Device for testing heat exchange performance of plate-fin heat exchanger

Abstract

The utility model provides a plate-fin heat exchanger heat exchange performance testing device which comprises a hydrogen source, a vacuum heat insulation container and a liquid nitrogen container, and a heat exchange tube is arranged in the liquid nitrogen container. The plate-fin heat exchanger is arranged in the vacuum heat insulation container and is provided with a cold side heat exchange channel and a hot side heat exchange channel; the two ends of the hot side heat exchange channel are connected with an outlet of the hydrogen source and an inlet of the heat exchange pipe respectively, and the two ends of the cold side heat exchange channel are connected with an outlet of the heat exchange pipe and an emptying pipeline respectively. According to the utility model, the working scene more conforming to the plate-fin heat exchanger in hydrogen liquefaction equipment is constructed, and the heat exchange between the plate-fin heat exchanger and the test environment is reduced through the vacuum heat insulation container, so that the parameter measurement error of the plate-fin heat exchanger is reduced, and guidance is provided for the performance test of various plate-fin heat exchangers which are newly researched and developed subsequently.

Description

Technical Field

[0001] The utility model belongs to the technical field of hydrogen energy utilization equipment, and specifically relates to a heat exchange performance testing device for a plate-fin heat exchanger. Background Art

[0002] Plate-fin heat exchanger is a high-efficiency and energy-saving heat exchanger. It is widely used in cryogenic air separation equipment, natural gas processing and liquefaction equipment, petrochemical product production and tail gas treatment equipment, and large refrigeration equipment. It has the advantages of small size, light weight, large heat exchange area per unit volume, low resistance, and the ability to perform heat exchange of multiple fluids at the same time. It is particularly suitable for the cryogenic engineering industry.

[0003] Heat transfer coefficient and flow resistance are the core index parameters for measuring plate-fin heat exchangers. Testing the heat transfer and resistance of heat exchangers is a common method for measuring heat exchanger performance.

[0004] The cold box where the plate-fin heat exchanger used in the hydrogen liquefaction process is located is a low-temperature vacuum environment, and its operating temperature range is mostly below the liquid nitrogen temperature range (80K). The relevant test and testing equipment in the prior art usually places the heat exchanger in an environment of normal temperature and pressure, and directly measures the temperature and pressure values ​​of the inlet and outlet fluids of the heat exchanger, and then calculates the heat exchange capacity and flow resistance of the heat exchanger.

[0005] However, when the device in the prior art tests the heat exchanger, the external environment will partially transfer heat to the heat exchanger, thereby affecting the accuracy of the heat exchanger performance measurement. In addition, due to the large difference between the heat exchanger test environment and the actual operating conditions in the cold box, the heat exchanger performance parameters obtained from the test need to be further corrected in actual application, which limits the precise application of plate-fin heat exchangers in large-scale hydrogen liquefaction equipment.

[0006] In view of this, the present utility model is proposed. Utility Model Content

[0007] The technical problem to be solved by the utility model is to at least overcome some of the shortcomings of the prior art and provide a plate-fin heat exchanger heat exchange performance testing device, which aims to reduce the error in the measurement of plate-fin heat exchanger parameters by constructing a working scenario that is more in line with the plate-fin heat exchanger in hydrogen liquefaction equipment and reducing the heat exchange between the plate-fin heat exchanger and the test environment through a vacuum insulation container, thereby providing guidance for the performance testing of various newly developed plate-fin heat exchangers.

[0008] In order to solve the above technical problems, the basic concept of the technical solution adopted by the utility model is:

[0009] A plate-fin heat exchanger heat exchange performance testing device comprises a hydrogen source, a vacuum insulation container and a liquid nitrogen container, wherein a heat exchange tube is arranged in the liquid nitrogen container;

[0010] The plate-fin heat exchanger is placed in the vacuum insulation container, and the plate-fin heat exchanger has a cold-side heat exchange channel and a hot-side heat exchange channel;

[0011] The two ends of the hot side heat exchange channel are respectively connected to the outlet of the hydrogen source and the inlet of the heat exchange tube, and the two ends of the cold side heat exchange channel are respectively connected to the outlet of the heat exchange tube and the venting pipeline.

[0012] In some embodiments, the liquid nitrogen container contains liquid nitrogen liquid, and the heat exchange tube is immersed in the liquid nitrogen liquid.

[0013] In some embodiments, the liquid nitrogen container is a liquid nitrogen dewar.

[0014] In some embodiments, the heat exchange tube is a spiral coil.

[0015] In some embodiments, a first valve is provided on the connecting pipeline between the hot-side heat exchange channel and the hydrogen source;

[0016] A second valve is arranged on the vent pipeline.

[0017] In some embodiments, a flow meter for measuring the flow rate of hydrogen entering the plate-fin heat exchanger is provided on the connecting pipeline between the hot-side heat exchange channel and the hydrogen source.

[0018] In some embodiments, a first temperature sensor and a second temperature sensor are respectively disposed at the inlet front end and the outlet rear end of the hot side heat exchange channel;

[0019] A third temperature sensor and a fourth temperature sensor are respectively provided at the front end of the inlet and the rear end of the outlet of the cold side heat exchange channel;

[0020] The first temperature sensor, the second temperature sensor, the third temperature sensor, and the fourth temperature sensor are located in the vacuum insulation container.

[0021] In some embodiments, the inlet front end and the outlet rear end of the hot side heat exchange channel are respectively provided with a first pressure sensor and a second pressure sensor;

[0022] A third pressure sensor and a fourth pressure sensor are respectively provided at the inlet front end and the outlet rear end of the cold side heat exchange channel;

[0023] The first pressure sensor, the second pressure sensor, the third pressure sensor, and the fourth pressure sensor are located outside the vacuum insulation container.

[0024] In some embodiments, a first differential pressure sensor is connected between the inlet front end and the outlet rear end of the hot side heat exchange channel;

[0025] A second differential pressure sensor is connected between the inlet front end and the outlet rear end of the cold side heat exchange channel;

[0026] The first differential pressure sensor and the second differential pressure sensor are located outside the vacuum insulation container.

[0027] In some embodiments, the venting pipeline is connected to a hydrogen recovery device.

[0028] After adopting the above technical scheme, the utility model has the following beneficial effects compared with the prior art.

[0029] 1. The heat exchange performance testing device for plate-fin heat exchangers provided by the utility model is more in line with the working scenario of the plate-fin heat exchanger in hydrogen liquefaction equipment through its structure, and reduces the heat exchange between the plate-fin heat exchanger and the test environment through a vacuum insulation container, thereby reducing the error in the parameter measurement of the plate-fin heat exchanger, and providing guidance for the performance testing of various newly developed plate-fin heat exchangers in the future.

[0030] 2. The heat exchange performance testing device for a plate-fin heat exchanger provided by the utility model arranges a heat exchange tube in a liquid nitrogen container, uses liquid nitrogen to reduce the temperature of hydrogen in the heat exchange tube, and makes the medium in the heat exchange channel on the cold side of the plate-fin heat exchanger be in the liquid nitrogen temperature zone. The device is easy to implement, convenient to operate, flexible to operate, and highly feasible. It can realize the performance test of the actual operating conditions of the plate-fin heat exchanger in a low-temperature laboratory that meets hydrogen safety standards.

[0031] The specific implementation of the utility model is further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings are part of the present invention and are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention, but do not constitute an improper limitation on the present invention. Obviously, the accompanying drawings described below are only some embodiments. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work. In the accompanying drawings:

[0033] Figure 1 It is a structural schematic diagram of a plate-fin heat exchanger heat transfer performance testing device provided according to an exemplary embodiment of the utility model.

[0034] In the figure: 100, testing device;

[0035] 1. Vacuum insulation container; 2. Liquid nitrogen container; 3. Heat exchange tube; 4. First temperature sensor; 5. Second temperature sensor; 6. Third temperature sensor; 7. Fourth temperature sensor; 8. First pressure sensor; 9. Second pressure sensor; 10. Third pressure sensor; 11. Fourth pressure sensor; 12. First differential pressure sensor; 13. Second differential pressure sensor; 14. First valve; 15. Second valve; 16. Flow meter; 17. Plate-fin heat exchanger; 18. Hot side heat exchange channel; 19. Cold side heat exchange channel; 20. Vent pipeline.

[0036] It should be noted that these drawings and textual descriptions are not intended to limit the conceptual scope of the present invention in any way, but rather to illustrate the concept of the present invention for those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solutions and advantages of the embodiments of the utility model clearer, the technical solutions in the embodiments will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. The following embodiments are used to illustrate the utility model but are not used to limit the scope of the utility model.

[0038] In the description of the present invention, it should be noted that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0039] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0040] Figure 1 The structure of a plate-fin heat exchanger heat transfer performance testing device 100 provided according to an exemplary embodiment of the present utility model is shown.

[0041] like Figure 1As shown, the plate-fin heat exchanger heat exchange performance test device 100 includes a hydrogen source, a vacuum insulation container 1 and a liquid nitrogen container 2, wherein the liquid nitrogen container 2 is provided with a heat exchange tube 3. The plate-fin heat exchanger 17 is placed in the vacuum insulation container 1, and the plate-fin heat exchanger 17 has a cold side heat exchange channel 19 and a hot side heat exchange channel 18; the two ends of the hot side heat exchange channel 18 are respectively connected to the outlet of the hydrogen source and the inlet of the heat exchange tube 3, and the two ends of the cold side heat exchange channel 19 are respectively connected to the outlet of the heat exchange tube 3 and the venting pipeline 20.

[0042] When conducting a heat exchange performance test, the plate-fin heat exchanger 17 is arranged in the vacuum insulation container 1, so as to be thermally isolated from the outside world and prevent the plate-fin heat exchanger 17 from exchanging heat with the test environment. The room-temperature hydrogen in the hydrogen source passes through the hot-side heat exchange channel 18 of the plate-fin heat exchanger 17 and enters the heat exchange tube 3 located in the liquid nitrogen container 2 to exchange heat with the liquid nitrogen liquid in the liquid nitrogen container 2. After the temperature of the hydrogen is reduced to the liquid nitrogen temperature zone, it enters the cold-side heat exchange channel 19 of the plate-fin heat exchanger 17 to exchange heat with the room-temperature hydrogen in the hot-side heat exchange channel 18, so that the heat exchange performance of the plate-fin heat exchanger 17 can be tested.

[0043] The hydrogen in the cold side heat exchange channel 19 of the plate-fin heat exchanger 17 can be discharged through the venting pipeline 20 after heat exchange with the hydrogen in the hot side heat exchange channel 18, or can be introduced into a hydrogen recovery device through the venting pipeline 20 for recovery and reuse.

[0044] In the above scheme, by constructing a working scenario that is more in line with the plate-fin heat exchanger 17 in the hydrogen liquefaction equipment and reducing the heat exchange between the plate-fin heat exchanger 17 and the test environment through the vacuum insulation container 1, the error in the parameter measurement of the plate-fin heat exchanger 17 is reduced, and guidance is given to the performance testing of various newly developed plate-fin heat exchangers in the future.

[0045] It should be noted that the absolute pressure in the vacuum insulation container 1 can be set according to the pressure in the actual use environment of the plate-fin heat exchanger 17, and kept consistent with the pressure in the actual use environment of the plate-fin heat exchanger 17. As an example, the absolute pressure in the vacuum insulation container 1 is lower than 1.0×10 -3 Pa.

[0046] Optionally, the vacuum insulation container 1 is connected to a vacuum pump for pumping the absolute pressure in the vacuum insulation container 1 to a preset pressure.

[0047] In some embodiments, the heat exchange tube 3 is immersed in the liquid nitrogen liquid in the liquid nitrogen container 2. Furthermore, the heat exchange tube 3 is a spiral coil, which is conducive to accelerating the cooling speed of the hydrogen. Optionally, the liquid nitrogen container 2 is a liquid nitrogen dewar. The use of a liquid nitrogen dewar to contain liquid nitrogen liquid is safer, which is conducive to improving the safety of the plate-fin heat exchanger heat exchange performance test device 100, and can realize the performance test of the actual operating conditions of the plate-fin heat exchanger 17 in a low-temperature laboratory that meets the hydrogen safety standards.

[0048] In some embodiments, a first valve 14 is provided on the connecting pipeline between the hot side heat exchange channel 18 and the hydrogen source, which is used to control the entry of hydrogen into the hot side heat exchange channel 18 of the plate-fin heat exchanger 17; a second valve 15 is provided on the vent pipeline 20, which is used to control the flow of hydrogen out of the cold side heat exchange channel 19 of the plate-fin heat exchanger 17.

[0049] Optionally, the first valve 14 and the second valve 15 are manual valves, which is beneficial to reducing the test cost of the plate-fin heat exchanger heat exchange performance testing device 100 .

[0050] In some embodiments, a flow meter 16 for measuring the flow rate of hydrogen entering the plate-fin heat exchanger 17 is provided on the connecting pipeline between the hot side heat exchange channel 18 and the hydrogen source. The flow meter 16 can be a differential pressure flow meter, a vortex flow meter, etc. commonly used in the art, and the utility model does not limit it.

[0051] The inlet front end and outlet rear end of the hot side heat exchange channel 18 are respectively provided with a first temperature sensor 4 and a second temperature sensor 5, which are used to measure the hydrogen temperature at the inlet and outlet of the hot side heat exchange channel 18 of the plate-fin heat exchanger 17; the inlet front end and outlet rear end of the cold side heat exchange channel 19 are respectively provided with a third temperature sensor 6 and a fourth temperature sensor 7, which are used to measure the hydrogen temperature at the inlet and outlet of the cold side heat exchange channel 19 of the plate-fin heat exchanger 17. The first temperature sensor 4 and the second temperature sensor 5, the third temperature sensor 6 and the fourth temperature sensor 7 are all located in the vacuum insulation container 1 to prevent the hydrogen temperature measured by the temperature sensor from being affected by the test environment temperature. Optionally, the first temperature sensor 4, the second temperature sensor 5, the third temperature sensor 6 and the fourth temperature sensor 7 can adopt a contact structure, such as a thermistor type temperature sensor.

[0052] The inlet front end and outlet rear end of the hot side heat exchange channel 18 are respectively provided with a first pressure sensor 8 and a second pressure sensor 9, which are used to measure the hydrogen pressure at the inlet and outlet of the hot side heat exchange channel 18 of the plate-fin heat exchanger 17; the inlet front end and outlet rear end of the cold side heat exchange channel 19 are respectively provided with a third pressure sensor 10 and a fourth pressure sensor 11, which are used to measure the hydrogen pressure at the inlet and outlet of the cold side heat exchange channel 19 of the plate-fin heat exchanger 17. The first pressure sensor 8 and the second pressure sensor 9, the third pressure sensor 10 and the fourth pressure sensor 11 are located outside the vacuum insulation container 1 to prevent the hydrogen pressure measured by the pressure sensor from being affected by the vacuum environment in the vacuum insulation container 1. Optionally, the first pressure sensor 8, the second pressure sensor 9, the third pressure sensor 10 and the fourth pressure sensor 11 can adopt structures commonly used in the field such as piezoresistive and piezoelectric.

[0053] A first differential pressure sensor 12 is connected between the inlet front end and the outlet rear end of the hot side heat exchange channel 18, which is used to measure the hydrogen pressure difference between the inlet and outlet of the hot side heat exchange channel 18 of the plate-fin heat exchanger 17; a second differential pressure sensor 13 is connected between the inlet front end and the outlet rear end of the cold side heat exchange channel 19, which is used to measure the hydrogen pressure difference between the inlet and outlet of the cold side heat exchange channel 19 of the plate-fin heat exchanger 17. The first differential pressure sensor 12 and the second differential pressure sensor 13 are located outside the vacuum insulation container 1 to prevent the hydrogen pressure difference measured by the differential pressure sensor from being affected by the vacuum environment in the vacuum insulation container 1. Optionally, the first differential pressure sensor 12 and the second differential pressure sensor 13 can adopt differential capacitance and differential resistance structures commonly used in the art.

[0054] The following is an introduction to the process of conducting a heat exchange performance test using the plate-fin heat exchanger heat exchange performance test device 100 described above.

[0055] It should be noted that before conducting a heat exchange performance test, the fin length l, height h, thickness s, pitch δ and heat exchange area S of the plate-fin heat exchanger 17 should be measured first, and then the plate-fin heat exchanger 17 should be placed in the vacuum insulation container 1.

[0056] Step 1, open the first valve 14 and the second valve 15, and introduce hydrogen to perform gas purge and replacement on the testing device 100, and then close the first valve 14 and the second valve 15 after completion.

[0057] The specific steps are as follows: before purging and replacing, ensure that the first valve 14 and the second valve 15 are in a closed state; then open the first valve 14 at the gas pipeline inlet, introduce hydrogen, and close the first valve 14 after reaching the set pressure. After the pressure stabilizes, connect the exhaust port of the venting pipeline 20 to a vacuum pump, open the second valve 15, and use the vacuum pump to evacuate the test device 100. Repeat the above operation 3 to 8 times. After the gas replacement is completed, close the first valve 14 and the second valve 15.

[0058] Step 2: Use a vacuum pump to pump the pressure in the vacuum insulation container 1 to below the preset pressure (the actual operating environment pressure of the plate-fin heat exchanger 17) and maintain the pressure; inject low-temperature liquid nitrogen liquid into the liquid nitrogen container 2 to ensure that the liquid level of the low-temperature liquid nitrogen liquid exceeds the top of the heat exchange tube 3.

[0059] Step 3, open the first valve 14 and the second valve 15 to introduce hydrogen into the hot side heat exchange channel 18 and the cold side heat exchange channel 19 of the plate-fin heat exchanger 17, and adjust the flow rate of hydrogen in the pipeline by adjusting the opening of the second valve 15.

[0060] Step 4, after the readings of the first pressure sensor 8, the second pressure sensor 9, the third pressure sensor 10, the fourth pressure sensor 11, the first differential pressure sensor 12, the second differential pressure sensor 13, the first temperature sensor 4, the second temperature sensor 5, the third temperature sensor 6, the fourth temperature sensor 7, and the flow meter 16 are stable, record the inlet pressure P11, inlet temperature T11, and outlet pressure P12, and outlet temperature T12 of the heat exchange channel 18 on the hot side of the plate-fin heat exchanger 17; record the inlet pressure P21, inlet temperature T21, and outlet pressure P22, and outlet temperature T22 of the heat exchange channel 19 on the cold side of the plate-fin heat exchanger 17; record the inlet and outlet pressure difference ΔP1 of the heat exchange channel 18 on the hot side of the plate-fin heat exchanger 17, and the inlet and outlet pressure difference ΔP2 of the heat exchange channel 19 on the cold side of the plate-fin heat exchanger 17; and the flow rate Q in the gas pipeline.

[0061] Step 5, according to the inlet pressure P11 and the inlet temperature T11 of the heat exchange channel 18 on the hot side of the plate-fin heat exchanger 17, the enthalpy value of the hydrogen at the inlet of the heat exchange channel 18 on the hot side of the plate-fin heat exchanger 17 is obtained, and according to the outlet pressure P12 and the outlet temperature T12 of the heat exchange channel 18 on the hot side of the plate-fin heat exchanger 17, the enthalpy value of the hydrogen at the outlet of the heat exchange channel 18 on the hot side of the plate-fin heat exchanger 17 is obtained, the heat exchange power of the plate-fin heat exchanger 17 is calculated, and the heat flow q per unit area of ​​the plate-fin heat exchanger 17 is obtained according to the heat exchange area S of the plate-fin heat exchanger 17. The hydraulic diameter d of the plate-fin heat exchanger 17 is calculated according to the length l, height h, thickness s and pitch δ of the fins of the plate-fin heat exchanger 17; the logarithmic mean temperature difference ΔT between the hot-side heat exchange channel 18 and the cold-side heat exchange channel 19 of the plate-fin heat exchanger 17 is calculated according to the inlet and outlet temperatures of the plate-fin heat exchanger 17; the dynamic viscosity and specific heat capacity of hydrogen at the inlet and outlet of the hot-side heat exchange channel 18 of the plate-fin heat exchanger 17 are obtained according to the inlet pressure P11 and the inlet temperature T11 of the hot-side heat exchange channel 18 of the plate-fin heat exchanger 17 and the outlet pressure P12 and the outlet temperature T12 of the hot-side heat exchange channel 18 of the plate-fin heat exchanger 17; and the average dynamic viscosity μ and the average specific heat capacity cp during the heat exchange process are calculated.

[0062] According to the formula j = Nu / (Re·Pr 1 / 3 )=(q·d) / (ΔT·μ·cp) to calculate the Colburn heat transfer factor j, which is used to describe the heat transfer performance characteristics of the plate-fin heat exchanger 17.

[0063] The mass flow rate per unit flow area GA of the plate-fin heat exchanger 17 is obtained according to the length l, height h, thickness s, pitch δ of the fins of the plate-fin heat exchanger 17 and the flow rate Q in the heat exchanger. The density of hydrogen at the inlet and outlet of the heat exchange channel 18 on the hot side of the plate-fin heat exchanger 17 is obtained according to the inlet pressure P11 and inlet temperature T11 of the heat exchange channel 18 on the hot side of the plate-fin heat exchanger 17, the outlet pressure P12 and outlet temperature T12 of the heat exchange channel 18 on the hot side of the plate-fin heat exchanger 17, and the average density ρf in the heat exchange process is calculated. According to the formula f=ρf·d·ΔP1 / (2·GA 2 l) Calculate the Fanning friction factor f, which is used to describe the flow resistance characteristics of the plate-fin heat exchanger 17.

[0064] According to formula F 热 =j / f 1 / 3 The heat exchange enhancement factor of the hot-side heat exchange channel 18 of the plate-fin heat exchanger 17 is calculated to evaluate the comprehensive heat exchange performance of the plate-fin heat exchanger 17 .

[0065] In the above step 5, the heat transfer enhancement factor is calculated using the parameters of the heat exchange channel 18 on the hot side of the plate-fin heat exchanger 17. To ensure the accuracy of the measurement, the heat transfer enhancement factor can also be calculated using the parameters of the heat exchange channel 19 on the cold side of the plate-fin heat exchanger 17 using the method in the above step 5.

[0066] Specifically, the enthalpy value of hydrogen at the inlet of the cold side heat exchange channel 19 of the plate-fin heat exchanger 17 is obtained according to the inlet pressure P21 and the inlet temperature T21 of the cold side heat exchange channel 19 of the plate-fin heat exchanger 17, and the enthalpy value of hydrogen at the outlet of the cold side heat exchange channel 19 of the plate-fin heat exchanger 17 is obtained according to the outlet pressure P22 and the outlet temperature T22 of the cold side heat exchange channel 19 of the plate-fin heat exchanger 17. The heat exchange power of the plate-fin heat exchanger 17 is calculated, and the heat flow q per unit area of ​​the plate-fin heat exchanger 17 is obtained according to the heat exchange area S of the plate-fin heat exchanger 17. The hydraulic diameter d of the plate-fin heat exchanger 17 is obtained according to the length l, height h, thickness s and pitch δ of the fins of the plate-fin heat exchanger 17; the logarithmic mean temperature difference ΔT between the hot-side heat exchange channel 18 and the cold-side heat exchange channel 19 of the plate-fin heat exchanger 17 is obtained according to the temperatures at the inlet and outlet of the plate-fin heat exchanger 17; the dynamic viscosity and specific heat capacity of hydrogen at the inlet and outlet of the cold-side heat exchange channel 19 of the plate-fin heat exchanger 17 are obtained according to the inlet pressure P21 and the inlet temperature T21 of the cold-side heat exchange channel 19 of the plate-fin heat exchanger 17 and the outlet pressure P22 and the outlet temperature T22 of the cold-side heat exchange channel 19 of the plate-fin heat exchanger 17; and the average dynamic viscosity μ and the average specific heat capacity cp during the heat exchange process are calculated.

[0067] According to the formula j = Nu / (Re·Pr 1 / 3 )=(q·d) / (ΔT·μ·cp) to calculate the Colburn heat transfer factor j, which is used to describe the heat transfer performance characteristics of the plate-fin heat exchanger 17.

[0068] The mass flow rate per unit flow area GA of the plate-fin heat exchanger 17 is obtained according to the length l, height h, thickness s, pitch δ of the fins of the plate-fin heat exchanger 17 and the flow rate Q in the heat exchanger. The density of hydrogen at the inlet and outlet of the cold side heat exchange channel 19 of the plate-fin heat exchanger 17 is obtained according to the inlet pressure P21 and inlet temperature T21 of the cold side heat exchange channel 19 of the plate-fin heat exchanger 17, the outlet pressure P22 and outlet temperature T22 of the cold side heat exchange channel 19 of the plate-fin heat exchanger 17. The average density ρf in the heat exchange process is calculated according to the formula f=ρf·d·ΔP2 / (2·GA 2 l) Calculate the Fanning friction factor f, which is used to describe the flow resistance characteristics of the plate-fin heat exchanger 17.

[0069] According to formula F 冷 =j / f 1 / 3The heat exchange enhancement factor of the cold-side heat exchange channel 19 of the plate-fin heat exchanger 17 is calculated to evaluate the comprehensive heat exchange performance of the plate-fin heat exchanger 17 .

[0070] Calculate F 热 and F 冷 Afterwards, according to F 热 and F 冷 The value between 1 and 2 determines the accuracy of the measurement result. If the difference between the two is large, the plate-fin heat exchanger 17 needs to be measured again.

[0071] In addition, the plate-fin heat exchanger 17 may be measured multiple times to eliminate random errors.

[0072] The above is only a preferred embodiment of the present invention, and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the present invention can make some changes or modifications to equivalent embodiments of equivalent changes using the above-mentioned technical contents without departing from the scope of the technical solution of the present invention. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the present invention.

Claims

1. A plate-fin heat exchanger heat exchange performance testing device, characterized in that: It comprises a hydrogen source, a vacuum insulation container and a liquid nitrogen container, wherein the liquid nitrogen container is provided with a heat exchange tube; The plate-fin heat exchanger is placed in the vacuum insulation container, and the plate-fin heat exchanger has a cold-side heat exchange channel and a hot-side heat exchange channel; The two ends of the hot side heat exchange channel are respectively connected to the outlet of the hydrogen source and the inlet of the heat exchange tube, and the two ends of the cold side heat exchange channel are respectively connected to the outlet of the heat exchange tube and the venting pipeline.

2. The plate-fin heat exchanger heat exchange performance testing device according to claim 1, characterized in that: The liquid nitrogen container contains liquid nitrogen liquid, and the heat exchange tube is immersed in the liquid nitrogen liquid.

3. The plate-fin heat exchanger heat exchange performance testing device according to claim 2, characterized in that: The liquid nitrogen container is a liquid nitrogen Dewar.

4. The plate-fin heat exchanger heat exchange performance testing device according to claim 2, characterized in that: The heat exchange tube is a spiral coil.

5. The plate-fin heat exchanger heat exchange performance testing device according to any one of claims 1 to 4, characterized in that: A first valve is provided on the connecting pipeline between the hot side heat exchange channel and the hydrogen source; A second valve is arranged on the vent pipeline.

6. The plate-fin heat exchanger heat exchange performance testing device according to any one of claims 1 to 4, characterized in that: A flow meter for measuring the flow rate of hydrogen entering the plate-fin heat exchanger is arranged on the connecting pipeline between the hot-side heat exchange channel and the hydrogen source.

7. The plate-fin heat exchanger heat exchange performance testing device according to any one of claims 1 to 4, characterized in that: The inlet front end and the outlet rear end of the hot side heat exchange channel are respectively provided with a first temperature sensor and a second temperature sensor; A third temperature sensor and a fourth temperature sensor are respectively provided at the front end of the inlet and the rear end of the outlet of the cold side heat exchange channel; The first temperature sensor, the second temperature sensor, the third temperature sensor, and the fourth temperature sensor are located in the vacuum insulation container.

8. The plate-fin heat exchanger heat exchange performance testing device according to any one of claims 1 to 4, characterized in that: The inlet front end and the outlet rear end of the hot side heat exchange channel are respectively provided with a first pressure sensor and a second pressure sensor; A third pressure sensor and a fourth pressure sensor are respectively provided at the inlet front end and the outlet rear end of the cold side heat exchange channel; The first pressure sensor, the second pressure sensor, the third pressure sensor, and the fourth pressure sensor are located outside the vacuum insulation container.

9. The plate-fin heat exchanger heat exchange performance testing device according to any one of claims 1 to 4, characterized in that: A first differential pressure sensor is connected between the inlet front end and the outlet rear end of the hot side heat exchange channel; A second differential pressure sensor is connected between the inlet front end and the outlet rear end of the cold side heat exchange channel; The first differential pressure sensor and the second differential pressure sensor are located outside the vacuum insulation container.

10. The plate-fin heat exchanger heat exchange performance testing device according to any one of claims 1 to 4, characterized in that: The venting pipeline is connected with a hydrogen recovery device.

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