Liquid hydrogen medium active exhaust cooling test system and method

Abstract

The invention discloses a liquid hydrogen medium active exhaust cooling test system and method. The system comprises a vacuum module, a liquid hydrogen storage box module, a gas replacement and filling module, an exhaust cooling test module, a helium pressurization module, a leakage and safe discharge module, an external heat flow simulation module and a measurement and control module. According to the scheme, on the basis of simulating the external vacuum environment, the test of active exhaust cooling of the liquid hydrogen medium space is achieved through gas replacement, filling, testing and the like, and compared with the prior art, the liquid hydrogen medium space active exhaust cooling device is comprehensive in function.

Description

Technical Field

[0001] This invention belongs to the field of liquid hydrogen propellant space application technology, and particularly relates to an active exhaust cooling test system and method for liquid hydrogen medium. Background Technology

[0002] Cryogenic propellants, due to their high specific impulse and non-toxic, non-polluting nature, are the preferred propellants for low Earth orbit upper stages, lunar orbit vehicles, Mars probes, and deeper space exploration vehicles. The use of cryogenic propellants can significantly improve the payload capacity of low Earth orbit upper stages, increase the effective payload mass of lunar and Mars deep space vehicles, and extend the on-orbit lifespan of spacecraft. However, because cryogenic propellants have extremely low boiling points (liquid hydrogen approximately -253°C, liquid oxygen approximately -183°C, liquid methane approximately -161°C) and relatively low latent heat of vaporization, they will experience temperature increases or evaporation under the complex and harsh thermal environment created by solar radiation, planetary radiation, and deep space background radiation in orbit. Simultaneously, the microgravity environment in space causes uncertainty in the gas-liquid positions, exacerbating thermal stratification within the cryogenic tank, posing challenges to the pressure control, temperature control, and on-orbit application of cryogenic propellants. Summary of the Invention

[0003] The technical problem solved by this invention is to overcome the shortcomings of the prior art and provide an active exhaust cooling test system and method for liquid hydrogen medium. It has functions such as vacuum function, liquid hydrogen tank gas replacement and filling function, exhaust cooling test function, pressurization function, venting and safe discharge function, external heat flow simulation function, measurement and control function, etc. It can realize the replacement and filling of liquid hydrogen tank under vacuum conditions, and conduct test experiments on the exhaust cooling characteristics of liquid hydrogen medium in the tank under different pressure control zones.

[0004] To address the aforementioned technical problems, this invention discloses an active exhaust cooling test system for liquid hydrogen media, comprising:

[0005] Vacuum module, used to obtain and maintain the vacuum environment of the test system;

[0006] Liquid hydrogen storage tank module, used for liquid level measurement during liquid hydrogen refilling and thermal stratification measurement during storage;

[0007] The gas replacement and filling module is used for nitrogen and hydrogen replacement before liquid hydrogen medium filling, and for liquid hydrogen medium filling after the replacement is completed.

[0008] The exhaust cooling test module is used to adjust different exhaust flow rates during exhaust cooling tests to verify the effect of different exhaust flow rates on the rate of temperature reduction of liquid hydrogen medium.

[0009] The helium pressurization module is used to pressurize the liquid hydrogen storage tank.

[0010] The venting and safety discharge module is used for the discharge of liquid hydrogen during normal testing; and for emergency discharge and depressurization of liquid hydrogen in case of failure.

[0011] The external heat flow simulation module is used to regulate the external heat flow.

[0012] The measurement and control module is used to acquire temperature, pressure, and flow data; and to control the vacuum module, liquid hydrogen storage tank module, gas replacement and filling module, exhaust cooling test module, helium pressurization module, venting and safety discharge module, and external heat flow simulation module.

[0013] In the above-mentioned liquid hydrogen medium active exhaust cooling test system, the vacuum module includes: vacuum tank, vacuum tank support, vacuum sealing flange, lifting ring, lifting tool, explosion-proof vacuum unit, vacuum pumping pipeline, main vacuum silicon, backup vacuum silicon, vacuum tank explosion-proof plate, manual valve A, nitrogen positive pressure explosion-proof box A, vacuum flange A, vacuum flange B, vacuum connector and vacuum flange C.

[0014] The vacuum tank has a two-part structure, which is connected by a vacuum sealing flange.

[0015] The vacuum tank is mounted on a vacuum tank support.

[0016] The lifting ring and the vacuum tank explosion-proof plate are installed on the top of the vacuum tank; during disassembly and assembly, the lifting ring is connected to the lifting tool to lift the upper part of the vacuum tank structure.

[0017] Vacuum flange A, vacuum flange B, vacuum connector and vacuum flange C are respectively installed on the side wall of the vacuum tank;

[0018] The main vacuum silicon and the backup vacuum silicon are placed in nitrogen positive pressure explosion-proof box A and connected to the side wall of the vacuum tank through pipelines.

[0019] A manual valve A is installed between the main vacuum silicon and the backup vacuum silicon and the vacuum tank;

[0020] The explosion-proof vacuum unit is connected to the main vacuum silicon and backup vacuum silicon via vacuum piping, and is used to measure the vacuum level of the vacuum tank.

[0021] In the above-mentioned liquid hydrogen medium active exhaust cooling test system, the liquid hydrogen storage tank module includes: liquid hydrogen storage tank, composite insulation layer, low thermal conductivity support, storage tank temperature sensor group, storage tank pressure sensor, cryogenic connector, cryogenic flange A, ramp baffle, cryogenic flange B and cryogenic flange C.

[0022] A liquid hydrogen storage tank is used for storing liquid hydrogen; the liquid hydrogen storage tank is placed in a vacuum tank by a low thermal conductivity support; the outside of the liquid hydrogen storage tank is covered with a composite insulation layer.

[0023] The cryogenic connector is installed on the top of the liquid hydrogen storage tank; the tank temperature sensor group is arranged inside the liquid hydrogen storage tank and is connected to the cryogenic connector through wires to realize the measurement of the temperature of the liquid hydrogen medium and the determination of the filling level;

[0024] Cryogenic flange A and cryogenic flange B are installed on top of the liquid hydrogen storage tank;

[0025] The ramp-type baffle is installed inside the liquid hydrogen storage tank, located below the cryogenic flange A, at a 45° angle to the axis of the liquid hydrogen storage tank, to prevent the liquid from rushing directly to the liquid surface during filling;

[0026] Cryogenic flange C is installed at the bottom of the liquid hydrogen storage tank;

[0027] The tank pressure sensor is installed on top of the liquid hydrogen tank to measure the pressure of the liquid hydrogen tank.

[0028] In the above-mentioned liquid hydrogen medium active exhaust and cooling test system, the gas replacement and filling module includes: nitrogen positive pressure explosion-proof box B, nitrogen replacement pipeline, manual valve B, liquid hydrogen filling pipeline, manual valve C, cryogenic solenoid valve, hydrogen replacement pipeline, manual valve D, filter, liquid safety valve, high-altitude discharge pipe, manual valve E, ambient temperature solenoid valve A, filling line pressure sensor, filling line temperature sensor, ambient temperature solenoid valve B, and gas composition analyzer;

[0029] One end of the nitrogen replacement pipeline is connected to a nitrogen source, and the other end is connected in sequence to a normal temperature solenoid valve A, a manual valve B, and then connected to the liquid hydrogen filling pipeline after being combined with the hydrogen replacement pipeline.

[0030] One end of the hydrogen replacement pipeline is connected to the hydrogen source, and the other end is connected in sequence to manual valve D, ambient temperature solenoid valve B, and then connected to the liquid hydrogen filling pipeline after being combined with the nitrogen replacement pipeline.

[0031] One end of the liquid hydrogen filling pipeline is connected to the liquid hydrogen source, and the other end is connected in sequence to the filter, manual valve C, liquid circuit safety valve, and cryogenic solenoid valve. Then it enters the vacuum tank through vacuum flange B, and then enters the liquid hydrogen storage tank through cryogenic flange A.

[0032] The filling line pressure sensor and filling line temperature sensor are installed on the liquid hydrogen filling line, located between the filter and manual valve C;

[0033] The gas composition analyzer is placed in a nitrogen positive pressure explosion-proof box B and connected to a high-altitude exhaust pipe via a pipeline; a manual valve E is installed on the connecting pipeline between the gas composition analyzer and the high-altitude exhaust pipe.

[0034] In the above-mentioned liquid hydrogen medium active exhaust cooling test system, the exhaust cooling test module includes: exhaust main pipeline, ambient temperature vaporizer, ambient temperature solenoid valve C, ambient temperature solenoid valve D, ambient temperature solenoid valve E, ambient temperature solenoid valve F, throttle valve A, throttle valve B, throttle valve C, throttle valve D, electric regulating valve, gas mass flow meter A, gas mass flow meter B, exhaust manifold A, manual valve F, gas vacuum pipeline, exhaust line front pressure sensor, exhaust line front temperature sensor, exhaust line rear pressure sensor, exhaust line rear temperature sensor, exhaust cooling main pipeline and exhaust manifold B;

[0035] One end of the exhaust main pipeline enters the liquid hydrogen storage tank via cryogenic flange B, and the other end exits the vacuum tank via vacuum flange C. It is then connected in sequence to the gas vacuum pipeline, ambient air vaporizer, exhaust cooling main pipeline, exhaust line temperature sensor, exhaust line pressure sensor, and manual valve F.

[0036] The exhaust cooling main pipe is divided into four branches: the first branch connects to the ambient temperature solenoid valve C and the throttle valve D in sequence; the second branch connects to the ambient temperature solenoid valve D and the throttle valve C in sequence; the third branch connects to the ambient temperature solenoid valve E and the throttle valve B in sequence; the fourth branch connects to the ambient temperature solenoid valve F, the throttle valve A, and the electric regulating valve in sequence; the first and second branches are connected in parallel and then converged to one end of the exhaust manifold A, and the other end of the exhaust manifold A is connected to one end of the gas mass flow meter B; the third and fourth branches are connected in parallel and then converged to one end of the exhaust manifold B, and the other end of the exhaust manifold B is connected to one end of the gas mass flow meter A; the other end of the gas mass flow meter B and the other end of the gas mass flow meter A are then connected in sequence to the exhaust pressure sensor, the exhaust temperature sensor, and the high-altitude discharge pipe.

[0037] In the above-mentioned liquid hydrogen medium active exhaust cooling test system, the helium pressurization module includes: a normal temperature solenoid valve G, a manual valve G, a flow controller, a pressurization circuit pressure sensor, a pressurization circuit temperature sensor, and a helium pipeline.

[0038] One end of the helium pipeline is connected to a helium source, and the other end is connected in sequence to a room temperature solenoid valve G, a pressure sensor for the booster circuit, a temperature sensor for the booster circuit, a manual valve G, and a flow controller before being connected to a liquid hydrogen filling pipeline.

[0039] In the above-mentioned liquid hydrogen medium active exhaust and cooling test system, the venting and safe discharge module includes: manual valve H, ambient temperature solenoid valve H, tank venting pipeline, ambient temperature solenoid valve I, manual valve I, main gas line safety valve, backup gas line safety valve, main gas line explosion-proof plate, backup gas line explosion-proof plate, three-phase plug valve, safe discharge pipe, nitrogen purging pipeline, ambient temperature solenoid valve J, manual valve J, liquid vacuum pipeline, manual valve K, gas venting pipe and pre-cooling discharge pipe;

[0040] One end of the inlet venting pipeline is connected to the liquid hydrogen storage tank via cryogenic flange C; the other end is connected to the liquid vacuum pipeline, ambient temperature vaporizer, gas venting pipeline, and high-altitude discharge pipeline in sequence after exiting the vacuum tank via vacuum flange C; manual valve I and ambient temperature solenoid valve I are installed on the gas venting pipeline in sequence.

[0041] One end of the safety discharge pipe is connected to the exhaust cooling main pipe, and the other end is connected to the high-altitude discharge pipe; the safety discharge pipe is equipped with a manual valve K, a three-phase plug valve, a main air circuit safety valve, and a backup air circuit safety valve in sequence; the main air circuit safety valve and the backup air circuit safety valve are connected in parallel, the main air circuit explosion-proof plate is connected in parallel with the main air circuit safety valve, and the backup air circuit explosion-proof plate is connected in parallel with the backup air circuit safety valve;

[0042] One end of the nitrogen purging pipeline is connected to a nitrogen source, and the other end is connected in sequence to a normal temperature solenoid valve J and a manual valve J, and enters the vacuum tank through the vacuum flange B;

[0043] One end of the precooling discharge pipe is connected to the exhaust cooling main pipe, and the other end is connected to the high-altitude discharge pipe; a manual valve H and a normal temperature solenoid valve H are installed on the precooling discharge pipe in sequence.

[0044] In the above-mentioned liquid hydrogen medium active exhaust cooling test system, the external heat flow simulation module includes: constant temperature water tank, circulating pump, radiation screen, nitrogen positive pressure explosion-proof box C, manual valve L, manual valve M, heat sink circulation inlet pipe, radiation screen coil, heat sink circulation outlet pipe, heat sink inlet temperature sensor and heat sink outlet temperature sensor.

[0045] The radiation screen is installed on the inner wall of the upper part of the vacuum tank; the radiation screen coil is installed on the radiation screen;

[0046] It is positioned between the liquid hydrogen storage tank and the vacuum tank;

[0047] The constant temperature water tank is connected to the circulating pump and placed inside a nitrogen positive pressure explosion-proof box C;

[0048] One end of the heat sink circulation inlet pipe is connected to the circulation pump, and the other end enters the vacuum tank through vacuum flange A and is connected to the radiation screen coil on the radiation screen; then it exits the vacuum tank through vacuum flange A and is connected to one end of the heat sink circulation outlet pipe; the other end of the heat sink circulation outlet pipe is connected to the constant temperature water tank to form a circulation loop.

[0049] A manual valve L and a heat sink inlet temperature sensor are installed sequentially on the heat sink circulation inlet pipe, and a manual valve M and a heat sink outlet temperature sensor are installed sequentially on the heat sink circulation outlet pipe.

[0050] In the above-mentioned liquid hydrogen medium active exhaust cooling test system, the measurement and control module includes: a data acquisition instrument, a PLC controller, an Ethernet switch, a measurement and control computer, and a regulated power supply;

[0051] The monitoring and control computer is located in the space at the far end of the vacuum tank;

[0052] The data acquisition unit, PLC controller, and Ethernet switch are placed inside a nitrogen positive pressure explosion-proof box C;

[0053] The measurement and control computer is connected to the data acquisition instrument and the PLC controller via an Ethernet switch;

[0054] The regulated power supply is connected to the data acquisition instrument, PLC controller, Ethernet switch and measurement and control computer respectively, providing power to the data acquisition instrument, PLC controller, Ethernet switch and measurement and control computer.

[0055] Accordingly, the present invention also discloses a test method for active exhaust cooling of liquid hydrogen medium, comprising:

[0056] An active venting and cooling test system for liquid hydrogen was constructed. The active venting and cooling test system for liquid hydrogen includes: a vacuum module, a liquid hydrogen storage tank module, a gas replacement and filling module, a venting and cooling test module, a helium pressurization module, and a leakage and safe discharge module.

[0057] Pre-test inspection of the active exhaust cooling test system for liquid hydrogen medium;

[0058] The vacuum module is in operation, performing vacuuming.

[0059] Nitrogen replacement, hydrogen replacement, and liquid hydrogen medium injection are performed sequentially through the gas replacement and injection modules.

[0060] The external heat flow is regulated and the liquid hydrogen storage tank is pressurized by the external heat flow simulation module and the helium pressurization module.

[0061] The exhaust cooling test module allows for the adjustment of different exhaust flow rates to conduct exhaust cooling tests and verify the effect of different exhaust flow rates on the rate of temperature reduction of liquid hydrogen medium.

[0062] After the exhaust cooling test is completed, the liquid hydrogen medium is discharged through the venting and safe discharge module;

[0063] The vacuum module was shut down, and the experiment was completed.

[0064] The present invention has the following advantages:

[0065] This invention discloses a liquid hydrogen medium active exhaust cooling test system and method. Based on simulating an external vacuum environment, the active exhaust cooling of liquid hydrogen medium is tested through gas replacement, injection, and testing. Attached Figure Description

[0066] Figure 1 This is a schematic diagram of the structure of an active exhaust cooling test system for liquid hydrogen medium in an embodiment of the present invention. Detailed Implementation

[0067] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments disclosed in the present invention will be described in further detail below with reference to the accompanying drawings.

[0068] One of the core ideas of this invention is that existing technical solutions do not involve experimental functions for controlling the temperature of liquid hydrogen through active exhaust cooling, and cannot conduct experimental research on exhaust cooling under different exhaust pressures, exhaust strategies, etc. To solve the above problems, this invention discloses an active exhaust cooling experimental system for liquid hydrogen.

[0069] Reference Figure 1 In this embodiment, the liquid hydrogen medium active exhaust cooling test system includes:

[0070] Vacuum module, used to obtain and maintain the vacuum environment of the test system.

[0071] The liquid hydrogen storage tank module is used for liquid level measurement during liquid hydrogen refueling and thermal stratification measurement during storage.

[0072] The gas replacement and filling module is used for nitrogen replacement and hydrogen replacement before liquid hydrogen medium filling; and for liquid hydrogen medium filling after the replacement is completed.

[0073] The exhaust cooling test module is used to adjust different exhaust flow rates during exhaust cooling tests to verify the effect of different exhaust flow rates on the rate of temperature reduction of liquid hydrogen medium.

[0074] The helium pressurization module is used to pressurize the liquid hydrogen storage tank.

[0075] The venting and safety discharge module is used for the discharge of liquid hydrogen during normal testing; and for emergency discharge and depressurization of liquid hydrogen in case of failure.

[0076] The external heat flow simulation module is used to regulate the external heat flow.

[0077] The measurement and control module is used to acquire temperature, pressure, and flow data; and to control the vacuum module, liquid hydrogen storage tank module, gas replacement and filling module, exhaust cooling test module, helium pressurization module, venting and safety discharge module, and external heat flow simulation module (i.e., control of the ambient temperature solenoid valves, cryogenic solenoid valves, electric regulating valves, and circulating pumps in the vacuum module, liquid hydrogen storage tank module, gas replacement and filling module, exhaust cooling test module, helium pressurization module, venting and safety discharge module, and external heat flow simulation module).

[0078] The specific structure and function of each module are explained in detail below.

[0079] Vacuum module

[0080] The vacuum module mainly includes: a vacuum tank 4, a vacuum tank support 5, a vacuum sealing flange 6, a lifting ring 7, a lifting tool 8, an explosion-proof vacuum unit 13, a vacuum pumping pipeline 14, a main vacuum silicon device 15, a backup vacuum silicon device 16, a vacuum tank explosion-proof plate 60, a manual valve A85, a nitrogen positive pressure explosion-proof box A86, a vacuum flange A93, a vacuum flange B94, a vacuum connector 95, and a vacuum flange C96. The vacuum tank 4 has an upper and lower structure connected by the vacuum sealing flange 6. The vacuum tank 4 is mounted on the vacuum tank support 5. The lifting ring 7 and the vacuum tank explosion-proof plate 60 are installed on the top of the vacuum tank 4; during assembly and disassembly, the upper part of the vacuum tank 4 is lifted by connecting the lifting ring 7 with the lifting tool 8. Vacuum flanges A93, B94, 95, and C96 are installed on the side walls of the vacuum tank 4. All inlet and outlet pipes and cables of vacuum tank 4 are connected to vacuum tank 4 via vacuum flange A93, vacuum flange B94, vacuum connector 95, and vacuum flange C96. The main vacuum silicon diaphragm 15 and the backup vacuum silicon diaphragm 16 are housed within a nitrogen positive pressure explosion-proof enclosure A86 and connected to the side wall of vacuum tank 4 via pipelines. A manual valve A85 is installed between the main vacuum silicon diaphragm 15, the backup vacuum silicon diaphragm 16, and the vacuum tank 4. The explosion-proof vacuum unit 13 is connected to the main vacuum silicon diaphragm 15 and the backup vacuum silicon diaphragm 16 via a vacuum pumping pipeline 14 and is used to measure the vacuum level of vacuum tank 4.

[0081] Liquid hydrogen storage tank module

[0082] The liquid hydrogen storage tank module mainly includes: a liquid hydrogen storage tank 1, a composite insulation layer 2, a low thermal conductivity support 3, a storage tank temperature sensor group 9, a storage tank pressure sensor 10, a cryogenic connector 11, a cryogenic flange A12, a ramp-type baffle 26, a cryogenic flange B104, and a cryogenic flange C105. The liquid hydrogen storage tank 1 is placed in a vacuum tank 4 via the low thermal conductivity support 3 for storing liquid hydrogen. The liquid hydrogen storage tank 1 is externally covered with a composite insulation layer 2; the composite insulation layer 2 consists of a variable density multilayer and a polyurethane foam layer, the variable density multilayer being composed of an aluminized polyester film reflective layer with a glass microsphere lattice structure. The cryogenic connector 11 is installed on the top of the liquid hydrogen storage tank 1; the storage tank temperature sensor group 9 is arranged inside the liquid hydrogen storage tank 1 and connected to the cryogenic connector 11 via wires to measure the temperature of the liquid hydrogen medium and determine the filling level. Cryogenic flanges A12 and B104 are installed on the top of the liquid hydrogen storage tank 1; cryogenic flange C105 is installed on the bottom of the liquid hydrogen storage tank 1. A ramp-type baffle 26 is installed inside the liquid hydrogen storage tank 1, located below the cryogenic flange A12, at a 45° angle to the axis of the liquid hydrogen storage tank 1. This baffle prevents liquid hydrogen from directly impacting the temperature measuring point and the liquid surface during filling and replenishment. A tank pressure sensor 10 is installed on top of the liquid hydrogen storage tank 1 to measure the pressure within the tank.

[0083] Gas replacement and filling module

[0084] The gas replacement and refueling module mainly includes: a nitrogen positive pressure explosion-proof box B17, a nitrogen replacement pipeline 18, a manual valve B19, a liquid hydrogen refueling pipeline 20, a manual valve C21, a cryogenic solenoid valve 22, a hydrogen replacement pipeline 23, a manual valve D24, a filter 25, a liquid safety valve 27, a high-altitude discharge pipe 32, a manual valve E33, a room-temperature solenoid valve A59, a refueling line pressure sensor 71, a refueling line temperature sensor 72, a room-temperature solenoid valve B89, and a gas composition analyzer 103. Specifically, one end of the nitrogen replacement pipeline 18 is connected to a nitrogen source, and the other end is sequentially connected to room-temperature solenoid valve A59, manual valve B19, and then, after converging with the hydrogen replacement pipeline 23, connects to the liquid hydrogen refueling pipeline 20. One end of the hydrogen replacement pipeline 23 is connected to a hydrogen source, and the other end is sequentially connected to manual valve D24, room-temperature solenoid valve B89, and then, after converging with the nitrogen replacement pipeline 18, connects to the liquid hydrogen refueling pipeline 20. One end of the liquid hydrogen refueling pipeline 20 is connected to a liquid hydrogen source, and the other end is sequentially connected to a filter 25, a manual valve C21, a liquid circuit safety valve 27, and a cryogenic solenoid valve 22. It then enters the vacuum tank 4 via vacuum flange B94, and subsequently enters the liquid hydrogen storage tank 1 via cryogenic flange A12. A refueling pressure sensor 71 and a refueling temperature sensor 72 are installed on the liquid hydrogen refueling pipeline 20, located between the filter 25 and the manual valve C21. A gas composition analyzer 103 is placed in a nitrogen positive pressure explosion-proof enclosure B17 and connected to a high-altitude vent pipe 32 via a pipeline. A manual valve E33 is installed on the connecting pipeline between the gas composition analyzer 103 and the high-altitude vent pipe 32. The portion of the liquid hydrogen refueling pipeline 20 outside the vacuum tank 4 is a vacuum-jacketed pipeline, while other sections are single-layer stainless steel pipes.

[0085] The working principle of the gas replacement and refueling module is as follows: During the refueling process of liquid hydrogen medium, nitrogen and hydrogen replacement are performed first before refueling. Liquid hydrogen medium is then refueled after the nitrogen and hydrogen replacement is completed.

[0086] Specifically:

[0087] During nitrogen purging: Nitrogen gas passes sequentially through ambient temperature solenoid valve A59, manual valve B19, filter 25, manual valve C21, and cryogenic solenoid valve 22 before entering liquid hydrogen storage tank 1; then, nitrogen purging is performed sequentially on the liquid hydrogen storage tank 1, safety discharge pipe 58, gas vent pipe 90, pre-cooling discharge pipe 92, exhaust cooling main pipe 91, exhaust manifold pipe A48, exhaust manifold pipe B97, and high-altitude discharge pipe 32, as well as the equipment on these pipes. The gas composition analyzer 103 is used to analyze the water content and oxygen content of the gas. Generally, nitrogen purging is considered complete when the dew point temperature drops below -60℃ and the oxygen content is less than 30ppm. The gas sampling and detection switch is activated by manual valve E33.

[0088] During hydrogen purging: Hydrogen gas sequentially passes through manual valve D24, ambient temperature solenoid valve B89, filter 25, manual valve C21, and cryogenic solenoid valve 22 before entering liquid hydrogen storage tank 1. Then, liquid hydrogen storage tank 1, related pipelines, and equipment on these pipelines are purged with hydrogen (the pipeline purging sequence is the same as the nitrogen purging sequence and will not be repeated). During hydrogen purging, the flow rate of hydrogen is controlled to ensure that the flow rate of hydrogen filling liquid hydrogen storage tank 1 does not exceed 252 m / s. This prevents high oxygen content or localized high oxygen content in liquid hydrogen storage tank 1 from causing static electricity generated by high-speed gas flow and friction with the pipelines, which could lead to fire or explosion.

[0089] After nitrogen and hydrogen purging are completed, liquid hydrogen is added: liquid hydrogen enters liquid hydrogen storage tank 1 sequentially through filter 25, manual valve C21, and cryogenic solenoid valve 22; after addition, manual valve C21 and cryogenic solenoid valve 22 are closed; the residual liquid hydrogen between the closed manual valve C21 and cryogenic solenoid valve 22 evaporates upon heating, and is discharged through liquid circuit safety valve 27 after reaching a certain pressure. After the liquid hydrogen is added, an exhaust cooling test is performed.

[0090] Exhaust Cooling Test Module

[0091] The exhaust cooling test module mainly includes: exhaust main pipe 28, ambient temperature vaporizer 29, ambient temperature solenoid valve C34, ambient temperature solenoid valve D35, ambient temperature solenoid valve E36, ambient temperature solenoid valve F37, throttle valve A38, throttle valve B39, throttle valve C40, throttle valve D41, electric regulating valve 42, gas mass flow meter A43, gas mass flow meter B44, exhaust manifold A48, manual valve F57, gas vacuum pipeline 67, exhaust line front pressure sensor 73, exhaust line front temperature sensor 74, exhaust line rear pressure sensor 75, exhaust line rear temperature sensor 76, exhaust cooling main pipe 91, and exhaust manifold B97. Among them, the section of the exhaust main pipeline 28 between the vacuum tank 4 and the ambient temperature vaporizer 29 is a vacuum pipeline; one end of the exhaust main pipeline 28 enters the liquid hydrogen storage tank 1 through the cryogenic flange B104, and the other end exits the vacuum tank 4 through the vacuum flange C96, and is connected in sequence to the gas vacuum pipeline 67, the ambient temperature vaporizer 29, the exhaust cooling main pipeline 91, the exhaust line temperature sensor 74, the exhaust line pressure sensor 73, and the manual valve F57. The exhaust cooling main pipe 91 is divided into four branches: the first branch is connected in sequence to the ambient temperature solenoid valve C34 and the throttle valve D41; the second branch is connected in sequence to the ambient temperature solenoid valve D35 and the throttle valve C40; the third branch is connected in sequence to the ambient temperature solenoid valve E36 and the throttle valve B39; the fourth branch is connected in sequence to the ambient temperature solenoid valve F37, the throttle valve A38 and the electric regulating valve 42; the first and second branches are connected in parallel and then connected to one end of the exhaust manifold A48, the other end of which is connected to one end of the gas mass flow meter B44; the third and fourth branches are connected in parallel and then connected to one end of the exhaust manifold B97, the other end of which is connected to one end of the gas mass flow meter A43; the other ends of the gas mass flow meter B44 and the other ends of the gas mass flow meter A43 are connected in sequence to the exhaust pressure sensor 75, the exhaust temperature sensor 76 and the high-altitude discharge pipe 32. Throttling valves A38, B39, C40, and D41 are throttling valves with different orifice diameters. The ambient air vaporizer 29 has a multi-channel structure and is used to heat cryogenic gases to room temperature. Gas mass flow meters A43 and B44 are used to measure the flow rate of gas passing through different exhaust manifolds, enabling the measurement of different gas flow rates. The appropriate gas mass flow meter A43 can be selected based on the exhaust flow rate of the first and second branches, and the appropriate gas mass flow meter B44 can be selected based on the exhaust flow rate of the third and fourth branches. The exhaust path pressure sensor 73 and exhaust path temperature sensor 74 are used to measure the gas pressure and temperature after passing through the ambient air vaporizer 29; the exhaust path pressure sensor 75 and exhaust path temperature sensor 76 are used to measure the gas pressure and temperature after passing through gas mass flow meter A43 or gas mass flow meter B44.

[0092] The working principle of the exhaust cooling test module is as follows: During the exhaust cooling test, the manual valve F57 is kept open. According to the pressure or temperature change in the liquid hydrogen storage tank 1, one of the following is opened each time: the ambient temperature solenoid valve C34 and throttle valve D41 in the first branch, the ambient temperature solenoid valve D35 and throttle valve C40 in the second branch, the ambient temperature solenoid valve E36 and throttle valve B39 in the third branch, and the ambient temperature solenoid valve F37, throttle valve A38 and electric regulating valve 42 in the fourth branch, to verify the effect of different exhaust flow rates on the rate of temperature reduction of liquid hydrogen medium.

[0093] Helium booster module

[0094] The helium booster module mainly includes: a room-temperature solenoid valve G49, a manual valve G50, a flow controller 51, a booster circuit pressure sensor 69, a booster circuit temperature sensor 70, and a helium pipeline 98. One end of the helium pipeline 98 is connected to a helium source, and the other end is sequentially connected to the room-temperature solenoid valve G49, the booster circuit pressure sensor 69, the booster circuit temperature sensor 70, the manual valve G50, and the flow controller 51 before being connected to the liquid hydrogen refueling pipeline 20.

[0095] The pressurization process of the helium pressurization module for the liquid hydrogen storage tank is as follows: the helium pressurization gas enters the liquid hydrogen filling pipeline 20 from the helium source in sequence through the ambient temperature solenoid valve G49, the pressurization circuit pressure sensor 69, the pressurization circuit temperature sensor 70, the manual valve G50, and the flow controller 51; then it enters the vacuum tank 4 through the vacuum flange B94; and then enters the liquid hydrogen storage tank 1 through the cryogenic flange A12, thus finally pressurizing the liquid hydrogen storage tank 1.

[0096] Leakage and safety discharge module

[0097] The venting and safety discharge module mainly includes: manual valve H30, ambient temperature solenoid valve H31, tank venting pipeline 45, ambient temperature solenoid valve I46, manual valve I47, main gas safety valve 52, backup gas safety valve 53, main gas explosion-proof plate 54, backup gas explosion-proof plate 55, three-phase plug valve 56, safety discharge pipe 58, nitrogen purging pipeline 61, ambient temperature solenoid valve J62, manual valve J63, liquid vacuum pipeline 68, manual valve K87, gas venting pipe 90, and pre-cooling discharge pipe 92. Specifically, one end of the tank venting pipeline 45 is connected to the liquid hydrogen storage tank 1 via a cryogenic flange C105; the other end exits the vacuum tank 4 via a vacuum flange C96, and is sequentially connected to the liquid vacuum pipeline 68, ambient temperature vaporizer 29, gas venting pipe 90, and high-altitude discharge pipe 32. The gas venting pipe 90 is sequentially equipped with a manual valve I47 and an ambient temperature solenoid valve I46. One end of the safety discharge pipe 58 is connected to the exhaust cooling main pipe 91, and the other end is connected to the high-altitude discharge pipe 32. The safety discharge pipe 58 is sequentially equipped with a manual valve K87, a three-phase plug valve 56, a main gas line safety valve 52, and a backup gas line safety valve 53. The main gas line safety valve 52 and the backup gas line safety valve 53 are connected in parallel. The main gas line explosion-proof plate 54 is connected in parallel with the main gas line safety valve 52, and the backup gas line explosion-proof plate 55 is connected in parallel with the backup gas line safety valve 53. One end of the nitrogen purging pipe 61 is connected to a nitrogen source, and the other end is sequentially connected to a room-temperature solenoid valve J62 and a manual valve J63, entering the vacuum tank 4 via a vacuum flange B94. One end of the pre-cooling discharge pipe 92 is connected to the exhaust cooling main pipe 91, and the other end is connected to the high-altitude discharge pipe 32. The pre-cooling discharge pipe 92 is sequentially equipped with a manual valve H30 and a room-temperature solenoid valve H31. The venting and safety discharge module shares an ambient temperature vaporizer with the exhaust cooling test module. The main gas safety valve 52 and the backup gas safety valve 53 are switched via a three-phase plug valve 56. The internal drain pipe 45 is designed as an "n"-shaped bend inside the vacuum tank 4, with the height of the bend higher than the liquid level being filled.

[0098] The working principle of the leakage and safe discharge module is as follows:

[0099] During normal testing, manual valves H30, I47, J63, and K87 are normally open. Before the liquid level meets the requirements, the vaporized hydrogen is discharged through the pre-cooling discharge pipe 92.

[0100] When the test is completed or when it is necessary to release the residual liquid hydrogen in the liquid hydrogen storage tank 1, open the ambient temperature solenoid valve I46. The liquid hydrogen flows out of the liquid hydrogen storage tank 1, is heated and vaporized into ambient temperature hydrogen by the ambient temperature vaporizer 29, and then enters the high-altitude discharge pipe 32 through the gas discharge pipe 90 and is discharged into the atmosphere.

[0101] When the pressure inside the liquid hydrogen storage tank 1 rises sharply due to significant heat leakage, the cryogenic hydrogen gas flows sequentially through the exhaust main pipe 28, the gas vacuum pipe 67, the ambient temperature vaporizer 29, the safety discharge pipe 58, the manual valve K87, the main gas circuit safety valve 52 / backup gas circuit safety valve 53, and finally is discharged to the atmosphere through the high-altitude discharge pipe 32. If the pressure continues to rise and exceeds the discharge capacity of the main gas circuit safety valve 52 / backup gas circuit safety valve 53, the main gas circuit explosion-proof disc 54 / backup gas circuit explosion-proof disc 55 will activate, allowing the gas to escape more quickly.

[0102] When the liquid hydrogen storage tank 1 leaks, causing the pressure inside the vacuum tank 4 to rise, the ambient temperature solenoid valve J62 is opened to introduce nitrogen into the vacuum tank 4 to dilute the hydrogen. Then the gas is discharged from the explosion-proof plate 60 of the vacuum tank until all the liquid hydrogen is discharged.

[0103] External heat flow simulation module

[0104] The external heat flow simulation module mainly includes: a constant temperature water tank 64, a circulating pump 65, a radiation screen 66, a nitrogen positive pressure explosion-proof box C81, a manual valve L82, a manual valve M83, a heat sink circulation inlet pipe 84, a radiation screen coil 88, a heat sink circulation outlet pipe 99, a heat sink inlet temperature sensor 100, and a heat sink outlet temperature sensor 101. The radiation screen 66 is installed on the inner wall of the upper structure of the vacuum tank 4; the radiation screen coil 88 is installed on the radiation screen 66. It is located between the liquid hydrogen storage tank 1 and the vacuum tank 4. The constant temperature water tank 64 is connected to the circulating pump 65 and is placed inside the nitrogen positive pressure explosion-proof box C81. One end of the heat sink circulation inlet pipe 84 is connected to the circulation pump 65, and the other end enters the vacuum tank 4 through the vacuum flange A93 and connects to the radiation screen coil 88 on the radiation screen 66; then it exits the vacuum tank 4 through the vacuum flange A93 and connects to one end of the heat sink circulation outlet pipe 99; the other end of the heat sink circulation outlet pipe 99 is connected to the constant temperature water tank 64, forming a circulation loop. A manual valve L82 and a heat sink inlet temperature sensor 100 are sequentially installed on the heat sink circulation inlet pipe 84, and a manual valve M83 and a heat sink outlet temperature sensor 101 are sequentially installed on the heat sink circulation outlet pipe 99.

[0105] The external heat flow simulation module regulates the temperature of the radiation screen 66 by adjusting the water temperature of the constant temperature water tank 64, thereby regulating the external heat flow. Specifically: first, adjust the water temperature of the constant temperature water tank 64, and open the manual valves L82 and M83; then, start the circulation pump 65, and the external heat flow simulation module will begin to run.

[0106] Measurement and Control Module

[0107] The measurement and control module mainly includes: a data acquisition unit 77, a PLC controller 78, an Ethernet switch 79, a measurement and control computer 80, and a regulated power supply 102. The measurement and control computer 80 is located in the space at the far end of the vacuum tank 4; the data acquisition unit 77, the PLC controller 78, and the Ethernet switch 79 are located inside a nitrogen positive pressure explosion-proof box C81; the measurement and control computer 80 is connected to the data acquisition unit 77 and the PLC controller 78 via the Ethernet switch 79; the regulated power supply 102 is connected to the data acquisition unit 77, the PLC controller 78, the Ethernet switch 79, and the measurement and control computer 80, providing power to these components.

[0108] The main functions of the measurement and control module include: acquiring temperature, pressure, and flow data; controlling the switching of all ambient temperature solenoid valves, cryogenic solenoid valves, and circulating pumps within the system; and controlling the regulation of electric regulating valves. Specifically: the data acquisition unit 77 is used to acquire all temperature, pressure, and flow data within the system. The PLC controller 78 is used to control the switching of all ambient temperature solenoid valves, cryogenic solenoid valves, and circulating pumps within the system, as well as controlling the regulation of electric regulating valves. The temperature, pressure, and flow data acquired by the data acquisition unit 77, along with the control commands used to control the switching of all ambient temperature solenoid valves, cryogenic solenoid valves, and circulating pumps, and to control the regulation of electric regulating valves, interact with the remote measurement and control computer 80 via the Ethernet switch 79 to achieve the entire data acquisition, storage, and control of the actuators (ambient temperature solenoid valves, cryogenic solenoid valves, circulating pumps, and electric regulating valves).

[0109] In this embodiment, all the ambient temperature solenoid valves, cryogenic solenoid valves, electric regulating valves, temperature sensors, pressure sensors, and gas mass flow meters in the liquid hydrogen medium active exhaust cooling test system have explosion-proof functions.

[0110] Based on the above embodiments, the present invention also discloses a method for active exhaust cooling test of liquid hydrogen medium, comprising:

[0111] S1. Construct a liquid hydrogen medium active venting and cooling test system, including but not limited to: hoisting and fixing the liquid hydrogen storage tank module into the vacuum tank, and connecting the external pipeline interfaces and test control cables. The liquid hydrogen medium active venting and cooling test system includes: a vacuum module, a liquid hydrogen storage tank module, a gas replacement and filling module, a venting and cooling test module, a helium pressurization module, and a leakage and safety discharge module.

[0112] S2, perform pre-test checks on the active exhaust cooling test system for liquid hydrogen, including but not limited to: pipeline sealing test check; if the sealing meets the requirements, turn on the measurement and control module to measure, collect and save the initial data.

[0113] S3, the vacuum module is activated, performing vacuuming, including but not limited to: opening manual valve A, activating the explosion-proof vacuum unit, and starting vacuuming the vacuum tank to achieve the required vacuum level (generally less than 10). -3 Pa).

[0114] S4, through the gas replacement and refueling module, sequentially performs nitrogen replacement, hydrogen replacement, and liquid hydrogen refueling, including but not limited to:

[0115] Open ambient temperature solenoid valve A59, manual valve B19, manual valve C21, cryogenic solenoid valve 22, manual valve F57, and ambient temperature solenoid valve C34 to perform nitrogen purging: Nitrogen gas sequentially passes through ambient temperature solenoid valve A59, manual valve B19, filter 25, manual valve C21, and cryogenic solenoid valve 22 into liquid hydrogen storage tank 1. Then, nitrogen purging is performed sequentially on the liquid hydrogen storage tank 1, safety discharge pipe 58, gas vent pipe 90, pre-cooling discharge pipe 92, exhaust cooling main pipe 91, exhaust manifold A48, exhaust manifold B97, and high-altitude discharge pipe 32, as well as the equipment on the pipes. Open manual valve E33 and analyze the water content and oxygen content of the gas using gas composition analyzer 103. Nitrogen purging is considered complete when the dew point temperature drops below -60℃ and the oxygen content is less than 30ppm.

[0116] Close ambient temperature solenoid valve C34, and sequentially open ambient temperature solenoid valves D35, E36, and F37 to perform hydrogen purging: Hydrogen gas passes sequentially through manual valve D24, ambient temperature solenoid valve B89, filter 25, manual valve C21, and cryogenic solenoid valve 22 before entering liquid hydrogen storage tank 1. Then, hydrogen purging is performed on liquid hydrogen storage tank 1, related pipelines, and equipment on these pipelines. During hydrogen purging, the flow rate of hydrogen filling liquid hydrogen storage tank 1 is controlled to not exceed 252 m / s. This prevents fires and explosions caused by static electricity generated from high oxygen content or localized areas in liquid hydrogen storage tank 1, which could lead to high-speed gas flow and friction with the pipelines. The pipeline purging sequence during hydrogen purging is the same as that during nitrogen purging. After hydrogen replacement is completed, close manual valves D24 and E33; before liquid hydrogen refueling, keep manual valves A85, B19, C21, F57, G50, H30, I47, J63, K87, L82, and M83 in the open state, and keep other valves in the closed state.

[0117] Adding liquid hydrogen: Open cryogenic solenoid valve 22 and ambient temperature solenoid valve H31; liquid hydrogen enters liquid hydrogen storage tank 1 after passing through filter 25, manual valve C21, and cryogenic solenoid valve 22 in sequence; determine the liquid hydrogen level based on the temperature change of storage tank temperature sensor group 9 located at different heights of liquid hydrogen storage tank 1; after the liquid level is reached, the addition is completed, and close manual valve C21, cryogenic solenoid valve 22, and ambient temperature solenoid valve H31; the liquid hydrogen remaining between manual valve C21 and cryogenic solenoid valve 22 evaporates upon heating, and is discharged through liquid circuit safety valve 27 after reaching a certain pressure.

[0118] S5, through the external heat flow simulation module and the helium pressurization module, completes the regulation of external heat flow and the pressurization of the liquid hydrogen storage tank, including but not limited to:

[0119] The external heat flow simulation module is activated, and the water temperature in the constant temperature water tank 64 is adjusted to the required value. The circulation pump 65 is activated to ensure that the liquid temperature entering the radiation screen 66 meets the requirements of the external heat flow simulation. Due to the external heat flow, the liquid hydrogen in the liquid hydrogen storage tank 1 evaporates, causing the pressure inside the liquid hydrogen storage tank 1 to rise. When the pressure inside the liquid hydrogen storage tank 1 rises to P... up It completes self-pressurization in time.

[0120] S6, through the exhaust cooling test module, adjusts different exhaust flow rates to conduct exhaust cooling tests, verifying the effect of different exhaust flow rates on the rate of temperature decrease of liquid hydrogen medium, including but not limited to:

[0121] Open the ambient temperature solenoid valve C34 to allow gaseous hydrogen in liquid hydrogen storage tank 1 to pass sequentially through ambient temperature vaporizer 29, manual valve F57, ambient temperature solenoid valve C34, throttle valve D41, and gas mass flow meter B44 before being discharged through high-altitude exhaust pipe 32. During the discharge process, measure the exhaust flow rate, exhaust duration, temperature, and pressure of the discharged gas. When the pressure in liquid hydrogen storage tank 1 drops to P, the discharge is completed. down When the time is up, close the ambient temperature solenoid valve C34, and one exhaust test is completed.

[0122] Liquid hydrogen storage tank 1 is repressurized due to external heat flow; when the pressure inside liquid hydrogen storage tank 1 rises to P... up Then, open the ambient temperature solenoid valve C34 again; repeat this process three times to complete the measurement of exhaust gas passing through the throttle valve D41, and then close the ambient temperature solenoid valve C34.

[0123] When liquid hydrogen storage tank 1 needs to be replenished, open cryogenic solenoid valve 22, ambient temperature solenoid valve H31 and manual valve C21 to replenish liquid hydrogen storage tank 1; after replenishing to the required liquid level, close cryogenic solenoid valve 22, ambient temperature solenoid valve H31 and manual valve C21 to complete the replenishment.

[0124] The same pressure drop range (P) was sequentially applied to the pipelines containing throttle valves C40, B39, and A38. up ~Pdown Exhaust cooling tests were conducted on different throttling orifice diameters. Among these, P can be adjusted. up and P down Experiments were conducted on different pressure drop ranges and different throttling orifice diameters.

[0125] After the exhaust cooling test is completed, close the ambient temperature solenoid valves C34, D35, E36, and F37.

[0126] S7, after the exhaust cooling test is completed, completes the discharge of liquid hydrogen through the venting and safety discharge module, including but not limited to:

[0127] After the exhaust cooling test is completed, open the ambient temperature solenoid valve I46 to connect the gas vent pipe 90, open the ambient temperature solenoid valve G49 to input helium pressurizing gas into the liquid hydrogen storage tank 1 to increase the pressure inside the liquid hydrogen storage tank 1; measure the pressurizing gas flow rate through the flow controller 51 to allow the liquid hydrogen medium to vent; after the liquid hydrogen medium has vented, close the ambient temperature solenoid valve G49 and open the ambient temperature solenoid valve A59 to fully purge and reheat the liquid hydrogen storage tank 1 with nitrogen; after the nitrogen purge and reheat are completed, close the ambient temperature solenoid valve A59.

[0128] S8, shut down the vacuum module, the test is complete, including but not limited to: shutting down the explosion-proof vacuum unit 13, stopping the vacuuming, and restoring the vacuum tank 4 to normal pressure, the test is complete.

[0129] In this embodiment, if a large-scale leak occurs in the liquid hydrogen storage tank 1 during or after the liquid hydrogen refueling process, causing a sudden increase in pressure inside the vacuum tank 4, the vacuum tank explosion-proof plate 60 at the top of the vacuum tank 4 will burst under pressure, initiating emergency venting and opening the ambient temperature solenoid valve J62 to inject nitrogen into the vacuum tank 4 for nitrogen replacement until all liquid hydrogen is discharged.

[0130] In this embodiment, if the evaporation rate of liquid hydrogen storage tank 1 suddenly increases during or after liquid hydrogen refueling, causing the pressure inside liquid hydrogen storage tank 1 to exceed the requirement, the main gas circuit safety valve 52 / backup gas circuit safety valve 53 will open to release pressure. If the pressure continues to rise, the main gas circuit explosion-proof plate 54 / backup gas circuit explosion-proof plate 55 will open, and the ambient temperature solenoid valve G49 will open to inject helium into liquid hydrogen storage tank 1 to complete the pressure release.

[0131] The above method embodiments are described simply because they correspond to the system embodiments. For relevant details, please refer to the description in the system embodiments section.

[0132] In summary, this invention discloses an active venting and cooling test system and method for liquid hydrogen media. It features liquid hydrogen storage, vacuum acquisition and maintenance, and can verify liquid hydrogen temperature control strategies under different liquid hydrogen refueling levels, pressure bands, and temperature bands. This system can be used to verify venting and cooling during the on-orbit application of liquid hydrogen propellants, supporting the development of long-term on-orbit application technology for cryogenic propellants.

[0133] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

[0134] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A liquid hydrogen medium active exhaust cooling test system, characterized in that, include: Vacuum module, used to obtain and maintain the vacuum environment of the test system; Liquid hydrogen storage tank module, used for liquid level measurement during liquid hydrogen refilling and thermal stratification measurement during storage; The gas replacement and filling module is used for nitrogen and hydrogen replacement before liquid hydrogen medium filling, and for liquid hydrogen medium filling after the replacement is completed. The exhaust cooling test module is used to adjust different exhaust flow rates during exhaust cooling tests to verify the effect of different exhaust flow rates on the rate of temperature reduction of liquid hydrogen medium. The helium pressurization module is used to pressurize the liquid hydrogen storage tank. The venting and safety discharge module is used for the discharge of liquid hydrogen during normal testing. In addition, emergency discharge and depressurization of liquid hydrogen medium in the event of a failure; The external heat flow simulation module is used to regulate the external heat flow. The measurement and control module is used to acquire temperature, pressure, and flow data; and to control the vacuum module, liquid hydrogen storage tank module, gas replacement and filling module, exhaust cooling test module, helium pressurization module, venting and safety discharge module, and external heat flow simulation module.

2. The liquid hydrogen medium active exhaust cooling test system according to claim 1, characterized in that, The vacuum module includes: a vacuum tank (4), a vacuum tank support (5), a vacuum sealing flange (6), a lifting ring (7), a lifting tool (8), an explosion-proof vacuum unit (13), a vacuum pumping pipeline (14), a main vacuum silicon device (15), a backup vacuum silicon device (16), a vacuum tank explosion-proof plate (60), a manual valve A (85), a nitrogen positive pressure explosion-proof box A (86), a vacuum flange A (93), a vacuum flange B (94), a vacuum connector (95), and a vacuum flange C (96); The vacuum tank (4) has an upper and lower structure, and the upper and lower structures are connected by a vacuum sealing flange (6); The vacuum container (4) is mounted on the vacuum container support (5); The lifting ring (7) and the vacuum tank explosion-proof plate (60) are installed on the top of the vacuum tank (4); during disassembly and assembly, the lifting ring (7) is connected by the lifting tool (8) to lift the upper part of the vacuum tank (4); Vacuum flange A (93), vacuum flange B (94), vacuum connector (95) and vacuum flange C (96) are respectively installed on the side wall of vacuum tank (4); The main vacuum silicon (15) and the backup vacuum silicon (16) are placed in a nitrogen positive pressure explosion-proof box A (86) and connected to the side wall of the vacuum tank (4) through pipelines; A manual valve A (85) is provided between the main vacuum silicon (15) and the backup vacuum silicon (16) and the vacuum tank (4); The explosion-proof vacuum unit (13) is connected to the main vacuum silicon (15) and the backup vacuum silicon (16) through the vacuum pumping pipeline (14) and is used to measure the vacuum degree of the vacuum tank (4).

3. The liquid hydrogen medium active exhaust cooling test system according to claim 2, characterized in that, The liquid hydrogen storage tank module includes: a liquid hydrogen storage tank (1), a composite insulation layer (2), a low thermal conductivity support (3), a storage tank temperature sensor group (9), a storage tank pressure sensor (10), a cryogenic connector (11), a cryogenic flange A (12), a ramp baffle (26), a cryogenic flange B (104), and a cryogenic flange C (105). Liquid hydrogen storage tank (1) is used for storing liquid hydrogen medium; wherein, the liquid hydrogen storage tank (1) is placed in a vacuum tank (4) by a low thermal conductivity support (3); the liquid hydrogen storage tank (1) is covered with a composite insulation layer (2) on the outside; The cryogenic connector (11) is installed on the top of the liquid hydrogen storage tank (1); the storage tank temperature sensor group (9) is arranged inside the liquid hydrogen storage tank (1) and connected to the cryogenic connector (11) through wires to realize the measurement of the liquid hydrogen medium temperature and the determination of the filling level; Cryogenic flange A (12) and cryogenic flange B (104) are installed on top of liquid hydrogen storage tank (1); A ramp-type baffle (26) is installed inside the liquid hydrogen storage tank (1), located below the cryogenic flange A (12), at a 45° angle to the axis of the liquid hydrogen storage tank (1), to prevent the liquid from rushing directly to the liquid surface during filling; The cryogenic flange C(105) is installed at the bottom of the liquid hydrogen storage tank (1); The tank pressure sensor (10) is installed on top of the liquid hydrogen tank (1) to measure the pressure of the liquid hydrogen tank (1).

4. The liquid hydrogen medium active exhaust cooling test system according to claim 3, characterized in that, The gas replacement and filling module includes: nitrogen positive pressure explosion-proof box B (17), nitrogen replacement pipeline (18), manual valve B (19), liquid hydrogen filling pipeline (20), manual valve C (21), cryogenic solenoid valve (22), hydrogen replacement pipeline (23), manual valve D (24), filter (25), liquid safety valve (27), high-altitude discharge pipe (32), manual valve E (33), ambient temperature solenoid valve A (59), filling line pressure sensor (71), filling line temperature sensor (72), ambient temperature solenoid valve B (89), and gas composition analyzer (103); One end of the nitrogen replacement pipeline (18) is connected to the nitrogen source, and the other end is connected in sequence to the ambient temperature solenoid valve A (59), the manual valve B (19), and then connected to the liquid hydrogen filling pipeline (20) after being combined with the hydrogen replacement pipeline (23). One end of the hydrogen replacement pipeline (23) is connected to the hydrogen source, and the other end is connected in sequence to the manual valve D (24), the ambient temperature solenoid valve B (89), and then connected to the liquid hydrogen filling pipeline (20) after being combined with the nitrogen replacement pipeline (18). One end of the liquid hydrogen filling pipeline (20) is connected to the liquid hydrogen source, and the other end is connected in sequence to the filter (25), manual valve C (21), liquid circuit safety valve (27), and cryogenic solenoid valve (22). Then it enters the vacuum tank (4) through the vacuum flange B (94) and then enters the liquid hydrogen storage tank (1) through the cryogenic flange A (12). The filling line pressure sensor (71) and the filling line temperature sensor (72) are installed on the liquid hydrogen filling line (20), located between the filter (25) and the manual valve C (21); The gas composition analyzer (103) is placed in a nitrogen positive pressure explosion-proof box B (17) and connected to the high-altitude exhaust pipe (32) through a pipeline; a manual valve E (33) is installed on the connecting pipeline between the gas composition analyzer (103) and the high-altitude exhaust pipe (32).

5. The liquid hydrogen medium active exhaust cooling test system according to claim 4, characterized in that, The exhaust cooling test module includes: exhaust main pipeline (28), ambient temperature vaporizer (29), ambient temperature solenoid valve C (34), ambient temperature solenoid valve D (35), ambient temperature solenoid valve E (36), ambient temperature solenoid valve F (37), throttle valve A (38), throttle valve B (39), throttle valve C (40), throttle valve D (41), electric regulating valve (42), gas mass flow meter A (43), gas mass flow meter B (44), exhaust manifold A (48), manual valve F (57), gas vacuum pipeline (67), exhaust line front pressure sensor (73), exhaust line front temperature sensor (74), exhaust line rear pressure sensor (75), exhaust line rear temperature sensor (76), exhaust cooling main pipeline (91) and exhaust manifold B (97); One end of the exhaust main pipeline (28) enters the liquid hydrogen storage tank (1) through the cryogenic flange B (104), and the other end exits the vacuum tank (4) through the vacuum flange C (96), and is connected in sequence to the gas vacuum pipeline (67), the ambient temperature vaporizer (29), the exhaust cooling main pipeline (91), the exhaust line temperature sensor (74), the exhaust line pressure sensor (73), and the manual valve F (57); The exhaust cooling main pipe (91) is divided into four branches: the first branch is connected in sequence to the ambient temperature solenoid valve C (34) and the throttle valve D (41); the second branch is connected in sequence to the ambient temperature solenoid valve D (35) and the throttle valve C (40); the third branch is connected in sequence to the ambient temperature solenoid valve E (36) and the throttle valve B (39); the fourth branch is connected in sequence to the ambient temperature solenoid valve F (37), the throttle valve A (38) and the electric regulating valve (42); the first and second branches are connected in parallel and then connected to one end of the exhaust manifold A (48). The other end of the exhaust manifold A (48) is connected to one end of the gas mass flow meter B (44); the third and fourth branches are connected in parallel and then connected to one end of the exhaust manifold B (97), and the other end of the exhaust manifold B (97) is connected to one end of the gas mass flow meter A (43); the other end of the gas mass flow meter B (44) and the other end of the gas mass flow meter A (43) are connected in sequence to the exhaust pressure sensor (75), the exhaust temperature sensor (76), and the high-altitude exhaust pipe (32).

6. The liquid hydrogen medium active exhaust cooling test system according to claim 5, characterized in that, The helium booster module includes: a normal temperature solenoid valve G (49), a manual valve G (50), a flow controller (51), a booster circuit pressure sensor (69), a booster circuit temperature sensor (70), and a helium pipeline (98). One end of the helium pipeline (98) is connected to the helium source, and the other end is connected in sequence to the ambient temperature solenoid valve G (49), the pressure sensor of the booster circuit (69), the temperature sensor of the booster circuit (70), the manual valve G (50), and the flow controller (51), and then connected to the liquid hydrogen filling pipeline (20).

7. The liquid hydrogen medium active exhaust cooling test system according to claim 6, characterized in that, The leakage and safety discharge module includes: manual valve H (30), ambient temperature solenoid valve H (31), tank leakage pipeline (45), ambient temperature solenoid valve I (46), manual valve I (47), main gas safety valve (52), backup gas safety valve (53), main gas explosion-proof plate (54), backup gas explosion-proof plate (55), three-phase plug valve (56), safety discharge pipe (58), nitrogen purging pipeline (61), ambient temperature solenoid valve J (62), manual valve J (63), liquid vacuum pipeline (68), manual valve K (87), gas leakage pipe (90) and pre-cooling discharge pipe (92); One end of the in-tank discharge pipeline (45) is connected to the liquid hydrogen storage tank (1) via the cryogenic flange C (105); the other end is connected to the vacuum tank (4) via the vacuum flange C (96), and then to the liquid vacuum pipeline (68), the ambient temperature vaporizer (29), the gas discharge pipe (90), and the high-altitude discharge pipe (32) in sequence; the gas discharge pipe (90) is equipped with a manual valve I (47) and a normal temperature solenoid valve I (46) in sequence; One end of the safety discharge pipe (58) is connected to the exhaust cooling main pipe (91), and the other end is connected to the high-altitude discharge pipe (32); a manual valve K (87), a three-phase plug valve (56), a main gas circuit safety valve (52), and a backup gas circuit safety valve (53) are sequentially installed on the safety discharge pipe (58); the main gas circuit safety valve (52) and the backup gas circuit safety valve (53) are connected in parallel, the main gas circuit explosion-proof plate (54) is connected in parallel with the main gas circuit safety valve (52), and the backup gas circuit explosion-proof plate (55) is connected in parallel with the backup gas circuit safety valve (53); One end of the nitrogen purging pipeline (61) is connected to a nitrogen source, and the other end is connected in sequence to a normal temperature solenoid valve J (62) and a manual valve J (63), and enters the vacuum tank (4) through the vacuum flange B (94); One end of the precooling discharge pipe (92) is connected to the exhaust cooling main pipe (91), and the other end is connected to the high-altitude discharge pipe (32); a manual valve H (30) and a normal temperature solenoid valve H (31) are installed on the precooling discharge pipe (92) in sequence.

8. The liquid hydrogen medium active exhaust cooling test system according to claim 7, characterized in that, The external heat flow simulation module includes: a constant temperature water tank (64), a circulating pump (65), a radiation screen (66), a nitrogen positive pressure explosion-proof box C (81), a manual valve L (82), a manual valve M (83), a heat sink circulation inlet pipe (84), a radiation screen coil (88), a heat sink circulation outlet pipe (99), a heat sink inlet temperature sensor (100), and a heat sink outlet temperature sensor (101); The radiation screen (66) is installed on the inner wall of the upper part of the vacuum tank (4); the radiation screen coil (88) is installed on the radiation screen (66); It is positioned between the liquid hydrogen storage tank (1) and the vacuum tank (4); The constant temperature water tank (64) is connected to the circulating pump (65) and placed inside the nitrogen positive pressure explosion-proof box C (81); One end of the heat sink circulation inlet pipe (84) is connected to the circulation pump (65), and the other end enters the vacuum tank (4) through the vacuum flange A (93) and is connected to the radiation screen coil (88) on the radiation screen (66); then it exits the vacuum tank (4) through the vacuum flange A (93) and is connected to one end of the heat sink circulation outlet pipe (99); the other end of the heat sink circulation outlet pipe (99) is connected to the constant temperature water tank (64) to form a circulation loop; A manual valve L (82) and a heat sink inlet temperature sensor (100) are sequentially installed on the heat sink circulation inlet pipe (84), and a manual valve M (83) and a heat sink outlet temperature sensor (101) are sequentially installed on the heat sink circulation outlet pipe (99).

9. The liquid hydrogen medium active exhaust cooling test system according to claim 8, characterized in that, The measurement and control module includes: a data acquisition instrument (77), a PLC controller (78), an Ethernet switch (79), a measurement and control computer (80), and a regulated power supply (102); The measurement and control computer (80) is placed in the space at the far end of the vacuum tank (4); The data acquisition unit (77), PLC controller (78) and Ethernet switch (79) are placed in a nitrogen positive pressure explosion-proof box C (81); The measurement and control computer (80) is connected to the data acquisition instrument (77) and the PLC controller (78) respectively via an Ethernet switch (79); The regulated power supply (102) is connected to the data acquisition instrument (77), PLC controller (78), Ethernet switch (79) and measurement and control computer (80) respectively, and provides power to the data acquisition instrument (77), PLC controller (78), Ethernet switch (79) and measurement and control computer (80).

10. A test method for active exhaust cooling of liquid hydrogen medium, characterized in that, include: An active venting and cooling test system for liquid hydrogen was constructed. The active venting and cooling test system for liquid hydrogen includes: a vacuum module, a liquid hydrogen storage tank module, a gas replacement and filling module, a venting and cooling test module, a helium pressurization module, and a leakage and safe discharge module. Pre-test inspection of the active exhaust cooling test system for liquid hydrogen medium; The vacuum module is in operation, performing vacuuming. Nitrogen replacement, hydrogen replacement, and liquid hydrogen medium injection are performed sequentially through the gas replacement and injection modules. The external heat flow is regulated and the liquid hydrogen storage tank is pressurized by the external heat flow simulation module and the helium pressurization module. The exhaust cooling test module allows for the adjustment of different exhaust flow rates to conduct exhaust cooling tests and verify the effect of different exhaust flow rates on the rate of temperature reduction of liquid hydrogen medium. After the exhaust cooling test is completed, the liquid hydrogen medium is discharged through the venting and safe discharge module; The vacuum module was shut down, and the experiment was completed.

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