Hydrogen pump and / or oxygen pump high-temperature inlet condition control and test method
By controlling the tank pressure and allowing the pressure to remain constant and reheat, the challenge of verifying the operation of the hydrogen-oxygen engine under high-temperature inlet conditions was solved. This enabled precise control of the liquid hydrogen and liquid oxygen temperatures, improving the simulation effect of ground tests and the engine's operational adaptability.
Patent Information
- Application Number
- CN202511721779.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-21
- Publication Date
- 2026-02-17
- Estimated Expiration
- 2045-11-21
AI Technical Summary
Existing technologies make it difficult to effectively verify the working state of a hydrogen-oxygen engine under high-temperature inlet conditions before it is started, especially since the liquid hydrogen and liquid oxygen temperatures are low during ground tests, making it impossible to truly simulate actual flight conditions.
By controlling the tank pressure and maintaining pressure for static temperature recovery, and utilizing heat leakage from the walls and heat exchange from the air cushion, the propellant temperature inside the tank is gradually increased and stabilized at the target temperature, thereby achieving active control of the liquid hydrogen and liquid oxygen temperatures and ensuring that the engine starts and operates under high-temperature inlet conditions.
Precise control of liquid hydrogen and liquid oxygen temperatures was achieved. Ground test conditions were used to simulate actual flight conditions, verifying the engine's adaptability to operation under high-temperature inlet conditions and improving the authenticity and reliability of the test.
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Figure CN121539408A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a method for controlling and testing high-temperature inlet conditions of hydrogen pumps and / or oxygen pumps, belonging to the field of liquid rocket engine technology. Background Technology
[0002] Liquid rocket engines using hydrogen and oxygen as propellants have long been favored by the aerospace industry worldwide due to their high performance and lack of pollution. To date, dozens of different types of hydrogen-oxygen rocket engines have been developed and are widely used in the aerospace field. Because both liquid hydrogen and liquid oxygen are cryogenic propellants, the hydrogen and oxygen pumps need to be pre-cooled before starting the hydrogen-oxygen engine to ensure their proper functioning. Furthermore, the inlet pressure of the hydrogen and oxygen pumps must be within a certain range above their saturated vapor pressure to ensure the propellant remains liquid. The saturated vapor pressure of the propellant is related to the liquid temperature; the higher the liquid temperature, the higher the saturated vapor pressure.
[0003] Before rocket flight, liquid hydrogen and liquid oxygen are added to the rocket's propellant tanks at a pressure slightly higher than the local atmospheric pressure. The temperatures of the liquid hydrogen and liquid oxygen are approximately 21.5 K and 92 K, respectively. Before liftoff, the tanks are pressurized to their operating pressure. During flight, due to continuous heat input from aerodynamic heating, solar radiation, heat leakage from the tanks and pipelines, and heat exchange between the gas cushion and the liquid, the temperatures of the liquid hydrogen and liquid oxygen increase with the length of flight. Especially after prolonged coasting, when the engine needs to ignite again, it must start under conditions where both the hydrogen and oxygen pumps have high-temperature inlet conditions.
[0004] During ground tests, the storage tanks are generally vacuum-insulated tanks with double-layered vacuum-insulated pipes. The time between the completion of liquid hydrogen and liquid oxygen refueling and engine ignition is often very short, resulting in lower liquid hydrogen and liquid oxygen temperatures during ground tests compared to flight tests. This makes it difficult to effectively verify the engine's operating status under high-temperature inlet conditions of the hydrogen and oxygen pumps. Summary of the Invention
[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and enable the hydrogen-oxygen engine to start and perform operational testing under high-temperature pump inlet conditions, thereby verifying the operational adaptability of the hydrogen-oxygen engine under actual flight conditions.
[0006] The objective of this invention is achieved through the following technical solutions:
[0007] In a first aspect, the present invention provides a method for controlling and testing high-temperature inlet conditions of a hydrogen pump and / or an oxygen pump, comprising:
[0008] By charging and discharging the tank, the tank pressure is maintained at the saturated vapor pressure corresponding to the target temperature. By allowing the tank to stand still for a long time, the propellant temperature inside the tank is gradually increased and stabilized at the target temperature through heat leakage from the tank wall and heat exchange between the gas pillow and the liquid. Before starting, after the hydrogen tank is pressurized to the rated pressure, the engine begins to pre-cool. Once the inlet reaches the target temperature, the engine can be started.
[0009] Based on the first aspect, in one embodiment of the present invention, the high-temperature inlet temperatures Tr and Ty of the hydrogen pump and / or oxygen pump are determined, and then the physical property parameters of liquid hydrogen and liquid oxygen are queried to determine the saturated vapor pressure of hydrogen and / or the saturated vapor pressure of oxygen Prs and Pys.
[0010] Based on the first aspect, in one embodiment of the present invention, the pressure control range of the hydrogen tank and / or the pressure control range of the oxygen tank are determined according to the saturated vapor pressure and the tank pressure control accuracy of the test bench.
[0011] Based on the first aspect, in one embodiment of the present invention, the hydrogen storage tank and / or oxygen storage tank are subjected to pressure holding and static temperature recovery, and the liquid hydrogen and liquid oxygen inside the tank are continuously heated by external heat leakage.
[0012] Based on the first aspect, in one embodiment of the present invention, the liquid temperatures Trl and Tyl in the hydrogen and oxygen tanks are monitored in real time. After determining that the test requirements are met based on the measured liquid temperatures in the tanks, the hydrogen and / or oxygen tanks are pressurized to the working pressure.
[0013] Based on the first aspect, in one embodiment of the present invention, after liquid hydrogen is added to the storage tank, the hydrogen tank is pressurized and allowed to stand and warm up, with the tank pressure controlled within the range of 0.265 to 0.270 MPa.
[0014] Based on the first aspect, in one embodiment of the present invention, the pressure control accuracy of the hydrogen tank does not exceed 0.005 MPa. After liquid hydrogen is added to the storage tank, the hydrogen tank is pressure-maintained and allowed to cool down, with the tank pressure controlled within the range of 0.265 to 0.270 MPa.
[0015] In a second aspect, the present invention provides a computer-readable storage medium having stored thereon computer program instructions, which, when loaded and run by a processor, cause the processor to perform the method described in the first aspect.
[0016] Thirdly, the present invention provides an electronic device, comprising:
[0017] Processor; and
[0018] Memory is used to store computer program instructions;
[0019] When the computer program instructions are loaded and run by the processor, the processor performs the method described in the first aspect.
[0020] Compared with the prior art, the present invention has the following advantages:
[0021] (1) This invention overcomes the problem of not being able to directly control the temperature of liquid hydrogen and liquid oxygen in the storage tank, makes full use of existing experimental conditions, realizes active control of the temperature of liquid hydrogen and liquid oxygen, and achieves the purpose of controlling the high temperature inlet conditions of hydrogen and oxygen pumps and conducting experiments.
[0022] (2) Based on the physical properties of liquid hydrogen and liquid oxygen, this invention can control the temperature of liquid hydrogen and liquid oxygen in the tank relatively accurately by controlling the tank pressure and holding the pressure and allowing it to recover temperature. It does not require an additional temperature control system, is economical, and is easy to operate.
[0023] (3) The method of the present invention enables the hydrogen and oxygen pump inlet conditions of the engine ground test to be closer to the actual flight conditions, and can more realistically verify the working state of the engine under high temperature inlet conditions, expose potential problems in advance, and improve the ground test capability.
[0024] (4) The present invention is also applicable to the control of high temperature inlet conditions for cryogenic propellants such as liquid methane and liquid nitrogen, and can be extended to other test scenarios. Attached Figure Description
[0025] Figure 1 This is a schematic diagram of the high-temperature inlet condition control and test process for hydrogen pumps and / or oxygen pumps. Detailed Implementation
[0026] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.
[0027] Due to the physical properties of cryogenic propellants, the test rig cannot directly control the temperature of the propellant in the tank according to the test requirements. Based on the existing test conditions, the physical relationship between propellant temperature and saturated vapor pressure is utilized to actively control the tank pressure and maintain the pressure for temperature recovery, thereby achieving active control of the propellant temperature.
[0028] To achieve target temperature control of the hydrogen and oxygen pump inlet conditions, a method for controlling and testing high-temperature inlet conditions of the hydrogen and / or oxygen pumps is proposed. This method involves maintaining the tank pressure near the saturated vapor pressure corresponding to the target temperature through the charging and discharging of the storage tank. By employing a prolonged static state, heat leakage from the tank walls and heat exchange between the gas cushion and the liquid are utilized to gradually increase and stabilize the propellant temperature within the tank near the target temperature. Before startup, after the hydrogen tank is pressurized to its rated pressure, the engine begins pre-cooling. Start-up is possible once the inlet temperature reaches the target temperature.
[0029] like Figure 1 As shown, the specific steps include the following:
[0030] (1) Determine the high-temperature inlet temperatures Tr and Ty of the hydrogen pump and / or oxygen pump, such as Tr = 24K, Ty = 97K;
[0031] (2) Query the physical properties of liquid hydrogen and liquid oxygen to determine the saturated vapor pressure of hydrogen and / or the saturated vapor pressure of oxygen, Prs and Pys, such as Prs = 0.2648 MPa and Pys = 0.1958 MPa;
[0032] (3) Based on the saturated vapor pressure and the pressure control accuracy of the test bench, determine the pressure control range of the hydrogen tank and / or the pressure control range of the oxygen tank, which are: Prx = 0.265~0.270MPa, Pyx = 0.196~0.201MPa, respectively;
[0033] (4) The hydrogen storage tank and / or oxygen storage tank are pressure-maintained and allowed to stand still to recover temperature. The external heat leakage is used to make the liquid hydrogen and liquid oxygen in the tank continuously rise in temperature. As the tank pressure is stable, the liquid hydrogen and liquid oxygen will eventually stabilize at around the target temperature.
[0034] (5) Monitor the liquid temperatures Trl and Tyl in the hydrogen and oxygen tanks in real time. After determining that the test requirements are met based on the measured liquid temperatures in the tanks, pressurize the hydrogen tank and / or oxygen tank to the working pressure, which are: Prp = 0.35~0.355MPa and Pyp = 0.35~0.355MPa, respectively.
[0035] (6) After the engine enters the pre-cooling process and is pre-cooled, conduct high-temperature inlet start-up and operation tests of the hydrogen pump and / or oxygen pump.
[0036] Example:
[0037] Taking the high-temperature inlet operation adaptability test of the hydrogen pump as an example, the starting and operation adaptability of the hydrogen-oxygen engine under the 24K high-temperature inlet condition of the hydrogen pump is verified. The specific procedure is as follows:
[0038] (1) According to the test requirements of liquid hydrogen at 24K high temperature inlet, the physical property parameters of liquid hydrogen can be found that the saturated vapor pressure of liquid hydrogen at 24K is 0.2648MPa. Therefore, the pressure holding pressure of the hydrogen tank should not be lower than 0.2648MPa.
[0039] (2) The pressure control accuracy of the hydrogen tank is 0.005MPa. After liquid hydrogen is added to the storage tank, the hydrogen tank is kept under pressure and allowed to cool down. The tank pressure is controlled within the range of 0.265 to 0.270MPa.
[0040] (3) After standing and warming up for a certain period of time, the liquid hydrogen in the hydrogen tank continues to heat up due to the continuous input of external heat into the liquid hydrogen. The temperature of the liquid hydrogen is monitored in real time by the temperature sensor in the hydrogen tank.
[0041] (4) When the liquid hydrogen temperature reaches 24K, the hydrogen tank is pressurized to the working pressure of 0.35-0.355MPa, and the engine begins to pre-cool. When the hydrogen pump inlet temperature is pre-cooled to 24K, the engine is ignited and started to test the starting and working adaptability under high temperature hydrogen inlet.
[0042] The contents not described in detail in this specification are common knowledge to those skilled in the art.
[0043] 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.
Claims
1. A method of hydrogen pump and / or oxygen pump high temperature inlet condition control and testing, characterized by, It includes: By filling and discharging the tank, the tank pressure is maintained at the target temperature corresponding to the saturated vapor pressure, and the long time standing is used to gradually increase the temperature of the propellant in the tank and stabilize it at the target temperature by using the wall heat leakage of the tank and the heat exchange between the air pillow and the liquid; before starting, the hydrogen tank is pressurized to the rated pressure, and then the engine starts pre-cooling, and the inlet reaches the target temperature, and then the engine can be started.
2. The hydrogen pump and / or oxygen pump high temperature inlet condition control and testing method of claim 1, wherein, Determine the high temperature inlet temperature Tr and Ty of the hydrogen pump and / or oxygen pump, then query the physical property parameters of liquid hydrogen and liquid oxygen, and determine the hydrogen saturated vapor pressure and / or oxygen saturated vapor pressure Prs and Pys.
3. The hydrogen pump and / or oxygen pump high temperature inlet condition control and testing method of claim 1, wherein, According to the saturated vapor pressure and the tank pressure control accuracy of the test bench, the hydrogen tank pressure control range and / or oxygen tank pressure control range are determined.
4. The hydrogen pump and / or oxygen pump high temperature inlet condition control and testing method of claim 1, wherein, The hydrogen tank and / or oxygen tank are subjected to pressure maintaining and standing to restore temperature, and the external heat leakage is used to continuously warm up the liquid hydrogen and liquid oxygen in the tank.
5. The hydrogen pump and / or oxygen pump high temperature inlet condition control and testing method of claim 1, wherein, Real-time monitoring of the liquid temperature Trl and Tyl in the hydrogen tank and / or oxygen tank, and after the measured liquid temperature in the tank meets the test requirements, the hydrogen tank and / or oxygen tank is pressurized to the working pressure.
6. The hydrogen pump and / or oxygen pump high temperature inlet condition control and testing method of claim 1, wherein, After the liquid hydrogen is filled into the tank, the hydrogen tank is subjected to pressure maintaining and standing to restore temperature, and the tank pressure is controlled in the range of 0.265-0.270 MPa.
7. The hydrogen pump and / or oxygen pump high temperature inlet condition control and testing method of claim 1, wherein, The hydrogen tank pressure control accuracy is not more than 0.005 MPa, and after the liquid hydrogen is filled into the tank, the hydrogen tank is subjected to pressure maintaining and standing to restore temperature, and the tank pressure is controlled in the range of 0.265-0.270 MPa.
8. A computer readable storage medium having stored thereon computer program instructions, which when loaded and run by a processor, cause the processor to execute the method of any one of claims 1 to 7.
9. An electronic device comprising: a processor; and a memory for storing computer program instructions; wherein when the computer program instructions are loaded and run by the processor, the processor executes the method of any one of claims 1 to 7.
Citation Information
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