returns to the input end of the compressor 1 to form a test loop.

[0044] The first, second and third stage heat exchangers are the heat exchangers to be tested, and their structural types are not fixed, and they can be heat exchangers commonly used in the low temperature field, such as plate type and sleeve type. The working temperature zones of the heat exchangers respectively work in the liquid nitrogen temperature zone, the liquid hydrogen temperature zone and the liquid helium temperature zone. One path of each heat exchanger is a downstream high-pressure hot flow path, and the other path is a countercurrent low-pressure cold flow path. The hot flow path working fluid exchanges heat with the cold flow path working fluid, the hot flow path working fluid is cooled, and the cold flow path working fluid is heated.

[0045] In the specific test process, the compressor 1 first sends the circulating helium medium to the hot flow inlet of the primary heat exchanger 6 for primary cooling, and the circulating helium medium output from the hot flow outlet of the primary heat exchanger 6 is cooled to the liquid nitrogen temperature zone of 60-80K through the primary cold head component 51, and then sent to the hot flow inlet of the secondary heat exchanger 7 for secondary cooling, and the circulating helium medium output from the hot flow outlet of the secondary heat exchanger 7 is cooled to the liquid hydrogen temperature zone through the secondary cold head component 52 and then sent to the hot flow inlet of the tertiary heat exchanger 8, and the circulating helium medium output from the hot flow outlet of the tertiary heat exchanger 8 is cooled to the liquid helium temperature zone through the throttle valve 9 and then sent to the simulated load 10, and after the circulating helium medium output from the simulated load 10 is sequentially sent to the cold flow channels of the tertiary heat exchanger 8, the secondary heat exchanger 7 and the primary heat exchanger 6, the low-temperature circulating medium returns to normal temperature and returns to the compressor to realize a closed cycle. The performance parameters of the first-stage heat exchanger 6 are calculated based on the temperature, pressure and flow meter 4 of the hot flow inlet, hot flow outlet, cold flow inlet and cold flow outlet of the first-stage heat exchanger 6; the performance parameters of the second-stage heat exchanger 7 are calculated based on the temperature, pressure and flow meter 4 of the hot flow inlet, hot flow outlet, cold flow inlet and cold flow outlet of the second-stage heat exchanger 7; the performance parameters of the tertiary heat exchanger 8 are calculated based on the temperature, pressure and flow meter 4 of the hot flow inlet, hot flow outlet, cold flow inlet and cold flow outlet of the tertiary heat exchanger 8.

[0046] In this embodiment, the proposed multi-temperature zone cryogenic heat exchanger test method and device, the compressor provides circulation power for the circulating helium medium; the first-stage cold head assembly cools the circulating helium medium to the liquid nitrogen temperature zone; the second-stage cold head assembly further cools the circulating helium medium to the liquid hydrogen temperature zone; the GM refrigerator provides cooling capacity for the first-stage cold head assembly and the second-stage cold head assembly; the throttle valve further cools the circulating helium medium to the liquid helium temperature zone; the simulated load is used to provide a load for the test loop. The test device with the above-mentioned optimized design is simple and reliable. The multi-stage cold head assembly adopts a single cold source of the GM refrigerator, and provides multiple test temperature zones for the heat exchanger to be tested through the multi-stage cold head assembly and the throttle valve, thereby realizing the simultaneous testing of cryogenic heat exchangers in three temperature zones: liquid nitrogen temperature zone, liquid hydrogen temperature zone, and liquid helium temperature zone. The test efficiency is high, and the commonly used temperature zones in the low temperature field are fully covered, and the stability is good.

[0047] In addition, the test device of this embodiment can also test the primary heat exchanger and the secondary heat exchanger at the same time as needed. At this time, the circulating helium medium is sent to the hot flow inlet of the primary heat exchanger 6, and the circulating helium medium output from the hot flow outlet of the primary heat exchanger 6 is cooled to the liquid nitrogen temperature zone through the primary cold head component 51 and then sent to the hot flow inlet of the secondary heat exchanger 7, and the circulating helium medium output from the hot flow outlet of the secondary heat exchanger 7 is cooled to the liquid hydrogen temperature zone through the secondary cold head component 52, and then the circulating helium medium is cooled to the liquid helium temperature zone through the throttle valve 9 and then sent to the simulated load 10, and the circulating helium medium output from the simulated load 10 is sent to the secondary heat exchanger 7 and the cold flow channel of the primary heat exchanger 6 in turn; the performance parameters of the primary heat exchanger 6 are calculated according to the temperature, pressure and flowmeter 4 of the hot flow inlet, hot flow outlet, cold flow inlet and cold flow outlet of the primary heat exchanger 6; the performance parameters of the secondary heat exchanger 7 are calculated according to the temperature, pressure and flowmeter 4 of the hot flow inlet, hot flow outlet, cold flow inlet and cold flow outlet of the secondary heat exchanger 7.

[0048] Similarly, the test device of this embodiment can also test the primary heat exchanger separately as needed. At this time, the circulating helium medium is sent to the hot flow inlet of the primary heat exchanger 6, and the circulating helium medium output from the hot flow outlet of the primary heat exchanger 6 is cooled to the liquid nitrogen temperature zone through the primary cold head assembly 51, and then the circulating helium medium is cooled to the liquid hydrogen temperature zone through the secondary cold head assembly 52, and finally the circulating helium medium is cooled to the liquid helium temperature zone through the throttle valve 9 and sent to the simulated load 10, and the circulating helium medium output from the simulated load 10 is sequentially sent to the cold flow channel of the primary heat exchanger 6; the performance parameters of the primary heat exchanger 6 are calculated according to the temperature, pressure and flowmeter 4 of the hot flow inlet, hot flow outlet, cold flow inlet and cold flow outlet of the primary heat exchanger 6.

[0049] Similarly, in order to facilitate the separate testing of the secondary heat exchanger and the tertiary heat exchanger, the multi-temperature zone low-temperature heat exchanger testing device of this embodiment may also include a first heat exchanger to replace the primary heat exchanger, the hot flow inlet of the first heat exchanger is connected to the output end of the compressor 1, the hot flow outlet of the first heat exchanger is connected to the input end of the primary cold head assembly 51; the cold flow outlet of the first heat exchanger is connected to the input end of the compressor 1. When the secondary heat exchanger is tested separately, the front end of the secondary heat exchanger is connected to the first heat exchanger.

[0050] Similarly, the test device of this embodiment may also include a second heat exchanger to replace the secondary heat exchanger. The hot flow inlet of the second heat exchanger is connected to the output end of the primary cold head assembly 51, and the hot flow outlet of the second heat exchanger is connected to the input end of the secondary cold head assembly 52; the cold flow outlet of the second heat exchanger is connected to the cold flow inlet of the first heat exchanger. When testing the three-stage heat exchanger alone, the first heat exchanger and the second heat exchanger are connected to the front end of the three-stage heat exchanger.

[0051] In addition, the multi-temperature zone low-temperature heat exchanger test device of this embodiment can adjust the circulating medium flow rate according to the heat exchanger, and the compressor 1 is connected between the primary cooling inlet of the primary cold head assembly 51 and the output end of the simulated load 10;

[0052] The test device further includes a main regulating valve 3 and a bypass regulating valve 2. A regulating pipeline is connected between the input end and the output end of the compressor 1. The bypass regulating valve 2 is located on the regulating pipeline, and the main regulating valve 3 is located at the output end of the compressor 1. Further, a flow meter 4 is included, which is located at the output end of the compressor 1 and downstream of the main regulating valve 3. The helium flow rate of the main path is completed by the main regulating valve 3 and the bypass regulating valve 2 to match the design flow rate of the heat exchanger, and the flow meter 4 reads the flow value.

[0053] In other specific implementations of this embodiment, the test device further includes a cold box 11, in which a chamber for accommodating the primary heat exchanger 6, the secondary heat exchanger 7 and the tertiary heat exchanger 8 is provided, and the primary cold head assembly 51, the secondary cold head assembly 52, the throttle valve 9 and the simulated load 10 are all arranged in the cold box 11. In actual design, the chamber in the cold box is set as a vacuum chamber, and except for the compressor, the regulating valve and the flow meter, all others are arranged in the cold box.

[0054] In order to adjust and adapt to different heat exchanger requirements, the simulated load 10 is provided with a first heater; the first-level cold head assembly 51 includes a second heater; the second-level cold head assembly 52 includes a third heater, and the temperature of each temperature zone is adjusted by adjusting the heating power.

[0055] The following describes in detail a multi-temperature zone low-temperature heat exchanger testing method and device of the present application through specific embodiments.

[0056] A multi-temperature zone testing method and device for a low-temperature heat exchanger comprises a compressor 1, regulating valves 2 and 3, a flow meter 4, a GM refrigerator 5 and a cold box.

[0057] The outlet of the compressor 1 is divided into a main route and a bypass route. The main route is connected to the regulating valve 3 and the flow meter 4 in sequence, and then connected to the cold box inlet. The cold box outlet is connected to the compressor 1 inlet; the bypass route is connected to the regulating valve 2 inlet, and the regulating valve 2 outlet is connected to the compressor inlet.

[0058] The cold box is a dotted box in the figure, and the interior of the cold box includes heat exchangers 6 to 8 in different temperature zones, a GM refrigerator primary cold head assembly 51, a GM refrigerator secondary cold head assembly 52, a throttle valve 9, and a simulated load 10.

[0059] The inlet of the cold box is connected to the inlet of the first-stage heat exchanger 6 inside it, the outlet of the first-stage heat exchanger 6 is connected to the inlet of the first-stage cold head assembly 51 of the GM refrigerator, the outlet of the first-stage cold head assembly 51 of the GM refrigerator is connected to the inlet of the second-stage heat exchanger 7, the outlet of the second-stage heat exchanger 7 is connected to the inlet of the second-stage cold head assembly 52 of the GM refrigerator, the outlet of the second-stage cold head assembly 52 of the GM refrigerator is connected to the inlet of the tertiary heat exchanger 8, the outlet of the tertiary heat exchanger 8 is connected to the inlet of the throttle valve 9, the outlet of the throttle valve 9 is connected to the inlet of the simulated load 10, the outlet of the simulated load 10 is connected to the two inlets and outlets of the tertiary heat exchanger 8 and the two inlets and outlets of the secondary heat exchanger 7 in sequence, and finally connected to the outlet of the cold box.

[0060] A multi-temperature zone testing method and device for a low-temperature heat exchanger adopts a compressor 1 as a circulation power, a GM refrigerator 5 as a cold source, and helium as a circulation working medium. Normal temperature helium passes through a refrigerator first-stage component 51 and a refrigerator second-stage component 52 to obtain a liquid nitrogen temperature zone and a liquid hydrogen temperature zone respectively, and finally obtains a liquid helium temperature zone through a throttle valve 9; a three-stage heat exchanger 6-8 is set in the process for heat exchange, and the low-temperature helium is restored to normal temperature to realize a closed cycle; a sensor is set to directly measure the temperature, pressure and other related parameters of the heat exchanger to determine the efficiency and other related parameters of the heat exchanger.

[0061] The multi-temperature zone testing method and device of a low-temperature heat exchanger is a closed circulation system. The specific working process is that the helium is pressurized by the compressor 1 to obtain high-pressure gas and then divided into two paths, the main path and the bypass path. The main path enters the cold box through the regulating valve 3 and the flow meter. The room temperature helium entering the cold box 11 passes through the first-stage heat exchanger 6 to exchange heat with its second path to obtain primary cooling. The helium after primary cooling is cooled twice to 60-80K (liquid nitrogen temperature zone) through the first-stage cold head component of the GM refrigerator; the helium after secondary cooling passes through the second-stage heat exchanger 7 to exchange heat with its second path to obtain tertiary cooling. The helium after tertiary cooling passes through the second-stage cold head component of the GM refrigerator to obtain fourth cooling to 10-15K (liquid hydrogen temperature zone); the helium after fourth cooling passes through the third-stage heat exchanger 8 to exchange heat with its second path to obtain fifth cooling. The helium after fifth cooling is throttled by the throttle valve 9 to obtain a low-pressure fluid of 4.2-4.5K (liquid helium temperature zone). The low-pressure fluid in the liquid helium temperature zone absorbs heat through the simulated load 10 and is heated to 4.6-5K. The fluids in the second and first paths of the third-stage heat exchanger 8, the second-stage heat exchanger 7 and the first-stage heat exchanger 6 are respectively exchanged with each other to recover to normal temperature, and then return to the inlet of the compressor 1 from the outlet of the cold box.

[0062] The helium flow rate of the main path is completed by the cooperation of the main path regulating valve 3 and the bypass regulating valve 2 to match the design flow rate of the heat exchanger, and the flow rate value is read by the flow meter 4.

[0063] The GM refrigerator primary cold head assembly 51, the GM refrigerator secondary cold head assembly 52 and the simulated load 10 are respectively provided with heaters, and the temperature of each temperature zone is adjusted by adjusting the heating power.

[0064] The first, second and third stage heat exchangers 6 to 8 are the heat exchangers to be tested, and their structural types are not fixed, and they can be heat exchangers commonly used in the low temperature field, such as plate type and sleeve type. The working temperature zones of the heat exchangers respectively work in the liquid nitrogen temperature zone, the liquid hydrogen temperature zone and the liquid helium temperature zone. One path of each heat exchanger is a downstream high-pressure hot flow path, and the other path is a countercurrent low-pressure cold flow path. The hot flow path working fluid exchanges heat with the cold flow path working fluid, and the hot flow path working fluid is cooled down, and the cold flow path working fluid is heated up.

[0065] The first and second inlet and outlet of the heat exchanger are both provided with temperature sensors and pressure sensors for measuring the inlet and outlet temperatures and inlet and outlet pressures of the cold and hot fluids of the heat exchanger. The heat exchanger testing method is to measure the inlet and outlet temperatures of the heat exchanger and the system circulation mass flow rate, and calculate the heat exchange efficiency, heat transfer coefficient and pressure drop related parameters of the heat exchanger.

[0066] The present invention uses a compressor as a circulation power and helium as a circulation working medium to form a closed cycle. The entire cycle uses a GM refrigerator as an external cold source, and obtains a minimum temperature of 4.2K through three heat exchanger return air cooling, two refrigerator temperature reduction cooling and throttling refrigeration. This is a refrigeration method. In the process of obtaining 4.2K, the three-stage heat exchanger is respectively in the liquid nitrogen temperature zone, the liquid hydrogen temperature zone, and the liquid helium temperature zone. The system can calculate the relevant performance parameters of the heat exchanger by measuring relevant temperature, pressure, flow and other parameters.

[0067] The system is a closed system, which has the characteristics of simple operation, reliable operation and convenient maintenance compared with the open system.

[0068] Compared with general cryogenic liquid as a cooling source, GM refrigerator has the characteristics of compact structure, convenient operation and high safety.

[0069] A single system can realize three test temperature zones: liquid nitrogen temperature zone, liquid hydrogen temperature zone and liquid helium temperature zone, covering the commonly used temperature zones in the low temperature field with a wide temperature range.

[0070] The system achieves temperature regulation by adjusting the cold source components and the simulated load heating power, making the temperature in each temperature zone adjustable within the range, with high temperature regulation accuracy and good stability.

[0071] This embodiment adopts a closed system with a GM refrigerator as a cold source. The system has the characteristics of simple operation, reliable operation, convenient maintenance, and high safety.

[0072] This embodiment uses a single cold source to achieve three test temperature zones: liquid nitrogen temperature zone, liquid hydrogen temperature zone, and liquid helium temperature zone, covering the commonly used temperature zones in the low temperature field and having a wide temperature range.

[0073] This embodiment adopts a heating countermeasure method to achieve temperature regulation and control of each temperature zone, and the temperature regulation has high precision and good stability.

[0074] This embodiment adds a vacuum system to the system to realize the heat exchanger test in the superfluid helium temperature zone.

[0075] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A multi-temperature zone low-temperature heat exchanger testing device, characterized in that: include: A compressor (1), a primary cold head assembly (51), a secondary cold head assembly (52), a GM refrigerator (5), a throttle valve (9) and a simulated load (10); The compressor (1) is used to provide circulation power for the circulating helium medium; The first-stage cold head assembly (51) has a first-stage cooling inlet and a first-stage cooling outlet, and the first-stage cold head assembly (51) is used to cool the circulating helium medium to a liquid nitrogen temperature range; The secondary cold head assembly (52) has a secondary cooling inlet and a secondary cooling outlet, and the secondary cold head assembly (52) is used to further cool the circulating helium medium after being cooled by the primary cold head assembly (51) to a liquid hydrogen temperature range; The GM refrigerator (5) is used to provide cooling capacity for the primary cold head assembly (51) and the secondary cold head assembly (52); The throttle valve (9) has a three-stage cooling inlet and a three-stage cooling outlet, and is used to further cool the circulating helium medium after being cooled by the secondary cold head assembly (52) to a liquid helium temperature range; The simulated load (10) is connected in series downstream of the third-stage cooling outlet of the throttle valve (9) to provide a load for the test circuit; The circulating helium medium is fed into the hot flow inlet of the first-stage heat exchanger (6), the circulating helium medium output from the hot flow outlet of the first-stage heat exchanger (6) is cooled to a liquid nitrogen temperature zone through the first-stage cold head assembly (51), the circulating helium medium is then cooled to a liquid hydrogen temperature zone through the second-stage cold head assembly (52), and finally the circulating helium medium is cooled to a liquid helium temperature zone through the throttle valve (9) and then fed into the simulated load (10), and the circulating helium medium output from the simulated load (10) is sequentially fed into the cold flow channel of the first-stage heat exchanger (6); The performance parameters of the primary heat exchanger (6) are calculated based on the temperature, pressure and flow rate of the hot flow inlet, hot flow outlet, cold flow inlet and cold flow outlet of the primary heat exchanger (6).

2. The multi-temperature zone low-temperature heat exchanger testing device according to claim 1, characterized in that: The compressor (1) is connected between the primary cooling inlet of the primary cold head assembly (51) and the output end of the simulated load (10); The test device further comprises a main regulating valve (3) and a bypass regulating valve (2); a regulating pipeline is connected between the input end and the output end of the compressor (1); the bypass regulating valve (2) is located on the regulating pipeline, and the main regulating valve (3) is located at the output end of the compressor (1).

3. The multi-temperature zone low-temperature heat exchanger testing device according to claim 2, characterized in that: It also includes a flow meter (4), which is located at the output end of the compressor (1) and downstream of the main regulating valve (3).

4. The multi-temperature zone low-temperature heat exchanger testing device according to claim 1, characterized in that: It also includes a cold box (11), wherein a chamber for accommodating a primary heat exchanger (6), a secondary heat exchanger (7), and a tertiary heat exchanger (8) is provided in the cold box (11), and a primary cold head assembly (51), a secondary cold head assembly (52), a throttle valve (9), and a simulated load (10) are all arranged in the cold box (11).

5. The multi-temperature zone low-temperature heat exchanger testing device according to claim 1, characterized in that: A first heater is provided on the simulated load (10); and / or, the primary cold head assembly (51) comprises a second heater; And / or, the secondary cold head assembly (52) includes a third heater.

6. The multi-temperature zone low-temperature heat exchanger testing device according to claim 1, characterized in that: It also comprises a first heat exchanger, the hot flow inlet of the first heat exchanger being connected to the output end of the compressor (1), the hot flow outlet of the first heat exchanger being connected to the input end of the first-stage cold head assembly (51); and the cold flow outlet of the first heat exchanger being connected to the input end of the compressor (1).

7. The multi-temperature zone low-temperature heat exchanger testing device according to claim 6, characterized in that: It also includes a second heat exchanger, the hot flow inlet of the second heat exchanger is connected to the output end of the first-stage cold head assembly (51), the hot flow outlet of the second heat exchanger is connected to the input end of the second-stage cold head assembly (52); and the cold flow outlet of the second heat exchanger is connected to the cold flow inlet of the first heat exchanger.

8. A multi-temperature zone low-temperature heat exchanger testing method implemented based on the multi-temperature zone low-temperature heat exchanger testing device according to any one of claims 1 to 7, characterized in that: The following steps are involved: The circulating helium medium is fed into the hot flow inlet of the first-stage heat exchanger (6), the circulating helium medium output from the hot flow outlet of the first-stage heat exchanger (6) is cooled to a liquid nitrogen temperature zone through the first-stage cold head assembly (51), the circulating helium medium is then cooled to a liquid hydrogen temperature zone through the second-stage cold head assembly (52), and finally the circulating helium medium is cooled to a liquid helium temperature zone through the throttle valve (9) and then fed into the simulated load (10), and the circulating helium medium output from the simulated load (10) is sequentially fed into the cold flow channel of the first-stage heat exchanger (6); The performance parameters of the primary heat exchanger (6) are calculated based on the temperature, pressure and flow rate of the hot flow inlet, hot flow outlet, cold flow inlet and cold flow outlet of the primary heat exchanger (6).

9. A multi-temperature zone low-temperature heat exchanger testing method implemented based on the multi-temperature zone low-temperature heat exchanger testing device according to any one of claims 1 to 7, characterized in that: The following steps are involved: The circulating helium medium is fed into the hot flow inlet of the first-stage heat exchanger (6); the circulating helium medium output from the hot flow outlet of the first-stage heat exchanger (6) is cooled to a liquid nitrogen temperature zone through the first-stage cold head assembly (51) and then fed into the hot flow inlet of the second-stage heat exchanger (7); the circulating helium medium output from the hot flow outlet of the second-stage heat exchanger (7) is cooled to a liquid hydrogen temperature zone through the second-stage cold head assembly (52); the circulating helium medium is then cooled to a liquid helium temperature zone through the throttle valve (9) and then fed into the simulated load (10); the circulating helium medium output from the simulated load (10) is sequentially fed into the cold flow channels of the second-stage heat exchanger (7) and the first-stage heat exchanger (6); Calculating the performance parameters of the primary heat exchanger (6) based on the temperature, pressure and flow rate of the hot flow inlet, hot flow outlet, cold flow inlet and cold flow outlet of the primary heat exchanger (6); And / or, calculating the performance parameters of the secondary heat exchanger (7) based on the temperature, pressure and flow rate of the hot flow inlet, hot flow outlet, cold flow inlet and cold flow outlet of the secondary heat exchanger (7).

10. A multi-temperature zone low-temperature heat exchanger testing method implemented based on the multi-temperature zone low-temperature heat exchanger testing device according to any one of claims 1 to 7, characterized in that: The following steps are involved: The circulating helium medium is fed into the hot flow inlet of the first-stage heat exchanger (6); the circulating helium medium output from the hot flow outlet of the first-stage heat exchanger (6) is cooled to a liquid nitrogen temperature zone through the first-stage cold head assembly (51) and then fed into the hot flow inlet of the second-stage heat exchanger (7); the circulating helium medium output from the hot flow outlet of the second-stage heat exchanger (7) is cooled to a liquid hydrogen temperature zone through the second-stage cold head assembly (52) and then fed into the hot flow inlet of the third-stage heat exchanger (8); the circulating helium medium output from the hot flow outlet of the third-stage heat exchanger (8) is cooled to a liquid helium temperature zone through the throttle valve (9) and then fed into the simulated load (10); the circulating helium medium output from the simulated load (10) is sequentially fed into the cold flow channels of the third-stage heat exchanger (8), the second-stage heat exchanger (7) and the first-stage heat exchanger (6); Calculate the performance parameters of the primary heat exchanger (6) based on the temperature, pressure and flow meter (4) of the hot flow inlet, hot flow outlet, cold flow inlet and cold flow outlet of the primary heat exchanger (6); and / or, calculating the performance parameters of the secondary heat exchanger (7) based on the temperature, pressure and flow meter (4) of the hot flow inlet, hot flow outlet, cold flow inlet and cold flow outlet of the secondary heat exchanger (7); And / or, calculating the performance parameters of the three-stage heat exchanger (8) based on the temperature, pressure and flow meter (4) of the hot flow inlet, hot flow outlet, cold flow inlet and cold flow outlet of the three-stage heat exchanger (8).

Images