A non-destructive in-orbit refueling system and method for cryogenic propellants

Abstract

The present invention discloses a non-destructive in-orbit refueling system and method for cryogenic propellants. The system includes a cryogenic refueling tank internally provided with a high-thermal-conductivity porous medium supercharger. An electric heater is installed at the upper end of the supercharger. The cryogenic refueling tank is connected to a cryogenic liquid circulation pump through a pipeline provided with a stop valve. The cryogenic liquid circulation pump is connected to a refueling tank infusion pipeline provided with a temperature sensor. The refueling tank infusion pipeline is connected to a receiving tank infusion pipeline provided with a stop valve. The receiving tank infusion pipeline is connected to a cryogenic receiving tank. The cryogenic receiving tank is equipped with a temperature sensor and a pressure sensor and is connected to a receiving tank gas pipeline provided with a stop valve. The receiving tank gas pipeline is connected to a refueling tank gas pipeline provided with a stop valve. The cryogenic refueling tank is equipped with a pressure sensor. The propellant vapor discharged from the cryogenic refueling tank and the cryogenic receiving tank is compressed by a compressor and then stored in a high-pressure gas tank for pressurizing the cryogenic refueling tank, realizing self-pressurizing small-flow pre-cooling and non-destructive refueling of cryogenic propellants.

Description

Technical Field

[0001] The invention belongs to the field of on-orbit propellant filling, and particularly relates to a non-destructive cryogenic propellant on-orbit filling system and method. Background Art

[0002] In space technology, on-orbit propellant topping up is an effective means to extend the operation time limit of spacecraft and expand the scope of space exploration. Large-scale and long-term on-orbit missions will rely on the support of on-orbit propellant filling technology. For a propulsion system using chemical propellants, the propellant carrying capacity directly limits the working cycle and exploration scope of space missions. At present, the on-orbit transfer and topping-up technology of normal-temperature propulsion systems has been relatively mature. In particular, the extrusion and exhaust filling system based on bladder tanks has been successfully applied in many on-orbit missions.

[0003] Cryogenic propellants such as liquid hydrogen and liquid oxygen have excellent performance characteristics of high specific impulse, non-toxic and pollution-free, and have become the preferred propellants for large-scale space missions such as future deep space exploration and space bases. However, compared with normal-temperature propellants, cryogenic propellants have problems such as low temperature, low boiling point, easy evaporation and difficult storage, which bring many severe challenges to the on-orbit topping-up process, resulting in the inapplicability of normal-temperature propulsion systems to the on-orbit filling of cryogenic propellants, manifested in: on the one hand, cryogenic propellants need to be strictly pre-cooled before starting the transfer and topping-up, otherwise it will cause abnormal pressure in the filling system, leading to the inability to smoothly carry out the filling process; on the other hand, the exhaust filling will cause the emission loss of propellant vapor, resulting in the waste of propellant energy; on the other hand, the existing normal-temperature propulsion systems cannot perform gas-liquid separation, so they are not applicable to cryogenic propellants that are easy to evaporate.

[0004] China's cryogenic propellant on-orbit filling technology is still in the initial research stage, and no practical on-orbit application plan has been formed. In order to accelerate the development of cryogenic propellant on-orbit filling technology and support the research and implementation of future large-scale space missions, it is urgent to develop an on-orbit filling system that can solve the problems of on-orbit gas-liquid separation, efficient pre-cooling and non-destructive filling of cryogenic propellants, so as to improve the reliability, safety and economy of the on-orbit filling process of cryogenic propellants, and thus promote the smooth research and implementation of future large-scale space projects. Summary of the Invention

[0005] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a non-destructive cryogenic propellant on-orbit filling system and method, which realizes the non-destructive filling of cryogenic propellants without additional pressurization devices.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions to be realized:

[0007] A non-destructive cryogenic propellant on-orbit filling system includes a cryogenic filling tank, a high thermal conductivity porous medium pressurizer, a compressor and a cryogenic receiving tank;

[0008] The low-temperature filling tank is divided into a gas phase region and a liquid phase region from top to bottom in sequence. The high-thermal-conductivity porous medium booster is fixedly installed inside the low-temperature filling tank, and the upper and lower ends of the high-thermal-conductivity porous medium booster are respectively located in the gas phase region and the liquid phase region. An electric heater for heating it is installed at the upper end of the high-thermal-conductivity porous medium booster;

[0009] The bottom of the low-temperature filling tank is connected to the inlet of the low-temperature liquid circulation pump through a first pipeline. A first liquid stop valve is installed on the first pipeline. The outlet of the low-temperature liquid circulation pump is connected to the filling tank infusion pipeline, and a first temperature sensor is installed on the filling tank infusion pipeline;

[0010] The filling tank infusion pipeline is connected to the recipient tank infusion pipeline through a liquid pipeline quick-connect interface. A second liquid stop valve is installed on the recipient tank infusion pipeline, and the recipient tank infusion pipeline is connected to the bottom of the low-temperature recipient tank. A second temperature sensor and a second pressure sensor are installed on the top of the low-temperature recipient tank;

[0011] The top of the low-temperature recipient tank is connected to a recipient tank gas pipeline. A third gas stop valve is installed on the recipient tank gas pipeline. The recipient tank gas pipeline is connected to the filling tank gas pipeline through a gas pipeline quick-connect interface. A fourth gas stop valve is installed on the filling tank gas pipeline;

[0012] A first pressure sensor and a fourth pipeline are installed on the top of the low-temperature filling tank. A solenoid valve is installed on the fourth pipeline, and the solenoid valve is connected to the first pressure sensor;

[0013] Both the fourth pipeline and the filling tank gas pipeline are connected to the inlet of the compressor. The outlet of the compressor is connected to the inlet of the high-pressure gas tank through a second pipeline. A first gas stop valve is installed on the second pipeline. The outlet of the high-pressure gas tank is connected to the top of the low-temperature filling tank through a third pipeline to deliver high-pressure gas to the gas phase region. A second gas stop valve is installed on the third pipeline.

[0014] Furthermore, a vapor cooling coil is fixedly installed on the outer side wall of the low-temperature filling tank. The inlet of the vapor cooling coil is respectively connected to the fourth pipeline and the filling tank gas pipeline. The outlet of the vapor cooling coil is connected to the inlet of the compressor through a fifth pipeline.

[0015] Furthermore, a liquid collector is installed at the inner bottom of the low-temperature filling tank. The liquid collector is located in the liquid phase region, and the liquid collector is of a mesh channel structure;

[0016] The outlet of the liquid collector is connected to the inlet of the low-temperature liquid circulation pump through a first pipeline.

[0017] Furthermore, the high-thermal-conductivity porous medium booster is a porous medium structure made of a high-thermal-conductivity material, and stores liquid propellant through the capillary action of internal pores.

[0018] Furthermore, the external power supplies of the electric heater, the cryogenic liquid circulation pump and the compressor are all solar power supplies.

[0019] Furthermore, the solar power supply includes a first solar power supply for powering the cryogenic liquid circulation pump, a second solar power supply for powering the electric heater, and a third solar power supply for powering the compressor.

[0020] A method for on-orbit refueling of cryogenic propellants includes the following steps:

[0021] Step 1, On-orbit storage

[0022] When the first pressure sensor monitors that the pressure in the cryogenic refueling tank reaches the preset upper limit value, the solenoid valve is opened. The cryogenic propellant vapor in the cryogenic refueling tank enters the compressor through the fourth pipeline, is compressed, and then flows into the high-pressure gas tank through the second pipeline for storage; when the first pressure sensor monitors that the pressure in the cryogenic refueling tank drops to the preset safe range, the solenoid valve is closed;

[0023] Step 2, Electrothermal self-pressurization continuous precooling

[0024] Open the first liquid stop valve, the second liquid stop valve, the first gas stop valve, the third gas stop valve and the fourth gas stop valve, close the solenoid valve and the second gas stop valve, and do not start the cryogenic liquid circulation pump. Under the heating of the electric heater, the cryogenic liquid propellant remaining inside the high thermal conductivity porous medium supercharger continuously evaporates, causing the pressure in the gas phase region to continuously increase, realizing self-pressurization of the cryogenic refueling tank. Under the action of pressure drive, the cryogenic liquid propellant in the liquid phase region sequentially flows through the first liquid stop valve, the cryogenic liquid circulation pump, the refueling tank liquid delivery pipeline, the liquid pipeline quick connection interface, the receiving tank liquid delivery pipeline and the second liquid stop valve, and enters the cryogenic receiving tank to achieve precooling; the propellant vapor gasified by heat inside the cryogenic receiving tank sequentially passes through the third gas stop valve, the receiving tank gas pipeline, the gas pipeline quick connection interface, the refueling tank gas pipeline and the fourth gas stop valve, enters the compressor, is compressed, and then flows into the high-pressure gas tank through the second pipeline for storage;

[0025] Step 3, Recycling self-pressurization intermittent precooling

[0026] When the first temperature sensor and the second temperature sensor detect that the temperatures of the infusion pipeline of the filling tank and the cryogenic receiving tank drop to the preset value, keep the first liquid stop valve and the second liquid stop valve in the open state, open the second gas stop valve, close the first gas stop valve, the third gas stop valve, the fourth gas stop valve and the solenoid valve, and the high thermal conductivity porous medium supercharger continues to work, pushing the cryogenic liquid propellant in the liquid phase region to the cryogenic receiving tank continuously. At the same time, the high-pressure gas in the high-pressure gas tank enters the gas phase region through the second gas stop valve to perform supplementary self-pressurization on the cryogenic filling tank and increase the precooling flow rate;

[0027] When the precooling filling time reaches the set value, turn off the electric heater, the first liquid stop valve, the second liquid stop valve, the second gas stop valve, the first gas stop valve, the third gas stop valve, the fourth gas stop valve, the solenoid valve and the compressor, and the cryogenic liquid propellant inside the cryogenic receiving tank exchanges heat with the original propellant and the wall of the cryogenic receiving tank in the cryogenic receiving tank;

[0028] When the second pressure sensor detects that the pressure in the cryogenic receiving tank reaches the preset upper pressure limit, turn on the compressor, the first gas stop valve, the third gas stop valve and the fourth gas stop valve. The cryogenic propellant vapor discharged from the cryogenic receiving tank flows through the third gas stop valve, the receiving tank gas pipeline, the gas pipeline quick-connect interface, the filling tank gas pipeline and the fourth gas stop valve in sequence, enters the compressor and is compressed, and then flows into the high-pressure gas tank for storage through the second pipeline;

[0029] When the second pressure sensor detects that the pressure in the cryogenic receiving tank drops to the preset safe range, turn off the compressor, the first gas stop valve, the third gas stop valve and the fourth gas stop valve, turn on the electric heater, the first liquid stop valve, the second liquid stop valve and the second gas stop valve, and perform precooling filling again; repeat this process to perform recovery self-pressurization intermittent precooling;

[0030] Step 4, pump-driven non-exhaustive filling

[0031] When the first temperature sensor detects that the temperature of the infusion pipeline of the filling tank is precooled to the liquid temperature zone and the second temperature sensor detects that the temperature of the cryogenic receiving tank reaches the precooling target temperature, turn on the cryogenic liquid circulation pump, the first liquid stop valve, the second liquid stop valve, turn off the electric heater, the second gas stop valve, the first gas stop valve, the third gas stop valve, the fourth gas stop valve, the compressor and the solenoid valve. Driven by the cryogenic liquid circulation pump, the cryogenic propellant is transferred from the cryogenic filling tank to the cryogenic receiving tank, and during the transfer process, the cryogenic receiving tank never exhausts gas, realizing non-destructive on-orbit filling of the cryogenic propellant.

[0032] Further, step 1 further includes that the cryogenic propellant vapor in the cryogenic filling tank first enters the vapor cooling coil through the fourth pipeline, then flows out of the vapor cooling coil and enters the compressor through the fifth pipeline.

[0033] Further, step 2 further includes that the cryogenic propellant vapor discharged from the cryogenic receiving tank first enters the vapor cooling coil through the filling tank gas pipeline, and then flows into the compressor through the fifth pipeline.

[0034] Compared with the prior art, the present invention has the following technical effects:

[0035] The present invention combines self-pressurizing liquid-driven small-flow precooling with circulating pump liquid-driven large-flow filling, realizing the safe and efficient progress of the in-orbit filling process of cryogenic propellants, significantly reducing the scale of the pressurized gas module, and not requiring the supply and replenishment of additional pressurized gas compared with non-condensable gas pressurization. At the same time, during the precooling process, the propellant vapor is recycled, realizing the lossless filling of the propellant, specifically reflected in: First, in the initial stage of precooling, an electric heater is used to heat the porous medium supercharger, heating and vaporizing the cryogenic propellant stored in the porous medium supercharger, realizing the self-pressurization of the cryogenic filling tank without the need for other external pressurization modules, making the structure simple and the energy loss small; Second, in the middle and late stages of precooling, a large amount of propellant vapor generated during the precooling process of the receiving tank is recovered to the pressurized gas tank by the compressor and then transported to the cryogenic filling tank to supplement the self-pressurization of the cryogenic filling tank, realizing a larger-flow system precooling under the condition of propellant lossless recovery; Third, when the filling system is completed with precooling, a non-exhaust rapid filling of the receiving tank is carried out by the circulating pump, realizing the lossless filling of the cryogenic propellant. It can be seen that the present invention can make full use of a small flow of cryogenic propellant to perform in-orbit self-pressurizing precooling on the system, thereby realizing the lossless in-orbit filling of cryogenic propellants.

[0036] The vapor cooling coil is used to recover the propellant heated and vaporized inside the cryogenic filling tank and the cryogenic receiving tank, and the cryogenic propellant vapor plays a thermal protection role for the cryogenic filling tank, effectively reducing the heat exchange between the propellant inside the cryogenic filling tank and the external environment, not only realizing the recovery and utilization of the cold energy of the propellant, but also reducing the system energy consumption.

[0037] By installing a liquid collector with a mesh channel structure at the bottom inside the cryogenic filling tank, single-phase liquid propellant can be obtained under microgravity conditions through the capillary force and surface tension of the porous metal mesh, effectively realizing gas-liquid separation and improving the operation stability of the system.

[0038] The solar power supply is used to supply power to the heater, compressor and circulating pump respectively, making full use of the solar radiation in the space environment and improving the stability and economy of the sustainable operation of the filling system. Description of the Drawings

[0039] Figure 1 : Schematic structural diagram of the present invention;

[0040] In the figure: 1, low-temperature filling tank; 2, gas phase region; 3, liquid phase region; 4, liquid collector; 5, first liquid shut-off valve; 6, low-temperature liquid circulation pump; 7, first switch; 8, first solar power source; 9, high thermal conductivity porous medium booster; 10, electric heater; 11, second switch; 12, second solar power source; 13, first pressure sensor; 14, solenoid valve; 15, vapor cooling coil; 16, compressor; 17, third switch; 18, third solar power source; 19, first gas shut-off valve; 20, high-pressure gas tank; 21, second gas shut-off valve; 22, first temperature sensor; 23, filling tank liquid delivery pipeline; 24, liquid pipeline quick-connect interface; 25, receiving tank liquid delivery pipeline; 26, second liquid shut-off valve; 27, low-temperature receiving tank; 28, second temperature sensor; 29, second pressure sensor; 30, third gas shut-off valve; 31, receiving tank gas pipeline; 32, gas pipeline quick-connect interface; 33, filling tank gas pipeline; 34, fourth gas shut-off valve; 35, first pipeline; 36, second pipeline; 37, third pipeline; 38, fourth pipeline; 39, fifth pipeline. Specific embodiments

[0041] The following further elaborates on the specific content of the present invention in conjunction with embodiments.

[0042] As Figure 1 shown, a non-destructive in-orbit filling system for cryogenic propellants includes a low-temperature filling tank 1, a high thermal conductivity porous medium booster 9, and a low-temperature receiving tank 27.

[0043] The low-temperature filling tank 1 is sequentially divided into a gas phase region 2 and a liquid phase region 3 from top to bottom. The high thermal conductivity porous medium booster 9 is fixedly installed inside the low-temperature filling tank 1, and the upper and lower ends of the high thermal conductivity porous medium booster 9 are respectively located in the gas phase region 2 and the liquid phase region 3. The upper end of the high thermal conductivity porous medium booster 9 is connected to an electric heater 10. The electric heater 10 is connected to the second solar power source 12 through a second wire, so as to supply power to the electric heater 10 using the second solar power source 12. The second wire is connected to a second switch 11, and the circuit connecting the second solar power source 12 and the electric heater 10 is cut off or connected through the second switch 11.

[0044] The high thermal conductivity porous medium booster 9 is a porous medium structure made of high thermal conductivity materials. It realizes the wicking and storage of liquid propellant through internal pores. Therefore, the lower end of the high thermal conductivity porous medium booster 9 is always in the liquid phase region 3, thus maintaining a wet state. The liquid propellant stored inside it is continuously evaporated under the heating of the electric heater 10, causing the pressure in the gas phase region 2 to continuously increase, thereby realizing the self-pressurization inside the cryogenic filling tank 1;

[0045] A liquid collector 4 is installed at the bottom inside the cryogenic filling tank 1. The liquid collector 4 is located in the liquid phase region 3. The outlet of the liquid collector 4 is connected to the inlet of the cryogenic liquid circulation pump 6 through a first pipeline 35, and a first liquid stop valve 5 is installed on the first pipeline 35. The outlet of the cryogenic liquid circulation pump 6 is connected to a filling tank infusion pipeline 23. A first temperature sensor 22 is installed on the filling tank infusion pipeline 23. The filling tank infusion pipeline 23 is connected to the recipient tank infusion pipeline 25 through a liquid pipeline quick connection interface 24. A second liquid stop valve 26 is installed on the recipient tank infusion pipeline 25, and the recipient tank infusion pipeline 25 is connected to the bottom of the cryogenic recipient tank 27. A second temperature sensor 28 and a second pressure sensor 29 are installed on the top of the cryogenic recipient tank 27;

[0046] The liquid collector 4 is a screen channel structure. It obtains single-phase liquid propellant under microgravity conditions through the capillary force and surface tension of the porous metal screen. The single-phase liquid propellant, under the action of pressure drive, flows through the first cryogenic liquid stop valve 5, the cryogenic liquid circulation pump 6, the filling tank infusion pipeline 23, the liquid pipeline quick connection interface 24, the recipient tank infusion pipeline 25, and the second liquid stop valve 26 in sequence and enters the cryogenic recipient tank 27;

[0047] The cryogenic liquid circulation pump 6 is connected to the first solar power source 8 through a first wire, so as to use the first solar power source 8 to supply power to the cryogenic liquid circulation pump 6. The first wire is connected with a first switch 7, and the circuit connecting the first solar power source 8 and the cryogenic liquid circulation pump 6 is cut off or connected through the first switch 7;

[0048] The top of the cryogenic recipient tank 27 is connected with a recipient tank gas pipeline 31. A third gas stop valve 30 is installed on the recipient tank gas pipeline 31. The recipient tank gas pipeline 31 is connected to the filling tank gas pipeline 33 through a gas pipeline quick connection interface 32. A fourth gas stop valve 34 is installed on the filling tank gas pipeline 33. The filling tank gas pipeline 33 is connected to the vapor cooling coil 15. The propellant vapor heated and vaporized inside the cryogenic recipient tank 27 passes through the third gas stop valve 30, the recipient tank gas pipeline 31, the gas pipeline quick connection interface 32, the filling tank gas pipeline 33, and the fourth gas stop valve 34 in sequence and enters the vapor cooling coil 15. After the cold energy recovery is completed;

[0049] The vapor cooling coil 15 is installed on the outer wall of the cryogenic filling tank 1. The outlet of the vapor cooling coil 15 is connected to the inlet of the compressor 16 through the fifth pipeline 39. The outlet of the compressor 16 is connected to the inlet of the high-pressure gas tank 20 through the second pipeline 36. A first gas shut-off valve 19 is installed on the second pipeline 36. The outlet of the high-pressure gas tank 20 is connected to the top of the cryogenic filling tank 1 through the third pipeline 37 to deliver high-pressure gas to the gas phase area 2. And a second gas shut-off valve 21 is installed on the third pipeline 37. The propellant inside the vapor cooling coil 15 flows into the compressor 16 through the fifth pipeline 39. After being compressed, it is stored in the high-pressure gas tank 20. The high-pressure gas in the high-pressure gas tank 20 enters the gas phase area 2 of the filling tank through the second gas shut-off valve 21 to perform supplementary self-pressurization on the cryogenic filling tank 1 and increase the precooling flow rate;

[0050] The compressor 16 is connected to the third solar power source 18 through the third wire, so as to supply power to the compressor 16 by using the third solar power source 18. The third wire is connected with a third switch 17, and the circuit connecting the third solar power source 18 and the compressor 16 is cut off or connected through the third switch 17;

[0051] A first pressure sensor 13 and a fourth pipeline 38 are installed on the top of the cryogenic filling tank 1. The fourth pipeline 38 is connected with a solenoid valve 14 and is connected to the vapor cooling coil 15. The solenoid valve 14 is connected to the first pressure sensor 13. The internal pressure of the cryogenic filling tank 1 is monitored by the first pressure sensor 13 and the signal is fed back to the solenoid valve 14. When the first pressure sensor 13 monitors that the pressure in the cryogenic filling tank 1 reaches the preset upper limit value, the solenoid valve 14 is opened for exhaust pressure relief. The propellant vapor is recovered in the vapor cooling coil 15 and plays a thermal protection role for the cryogenic filling tank 1, effectively preventing the continuous leakage of heat in space from causing the continuous temperature rise and gasification of the cryogenic propellant in the cryogenic filling tank 1. The heated propellant vapor in the vapor cooling coil 15 is compressed by the compressor 16 and then flows into the high-pressure gas tank 20 through the second pipeline 36 for storage; otherwise, when the first pressure sensor 13 monitors that the pressure in the cryogenic filling tank 1 drops to the preset safe range, the solenoid valve 14 is closed.

[0052] A non-destructive on-orbit filling method for cryogenic propellants includes on-orbit storage, electrothermal self-pressurization continuous precooling, recovery self-pressurization intermittent precooling, and pump-driven non-exhaust filling. The specific process is as follows:

[0053] 1), On-orbit storage

[0054] During the process of filling cryogenic propellant into the cryogenic filling tank 1 through the filling port, when the first pressure sensor 13 monitors that the pressure in the cryogenic filling tank 1 reaches the preset upper limit value, the solenoid valve 14 is opened for exhaust pressure relief. The discharged cryogenic propellant vapor enters the vapor cooling coil 15 through the fourth pipeline 38. The recovered cryogenic propellant vapor in the vapor cooling coil 15 plays a thermal protection role for the cryogenic filling tank 1. After the propellant vapor heated up in the vapor cooling coil 15 flows into the compressor 16 through the fifth pipeline 39 and is compressed, it flows into the high-pressure gas tank 20 through the second pipeline 36 for storage. When the first pressure sensor 13 monitors that the pressure in the cryogenic filling tank 1 drops to the preset safe range, the solenoid valve 14 is closed;

[0055] 2) Electrothermal self-pressurizing continuous precooling

[0056] First, quickly connect the filling tank infusion pipeline 23 with the receiving tank infusion pipeline 25 through the liquid pipeline quick-connect interface 24, and quickly connect the receiving tank gas pipeline 31 with the filling tank gas pipeline 33 through the gas pipeline quick-connect interface 32. Then, open the second switch 11, the third switch 17, the first liquid stop valve 5, the second liquid stop valve 26, the first gas stop valve 19, the third gas stop valve 30, and the fourth gas stop valve 34, and close the first switch 7, the solenoid valve 14, and the second gas stop valve 21. Since the lower end of the high thermal conductivity porous medium supercharger 9 is located in the liquid phase region 3, the high thermal conductivity porous medium supercharger 9 is in a wetting state. Under the heating of the electric heater 10, the continuously stored cryogenic liquid propellant inside the high thermal conductivity porous medium supercharger 9 evaporates continuously, causing the pressure in the gas phase region 2 to rise continuously, realizing the self-pressurization of the cryogenic filling tank 1. Under the action of pressure drive, the cryogenic liquid propellant in the liquid phase region 3 flows out through the liquid collector 4, successively flows through the first liquid stop valve 5, the cryogenic liquid circulation pump 6, the filling tank infusion pipeline 23, the liquid pipeline quick-connect interface 24, the receiving tank infusion pipeline 25, and the second liquid stop valve 26, and enters the cryogenic receiving tank 27, thereby precooling the first liquid stop valve 5, the cryogenic liquid circulation pump 6, the filling tank infusion pipeline 23, the liquid pipeline quick-connect interface 24, the receiving tank infusion pipeline 25, the second liquid stop valve 26, and the cryogenic receiving tank 27. The propellant vapor gasified by heat inside the cryogenic receiving tank 27 successively passes through the third gas stop valve 30, the receiving tank gas pipeline 31, the gas pipeline quick-connect interface 32, the filling tank gas pipeline 33, and the fourth gas stop valve 34, enters the vapor cooling coil 15. After the cold energy is recovered, it flows into the compressor 16 through the fifth pipeline 39, is compressed, and stored in the high-pressure gas tank 20;

[0057] In the initial stage of precooling, the filling system is at a relatively high initial temperature. The precooling flow rate of the cryogenic propellant should not be too large, otherwise the violent gas-liquid two-phase flow may cause system oscillation. Therefore, it is necessary to control the pressure inside the cryogenic filling tank 1 to adjust the flow rate of the liquid propellant;

[0058] 3) Recoverable self-pressurizing intermittent precooling

[0059] When the first temperature sensor 22 and the second temperature sensor 28 detect that the temperatures of the filling tank infusion pipeline 23 and the cryogenic receiving tank 27 drop to the preset values, the precooling flow rate of the cryogenic propellant can be appropriately increased, keeping the second switch 11, the first liquid stop valve 5 and the second liquid stop valve 26 still in the open state, opening the second gas stop valve 21, closing the first gas stop valve 19, the third gas stop valve 30, the fourth gas stop valve 34, the first switch 7, the third switch 17 and the solenoid valve 14, and the high thermal conductivity porous medium supercharger 9 continues to work, continuously conveying the cryogenic liquid propellant in the liquid phase region 3 to the cryogenic receiving tank 27. At the same time, the high-pressure gas in the high-pressure gas tank 20 enters the gas phase region 2 of the filling tank through the second gas stop valve 21 to supplement self-pressurization for the cryogenic filling tank 1 and increase the precooling flow rate;

[0060] When the precooling filling time reaches the set value, close the second switch 11, the first liquid stop valve 5, the second liquid stop valve 26, the second gas stop valve 21, the first gas stop valve 19, the third gas stop valve 30, the fourth gas stop valve 34, the first switch 7, the third switch 17 and the solenoid valve 14, and the cryogenic liquid propellant inside the cryogenic receiving tank 27 exchanges heat with the original propellant in the cryogenic receiving tank 27 and the wall surface of the cryogenic receiving tank 27;

[0061] When the second pressure sensor 29 detects that the pressure in the cryogenic receiving tank 27 reaches the preset upper pressure limit, open the third switch 17, the first gas stop valve 19, the third gas stop valve 30 and the fourth gas stop valve 34 for exhaust pressure relief. The discharged cryogenic vapor flows through the third gas stop valve 30, the receiving tank gas pipeline 31, the gas pipeline quick connection interface 32, the filling tank gas pipeline 33 and the fourth gas stop valve 34 in sequence, enters the vapor cooling coil 15 to complete cold recovery, and then flows into the compressor 16 through the fifth pipeline 39. After being compressed, it is stored in the high-pressure gas tank 20;

[0062] When the second pressure sensor 29 detects that the pressure in the cryogenic receiving tank 27 drops to the preset safe range, close the third switch 17, the first gas stop valve 19, the third gas stop valve 30 and the fourth gas stop valve 34, open the second switch 11, the first liquid stop valve 5, the second liquid stop valve 26 and the second gas stop valve 21, and perform precooling filling again; repeat this process to perform recoverable self-pressurizing intermittent precooling;

[0063] 4) Pump-driven non-exhaustive filling

[0064] When the first temperature sensor 22 monitors that the temperature of the infusion pipeline 23 of the filling tank has been precooled to the liquid temperature range, it indicates that the cryogenic liquid circulation pump 6 has been precooled to the liquid temperature range and can operate under the full-liquid condition. At the same time, when the second temperature sensor 28 monitors that the temperature of the cryogenic receiving tank 27 has reached the precooling target temperature, the pump-driven non-exhaust filling starts;

[0065] Open the first liquid stop valve 5, the first switch 7, and the second liquid stop valve 26, and close the second switch 11, the second gas stop valve 21, the first gas stop valve 19, the third gas stop valve 30, the fourth gas stop valve 34, the third switch 17, and the solenoid valve 14. Under the driving action of the cryogenic liquid circulation pump 6, the cryogenic propellant is transferred from the cryogenic filling tank 1 to the cryogenic receiving tank 27 at a large flow rate. During the filling process, the cryogenic receiving tank 27 never exhausts, and the internal pressure of the cryogenic receiving tank 27 is maintained at a low level through the phase change of the cryogenic propellant to achieve lossless transfer;

[0066] After the filling amount of the propellant inside the cryogenic receiving tank 27 reaches the target filling amount, close the first liquid stop valve 5, the first switch 7, the second liquid stop valve 26, the second switch 11, the second gas stop valve 21, the first gas stop valve 19, the third gas stop valve 30, the fourth gas stop valve 34, the first switch 7, the third switch 17, and the solenoid valve 14, and disconnect the quick-connect interface 24 of the liquid pipeline and the quick-connect interface 32 of the gas pipeline to complete the on-orbit filling of the cryogenic propellant.

Claims

1. A non-destructive cryogenic propellant on-orbit filling system, characterized in that: It comprises a low-temperature filling box (1), a high thermal conductivity porous medium supercharger (9), a compressor (16) and a low-temperature filling receiving box (27); The low temperature filling box (1) is divided into a gas phase region (2) and a liquid phase region (3) from top to bottom, and the high thermal conductivity porous medium booster (9) is fixedly installed inside the low temperature filling box (1), and the upper end and lower end of the high thermal conductivity porous medium booster (9) are respectively located in the gas phase region (2) and the liquid phase region (3), and an electric heater (10) for heating the high thermal conductivity porous medium booster (9) is installed at the upper end; The bottom of the low-temperature filling box (1) is connected to the inlet of the low-temperature liquid circulation pump (6) through a first pipeline (35), the first pipeline (35) is equipped with a first liquid stop valve (5), the outlet of the low-temperature liquid circulation pump (6) is connected to the filling box infusion pipeline (23), and the filling box infusion pipeline (23) is equipped with a first temperature sensor (22); The infusion pipeline (23) of the filling box is connected to the infusion pipeline (25) of the receiving box through a liquid pipeline quick-connect interface (24); the infusion pipeline (25) of the receiving box is equipped with a second liquid stop valve (26); the infusion pipeline (25) of the receiving box is connected to the bottom of the low-temperature receiving box (27); the top of the low-temperature receiving box (27) is equipped with a second temperature sensor (28) and a second pressure sensor (29); The top of the low-temperature injection receiving box (27) is connected to a gas pipeline (31) for the injection receiving box, the gas pipeline (31) for the injection receiving box is equipped with a third gas shut-off valve (30), the gas pipeline (31) for the injection receiving box is connected to a gas pipeline (33) for the injection filling box via a gas pipeline quick-connect interface (32), and the gas pipeline (33) for the injection filling box is equipped with a fourth gas shut-off valve (34); A first pressure sensor (13) and a fourth pipeline (38) are installed on the top of the low-temperature filling box (1); a solenoid valve (14) is installed on the fourth pipeline (38); and the solenoid valve (14) is connected to the first pressure sensor (13); The fourth pipeline (38) and the filling box gas pipeline (33) are both connected to the inlet of the compressor (16), the outlet of the compressor (16) is connected to the inlet of the high-pressure gas tank (20) through the second pipeline (36), the second pipeline (36) is equipped with a first gas shut-off valve (19), the outlet of the high-pressure gas tank (20) is connected to the top of the low-temperature filling box (1) through the third pipeline (37) so as to transport the high-pressure gas to the gas phase zone (2), and the third pipeline (37) is equipped with a second gas shut-off valve (21).

2. The non-destructive cryogenic propellant on-orbit filling system according to claim 1, characterized in that: A steam cooling coil (15) is fixedly mounted on the outer wall of the low-temperature filling box (1); the inlet of the steam cooling coil (15) is respectively connected to the fourth pipeline (38) and the filling box gas pipeline (33); and the outlet of the steam cooling coil (15) is connected to the inlet of the compressor (16) via a fifth pipeline (39).

3. The non-destructive cryogenic propellant on-orbit filling system according to claim 1 or 2, characterized in that: A liquid collector (4) is installed at the bottom of the low-temperature filling box (1), the liquid collector (4) is located in the liquid phase area (3), and the liquid collector (4) is a mesh curtain channel structure; The outlet of the liquid collector (4) is connected to the inlet of the low-temperature liquid circulation pump (6) through a first pipeline (35).

4. The non-destructive cryogenic propellant on-orbit filling system according to claim 1 or 2, characterized in that: The high thermal conductivity porous medium booster (9) is a porous medium structure made of a high thermal conductivity material, and liquid propellant is stored by the wicking effect of internal pores.

5. The non-destructive cryogenic propellant on-orbit filling system according to claim 1 or 2, characterized in that: The external power sources of the electric heater (10), the low-temperature liquid circulation pump (6) and the compressor (16) are all solar power sources.

6. The non-destructive cryogenic propellant on-orbit filling system according to claim 5, characterized in that: The solar power source comprises a first solar power source (8) for supplying power to a low-temperature liquid circulation pump (6), a second solar power source (12) for supplying power to an electric heater (10), and a third solar power source (18) for supplying power to a compressor (16).

7. A method for on-orbit refueling of cryogenic propellants based on the non-destructive cryogenic propellant on-orbit refueling system according to claim 2, characterized in that: The steps include: Step 1: On-orbit storage When the first pressure sensor (13) detects that the pressure in the cryogenic filling tank (1) reaches a preset upper limit value, the solenoid valve (14) is opened, and the cryogenic propellant vapor in the cryogenic filling tank (1) enters the compressor (16) through the fourth pipeline (38) and is compressed, and then flows into the high-pressure gas tank (20) through the second pipeline (36) for storage; when the first pressure sensor (13) detects that the pressure in the cryogenic filling tank (1) drops to a preset safety range, the solenoid valve (14) is closed; Step 2: Electric self-pressurization continuous precooling The first liquid stop valve (5), the second liquid stop valve (26), the first gas stop valve (19), the third gas stop valve (30) and the fourth gas stop valve (34) are opened, the solenoid valve (14) and the second gas stop valve (21) are closed, and the cryogenic liquid circulation pump (6) is not started. Under the heating of the electric heater (10), the cryogenic liquid propellant stored in the high thermal conductivity porous medium booster (9) is continuously evaporated, so that the pressure of the gas phase region (2) is continuously increased, and the self-pressurization of the cryogenic filling tank (1) is realized. Under the driving effect of the pressure, the cryogenic liquid propellant in the liquid phase region (3) flows through the first liquid stop valve (5) and the second gas stop valve (21) in sequence. (5), a low-temperature liquid circulation pump (6), a filling box infusion pipeline (23), a liquid pipeline quick-connect interface (24), a receiving box infusion pipeline (25) and a second liquid stop valve (26), and enters a low-temperature receiving box (27) to achieve pre-cooling; the propellant vapor heated and vaporized inside the low-temperature receiving box (27) passes through a third gas stop valve (30), a receiving box gas pipeline (31), a gas pipeline quick-connect interface (32), a filling box gas pipeline (33) and a fourth gas stop valve (34), enters a compressor (16) to be compressed, and then flows into a high-pressure gas tank (20) through a second pipeline (36) for storage; Step 3: Recycling self-pressurization intermittent precooling When the first temperature sensor (22) and the second temperature sensor (28) detect that the temperature of the filling box infusion pipeline (23) and the low-temperature filling box (27) has dropped to a preset value, the first liquid stop valve (5) and the second liquid stop valve (26) are kept in an open state, the second gas stop valve (21) is opened, the first gas stop valve (19), the third gas stop valve (30), the fourth gas stop valve (34) and the solenoid valve (14) are closed, and the high thermal conductivity porous medium booster (9) continues to operate to continue to transport the low-temperature liquid propellant in the liquid phase region (3) to the low-temperature filling box (27). At the same time, the high-pressure gas in the high-pressure gas tank (20) enters the gas phase region (2) through the second gas stop valve (21), supplements the self-pressurization of the low-temperature filling box (1), and increases the pre-cooling flow rate; When the precooling and filling time reaches the set value, the electric heater (10), the first liquid stop valve (5), the second liquid stop valve (26), the second gas stop valve (21), the first gas stop valve (19), the third gas stop valve (30), the fourth gas stop valve (34), the electromagnetic valve (14) and the compressor (16) are closed, and the cryogenic liquid propellant inside the cryogenic injection receiving tank (27) exchanges heat with the original propellant in the cryogenic injection receiving tank (27) and the wall surface of the cryogenic injection receiving tank (27); When the second pressure sensor (29) detects that the pressure in the cryogenic injection receiving tank (27) reaches a preset upper pressure limit, the compressor (16), the first gas stop valve (19), the third gas stop valve (30) and the fourth gas stop valve (34) are opened, and the cryogenic propellant vapor discharged from the cryogenic injection receiving tank (27) flows through the third gas stop valve (30), the injection receiving tank gas pipeline (31), the gas pipeline quick-connect interface (32), the injection tank gas pipeline (33) and the fourth gas stop valve (34) in sequence, enters the compressor (16) for compression, and then flows into the high-pressure gas tank (20) for storage through the second pipeline (36); When the second pressure sensor (29) detects that the pressure in the low-temperature injection receiving box (27) has dropped to a preset safety range, the compressor (16), the first gas stop valve (19), the third gas stop valve (30) and the fourth gas stop valve (34) are turned off, and the electric heater (10), the first liquid stop valve (5), the second liquid stop valve (26) and the second gas stop valve (21) are turned on to perform pre-cooling and filling again; this process is repeated to perform recovery-type self-pressurization intermittent pre-cooling; Step 4: Pump-driven non-vented filling When the first temperature sensor (22) detects that the temperature of the filling tank infusion pipeline (23) is precooled to the liquid temperature zone, and the second temperature sensor (28) detects that the temperature of the low-temperature receiving tank (27) reaches the precooling target temperature, the low-temperature liquid circulation pump (6), the first liquid stop valve (5), and the second liquid stop valve (26) are turned on, and the electric heater (10), the second gas stop valve (21), the first gas stop valve (19), the third gas stop valve (30), the fourth gas stop valve (34), the compressor (16), and the solenoid valve (14) are turned off. Under the driving action of the low-temperature liquid circulation pump (6), the low-temperature propellant is transferred from the low-temperature filling tank (1) to the low-temperature receiving tank (27). During the transfer process, the low-temperature receiving tank (27) is always not exhausted, thereby realizing the on-orbit lossless filling of the low-temperature propellant.

8. The method for in-orbit filling of cryogenic propellant according to claim 7, characterized in that: The step 1 also includes the cryogenic propellant vapor in the cryogenic filling tank (1) first entering the vapor cooling coil (15) through the fourth pipeline (38), then flowing out of the vapor cooling coil (15) and flowing into the compressor (16) through the fifth pipeline (39).

9. The method for in-orbit filling of cryogenic propellant according to claim 7, characterized in that: The step 2 also includes the step of allowing the cryogenic propellant vapor discharged from the cryogenic injection receiving tank (27) to first enter the vapor cooling coil (15) through the injection tank gas pipeline (33) and then flow into the compressor (16) through the fifth pipeline.

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