Electric propulsion low-temperature working medium on-orbit active refrigeration and pressure regulation coupling system and method

Abstract

The invention relates to an electric propulsion low-temperature working medium on-orbit active refrigeration and pressure regulation coupling system and method, and belongs to the technical field of spacecraft deep space exploration and on-orbit service. The cylinder structure is arranged in the storage box, flow guide plates are evenly arranged on the outer side of the cylinder structure, a plurality of open holes are machined in the cylinder structure, and the storage box and the heating evaporator are sequentially and circularly connected to form a pressurization loop; the storage box, the refrigerator, the pump and the cylinder structure are sequentially and circularly connected to form a refrigerating loop. Pressure and temperature control is achieved through self-circulation of the working medium, the state of the working medium can be adjusted, the portable working medium is added in a limited space, the space occupied by equipment such as an extra pressurization storage tank is greatly reduced, and the influence on spacecraft configuration design is reduced; according to the pressure self-adjusting technology designed according to the physical property of a working medium, a traditional high-pressure gas pressurization system is greatly simplified, space and weight resources of a spacecraft are greatly saved, and task feasibility is improved.

Description

TECHNICAL FIELD

[0001] The application relates to an active refrigeration and pressure regulation system and method, and belongs to the technical field of spacecraft deep space exploration and on-orbit service. BACKGROUND

[0002] As a new generation of propulsion technology, electric propulsion has gradually entered the engineering application stage in recent years, and the electric propulsion system of a satellite has been successfully applied on-orbit. Electric propulsion uses xenon, krypton, argon and other noble inert gases as working medium. Due to the high price of xenon, Internet constellation satellites, as a representative of electric propulsion models, also use krypton and argon as working medium. With the application of electric propulsion technology in spacecraft deep space exploration and on-orbit service, higher requirements are put forward for the carrying capacity and storage density of propellant working medium.

[0003] Taking xenon working medium as an example, due to its easy ionization, stable properties and large molecular weight, electric propulsion uses xenon as the main propellant working medium. For example, the patent with the publication number CN214663682U and the invention name of a xenon filling system for a satellite electric propulsion system discloses that the gas cylinder includes a gas source cylinder, an on-board cylinder and a xenon recovery cylinder which are respectively communicated with the system main pipe through valves; the xenon transfer device is divided into two layers, one of which is communicated with the system main pipe: the other is communicated with the low-temperature liquid nitrogen storage tank, and the heating displacement device is at least partially arranged outside the xenon transfer device; the patent with the publication number CN105858583A and the invention name of a space fuel storage tank fluid management system based on electric field effect discloses that a positive electrode rod is inserted into the center cylinder, and the gas bubbles finally break through the surface tension and fluid resistance of the small hole in the lower cylinder circumferential wall under the action of electric field force, and escape from the center cylinder to enter the inside of the fuel storage tank. A capillary screen is installed between the lower end of the center cylinder and the liquid discharge / filling port to block the gas bubbles and prevent the gas bubbles from being discharged with the liquid through the liquid discharge / filling port. The upper side of the storage tank is provided with an exhaust pipe. The above-mentioned electric propulsion working medium is basically stored in a gaseous state during on-orbit storage, and the storage density is low. The storage density of xenon working medium is generally only 1.6 kg / L. With the gradual popularization of deep space exploration missions and on-orbit filling service missions of electric propulsion working medium, spacecraft need to carry more propellants. For example, the Prometheus project carries about 1500 kg of xenon. If the supercritical state storage is still used, the volume and weight of the gas cylinder will increase significantly, and the existing technology uses additional working medium input, which further increases the occupied space and directly affects the configuration design of the spacecraft. The existing spacecraft propulsion system storage tank is pressurized, and a high-pressure pressure regulation system is used. The system is too complex and occupies too many resources of the spacecraft.

[0004] The common low-temperature working fluid active refrigeration system includes: (1) a thermodynamic vent system (TVS): based on an open-loop refrigeration technology, a device for utilizing the pressure difference between the inside and outside of a low-temperature tank for throttling and heat exchange with the propellant inside the tank, mainly composed of a Joule-Thomson expansion valve, a heat exchanger and a control valve; the system extracts two-phase flow from the inside of the tank, flows through the Joule-Thomson valve for thermodynamic expansion; the two-phase flow is reduced in temperature after passing through the Joule-Thomson valve, and exchanges heat with the remaining fluid or wall surface in the tank, and is finally completely vaporized and discharged from the system, achieving the purpose of reducing the temperature of the fluid in the tank; through this process, the heat in the tank is removed, achieving the refrigeration effect, thereby reducing the pressure of the tank; (2) liquid mixing technology (LMT): refers to using a liquid mixing device to eliminate the thermal stratification phenomenon of the propellant inside the propellant tank, thereby reducing the pressure inside the tank and reducing the evaporation of the low-temperature propellant, aiming to fully mix the low-temperature fluid cooled by the active refrigeration system and the hot fluid in the tank by physical methods to reduce the overall temperature; its main feature is that through the refrigeration machine, pump and jet rod, the temperature homogenization and physical cooling of the tank can be effectively realized. The above-mentioned active refrigeration methods are mainly aimed at the use requirements of launch vehicles, which have low sensitivity to long life and space microgravity environment. However, for spacecraft, space resources and weight resources are very valuable, and the thermodynamic vent system inevitably causes loss of low-temperature propellant by vaporizing and discharging the propellant used for refrigeration from the system, which is unacceptable for long-term tasks of spacecraft; similarly, for the liquid mixing technology, the installation of the jet rod in the tank increases the weight of the system, and more importantly, the presence of the jet rod destroys the management ability of the PMD of the tank for the liquid propellant in the microgravity environment, reduces the extrusion efficiency of the tank, and makes more liquid propellant unable to be discharged from the tank, becoming the dead weight of the system.

[0005] For the field of space propulsion, a high-pressure system is usually designed to store pressurized gas in advance; in the working process of the tank, the pressurized gas is supplied to the downstream tank through valves, pressure reducers and the like to maintain a certain pressure; for example, a spacecraft dual-component propulsion system generally carries 35 MPa high-pressure helium stored in a helium cylinder; during the orbit transfer process of a 490 N engine, the high-pressure helium is supplied to the downstream tank to maintain a constant pressure. The problem of the above-mentioned pressure regulating system is that the system is complex, and its weight accounts for about 25% of the entire propulsion system, and after the high-pressure helium is consumed, the pressure regulating system will become the dead weight of the system, greatly occupying the space and weight resources of the spacecraft.

[0006] Therefore, it is urgent to propose an electric propulsion low-temperature working fluid on-orbit active refrigeration and pressure regulation coupling system and method to solve the above technical problems. SUMMARY

[0007] To solve the complex problem of propulsion system, an active refrigeration device for electric propulsion working medium combined with tank PMD is provided. A brief summary of the present application is given below to provide a basic understanding of some aspects of the present application. It should be understood that this summary is not an exhaustive summary of the present application. It is not intended to determine the key or important parts of the present application, nor to limit the scope of the present application.

[0008] Technical scheme of the present application: An active refrigeration device for electric propulsion working medium, comprising: a jet pipe arranged in a tank, a plurality of flow guide plates arranged uniformly outside the jet pipe, a plurality of openings arranged on the jet pipe, and further comprising: The tank, the heating evaporator and the pump are sequentially connected to form a pressurization circuit. The tank, the refrigeration machine and the pump are sequentially connected to form a refrigeration circuit.

[0009] Preferably, the tank inlet is located on the upper side or the side, and the lower side of the tank has an opening.

[0010] Preferably, the jet pipe is located at the center, the jet pipe is a cylindrical type with an inner cavity, the inner cavity of the jet pipe is communicated with the inner cavity of the tank through a plurality of openings arranged circumferentially, and the lower end of the jet pipe is connected with the pump outside the tank through a first conduit.

[0011] Preferably, a liquid accumulator is arranged at the opening of the lower side of the tank, the upper side and / or the side of the liquid accumulator has a plurality of inlets, and the liquid accumulator is communicated with the inner cavity of the tank through the inlets.

[0012] Preferably, a plurality of flow guide plates are arranged circumferentially and uniformly outside the jet pipe, and a plurality of radial jet openings arranged along the axial direction are arranged on the side wall of the jet pipe between adjacent flow guide plates.

[0013] Preferably, the outlet of the liquid accumulator is connected with the first port of a four-way pipe, the second port of the four-way pipe is connected with the refrigeration machine for supplying working medium to the refrigeration circuit, the third port of the four-way pipe is connected with the heating evaporator for supplying working medium to the pressurization circuit, and the fourth port of the four-way pipe is used for supplying working medium.

[0014] Preferably, a third electromagnetic valve is arranged on the second conduit between the heating evaporator and the tank inlet.

[0015] Preferably, the tank is provided with a first pressure sensor and a first temperature sensor.

[0016] Preferably, the opening at the lower end of the tank, the inlet at the upper end of the tank and the jet pipe are coaxially arranged at the center, the upper outer end of the flow guide plate group formed by the circumferential array of a plurality of flow guide plates has a protrusion, and the center of the flow guide plate group forms a recess.

[0017] An active refrigeration method of an electric propulsion working medium, adopting an active refrigeration device of an electric propulsion working medium, comprising the following steps: The storage tank has the working medium; when the temperature is too high and / or the pressure is too high, the refrigeration circuit is started, and the liquid working medium of the storage tank is sprayed into the storage tank through the cooling delivery; when the pressure and / or the temperature are too low, the pressure increasing circuit is started, and the liquid working medium of the storage tank is gasified and delivered into the storage tank.

[0018] The present application has the following beneficial effects: The present application has the following beneficial effects:

[0019] The present application increases the contact area and improves the heat exchange efficiency.

[0020] The present application realizes pressure and temperature control through self-circulation of the working medium, and the state of the working medium can be adjusted, which not only increases the carrying capacity of the working medium in a limited space, but also greatly reduces the space occupied by additional pressure increasing tanks and other equipment, and reduces the influence on the spacecraft configuration design. The pressure self-adjusting technology designed according to the working medium properties greatly simplifies the traditional high-pressure gas pressure increasing system, greatly saves the spacecraft space and weight resources, and improves the mission feasibility. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of an active refrigeration device of an electric propulsion working medium. Figure 2 It is a partial view of an active refrigeration device of an electric propulsion working medium. Figure 3 It is a PρT relationship diagram of xenon. Figure 4 It is an application schematic diagram of an active refrigeration device of an electric propulsion working medium. Figure 5 It is a flow chart of an active refrigeration device of an electric propulsion working medium.

[0022] In the figure, 1 is a storage tank, 2 is a jet pipe, 3 is a first conduit, 4 is a refrigerator, 5 is a first electromagnetic valve, 6 is a first safety valve, 7 is a gasifier, 8 is a second electromagnetic valve, 9 is a second safety valve, 10 is a buffer tank, 11 is a second temperature sensor, 12 is a second pressure sensor, 13 is a third flange, 14 is a first flange, 15 is a second flange, 16 is a heat insulation layer, 17 is a satellite structure, 18 is a pump, 19 is a heating evaporator, 20 is a four-way pipe, 21 is a second conduit, 22 is a third electromagnetic valve, 23 is a working medium outlet hole, 24 is a flow guide plate, 25 is an accumulator, 26 is a first pressure sensor, and 27 is a first temperature sensor. DETAILED DESCRIPTION

[0023] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be described below in detail with specific embodiments shown in the drawings. However, it should be understood that the description is only exemplary and is not intended to limit the scope of the present application. In addition, in the following description, the description of the known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present application.

[0024] Specific implementation method one: combination Figures 1-2 In this embodiment, the opening section of the injection pipe 2 is arranged in the storage tank 1, the outer side of the injection pipe 2 is provided with the flow guide plates 24 arranged uniformly in the circumferential direction, the injection pipe 2 is processed with a plurality of openings 23, the storage tank 1 stores the working medium, the storage tank contains the propellant management device (PMD), which can realize effective management of the propellant under microgravity, and ensure that the working medium discharged from the storage tank is liquid working medium; wherein the PMD is composed of the injection pipe (central cylinder) and the flow guide plates, the central cylinder plays a structural support role, and the central cylinder is uniformly provided with injection holes, under the action of the refrigerator and the pump, the working medium after refrigeration is injected to each part of the storage tank; The device comprises: The storage tank 1 and the heating evaporator 19 are sequentially and circularly connected to form a pressurization circuit; the working medium in the storage tank 1 is heated and gasified by the heating evaporator 19 and then returned to the storage tank 1 for pressure adjustment; by using the characteristics of low boiling point and easy gasification of the commonly used working medium for electric propulsion such as xenon (boiling point -108.1℃), krypton (boiling point -153.35℃), and argon (boiling point -185.3℃), a pressure self-adjusting system is designed to adjust the working pressure of the storage tank and meet the working medium supply requirements, that is, by using the physical characteristics of low boiling point of xenon, krypton, and argon, and combining the gasifier, the liquid working medium flowing out is gasified and then flows into the storage tank, realizing self-adjustment of the pressure of the storage tank and further simplifying the complexity of the system; The storage tank 1, the refrigerator 4, the pump 18, and the injection pipe 2 are sequentially and circularly connected to form a refrigeration circuit; the storage tank 1 is a surface tension storage tank for storing the working medium, the pump 18 is a liquid pump, the working medium in the storage tank 1 is cooled by the refrigerator 4 and uniformly sprayed into the storage tank 1 through the injection pipe 2, and the injection pipe 2 is used to reduce the temperature of the working medium in the storage tank 1; The present invention is based on the physical properties of electric propulsion fluids such as xenon, krypton, and argon, and according to the change of working fluid density with temperature, designs a scheme to achieve high-density storage of working fluids through on-orbit low-temperature storage, which effectively increases the on-orbit working fluid carrying capacity. At the same time, the working fluid in the tank 1 itself is used to enter the boosting circuit and the refrigeration circuit, and the pressure and temperature are controlled by the self-circulation of the working fluid. The working fluid state is adjustable, which not only increases the portable working fluid in a limited space, but also greatly reduces the space occupied by additional storage tanks and other equipment, reduces the impact on the spacecraft configuration design, and realizes the controllable adjustment of the state of the working fluid storage and transportation process. The pressure self-regulation technology designed by the present invention based on the physical properties of the working fluid greatly simplifies the traditional high-pressure gas boosting system, greatly saves space and weight resources of the spacecraft, and improves the feasibility of the mission.

[0025] Specific implementation method 2: Combination Figures 1-2 This embodiment describes an active refrigeration device for an electric propulsion working fluid. The inlet of the tank 1 is located on the upper side or side as a gas working fluid pressurization inlet, and the lower side of the tank 1 has an opening. The structure of the present invention is simple, low-cost, and not easy to damage. It can achieve high-density storage and efficient supply of working fluids such as xenon, krypton, and argon for electric propulsion, effectively supporting the promotion and application of electric propulsion in deep space exploration, on-orbit services and other fields.

[0026] Specific implementation method three: Combination Figures 1-2 The present embodiment is described. This embodiment is an active refrigeration device for an electric propulsion working fluid. The injection pipe 2 is located at the axial center position in the tank 1. The injection pipe 2 is cylindrical with an inner cavity. The inner cavity of the injection pipe 2 is connected to the inner cavity of the tank 1 through a plurality of circumferential openings 23. The lower end of the injection pipe 2 is connected to the pump 18 outside the tank 1 through a first conduit 3. The upper end of the injection pipe 2 is sealed. The hydraulic pressure is concentrated at the opening 23. The working fluid is injected over a long distance, which further improves the cooling range and achieves uniform and efficient cooling.

[0027] Specific implementation method four: Combination Figures 1-2 To describe this embodiment, an active refrigeration device for an electric propulsion working medium is provided with a liquid accumulator 25 at the lower opening of the storage tank 1. The upper side and / or side of the liquid accumulator 25 have a plurality of inlets, and a screen is provided at the inlet. The liquid accumulator 25 is connected to the inner cavity of the storage tank 1 through the inlet. The working medium in the storage tank 1 flows from the inlet of the liquid accumulator 25 to the boost circuit and the refrigeration circuit.

[0028] Specific implementation method five: Combination Figures 1-2The embodiment is explained, and the active refrigeration device of the electric propulsion working medium of the embodiment is provided with an opening 23 on the injection pipe 2, and the injection pipe 2 is provided with circumferentially uniformly arranged flow guide plates 24 outside, the side wall of the injection pipe 2 between adjacent flow guide plates 24 is provided with a plurality of openings 23 in the axial direction, the active refrigeration system is combined with the PMD structure of the storage tank, the system complexity is reduced, the key problem of the influence of the injection rod on the space fluid management is solved, the pressure self-regulation technology of the electric propulsion working medium is used, a large amount of space and weight resources of the spacecraft are saved, the above technical method is the first creation in the field of spacecraft propulsion technology, and has great originality; the liquid working medium flowing out of the storage tank is cooled by the refrigerator, the working medium is delivered back to the storage tank by the cryogenic pump, and is sprayed out through the openings of the outer wall of the ring cavity, so that the function of uniform stirring of the working medium is realized; the electric propulsion working medium is stored and managed in orbit at high density, the refrigeration system (active and passive heat protection technology) is reasonably designed, the working medium is maintained in a low-temperature liquid state during storage, the temperature is uniform, and finally the working medium is "zero evaporation", so that the long service life of 15 years in orbit is met.

[0029] Specific implementation method six: in combination Figures 1-2 The embodiment is explained, and the active refrigeration device of the electric propulsion working medium of the embodiment is provided with an opening 23 on the injection pipe 2, and the injection pipe 2 is provided with circumferentially uniformly arranged flow guide plates 24 outside, the side wall of the injection pipe 2 between adjacent flow guide plates 24 is provided with a plurality of openings 23 in the axial direction, the active refrigeration system is combined with the PMD structure of the storage tank, the system complexity is reduced, the key problem of the influence of the injection rod on the space fluid management is solved, the pressure self-regulation technology of the electric propulsion working medium is used, a large amount of space and weight resources of the spacecraft are saved, the above technical method is the first creation in the field of spacecraft propulsion technology, and has great originality; the liquid working medium flowing out of the storage tank is cooled by the refrigerator, the working medium is delivered back to the storage tank by the cryogenic pump, and is sprayed out through the openings of the outer wall of the ring cavity, so that the function of uniform stirring of the working medium is realized; the electric propulsion working medium is stored and managed in orbit at high density, the refrigeration system (active and passive heat protection technology) is reasonably designed, the working medium is maintained in a low-temperature liquid state during storage, the temperature is uniform, and finally the working medium is "zero evaporation", so that the long service life of 15 years in orbit is met.

[0030] Specific implementation method seven: in combination Figures 1-2 The embodiment is explained, and the active refrigeration device of the electric propulsion working medium of the embodiment is provided with an opening 23 on the injection pipe 2, and the injection pipe 2 is provided with circumferentially uniformly arranged flow guide plates 24 outside, the side wall of the injection pipe 2 between adjacent flow guide plates 24 is provided with a plurality of openings 23 in the axial direction, the active refrigeration system is combined with the PMD structure of the storage tank, the system complexity is reduced, the key problem of the influence of the injection rod on the space fluid management is solved, the pressure self-regulation technology of the electric propulsion working medium is used, a large amount of space and weight resources of the spacecraft are saved, the above technical method is the first creation in the field of spacecraft propulsion technology, and has great originality; the liquid working medium flowing out of the storage tank is cooled by the refrigerator, the working medium is delivered back to the storage tank by the cryogenic pump, and is sprayed out through the openings of the outer wall of the ring cavity, so that the function of uniform stirring of the working medium is realized; the electric propulsion working medium is stored and managed in orbit at high density, the refrigeration system (active and passive heat protection technology) is reasonably designed, the working medium is maintained in a low-temperature liquid state during storage, the temperature is uniform, and finally the working medium is "zero evaporation", so that the long service life of 15 years in orbit is met.

[0031] Specific implementation method eight: in combination Figures 1-2 The embodiment is explained, and the active refrigeration device of the electric propulsion working medium of the embodiment is provided with an opening 23 on the injection pipe 2, and the injection pipe 2 is provided with circumferentially uniformly arranged flow guide plates 24 outside, the side wall of the injection pipe 2 between adjacent flow guide plates 24 is provided with a plurality of openings 23 in the axial direction, the active refrigeration system is combined with the PMD structure of the storage tank, the system complexity is reduced, the key problem of the influence of the injection rod on the space fluid management is solved, the pressure self-regulation technology of the electric propulsion working medium is used, a large amount of space and weight resources of the spacecraft are saved, the above technical method is the first creation in the field of spacecraft propulsion technology, and has great originality; the liquid working medium flowing out of the storage tank is cooled by the refrigerator, the working medium is delivered back to the storage tank by the cryogenic pump, and is sprayed out through the openings of the outer wall of the ring cavity, so that the function of uniform stirring of the working medium is realized; the electric propulsion working medium is stored and managed in orbit at high density, the refrigeration system (active and passive heat protection technology) is reasonably designed, the working medium is maintained in a low-temperature liquid state during storage, the temperature is uniform, and finally the working medium is "zero evaporation", so that the long service life of 15 years in orbit is met.

[0032] Specific implementation method nine: in combination Figures 1-2The embodiment is described, and the electric propulsion working medium active refrigeration device of the embodiment is coaxially arranged at the center of the opening at the lower end of the tank 1, the inlet at the upper end of the tank 1 and the injection pipe 2. The outer end of the upper side of the guide plate group formed by the circumferential array of the guide plates 24 has a protrusion, so that the center of the guide plate group forms a recess, thereby facilitating fluid guidance.

[0033] Specific implementation ten: Figures 1-5 The embodiment is described, and the electric propulsion working medium active refrigeration device of the embodiment is coaxially arranged at the center of the opening at the lower end of the tank 1, the inlet at the upper end of the tank 1 and the injection pipe 2. The outer end of the upper side of the guide plate group formed by the circumferential array of the guide plates 24 has a protrusion, so that the center of the guide plate group forms a recess, thereby facilitating fluid guidance. The structure upstream of the gasifier is used to achieve the following: The tank 1 contains a working medium, which can be xenon, krypton or argon. The pressure and temperature in the tank 1 are detected by the first pressure sensor 26 and the first temperature sensor 27. If there is temperature stratification and / or pressure instability, that is, the temperature and pressure do not meet the set value. When the temperature does not meet the set value or the pressure is too high (higher than the set range), the refrigerator 4 and the pump 18 of the refrigeration circuit are started, and the remaining paths are closed. The liquid working medium of the tank 1 is cooled and delivered to the injection pipe 2, and is uniformly sprayed into the tank 1 through the working medium outlet hole 23 of the injection pipe 2. When the pressure is too low (lower than the set range), the third electromagnetic valve 22 and the heating evaporator 19 of the pressurization circuit are started, and the remaining paths are closed. The liquid working medium of the tank 1 is gasified and delivered to the tank 1 through the heating evaporator 19. The application is applied to an electric propulsion working medium on-orbit high-density storage and management system. Based on the physical properties of xenon, krypton, argon and other electric propulsion working media, the temperature of the on-orbit working medium storage cylinder is controlled to convert the supercritical state working medium into a liquid state or a gas-liquid mixed state or even a solid state, thereby improving the storage density of the working medium, effectively increasing the carrying capacity of the electric propulsion working medium, and also effectively reducing the system working pressure, simplifying the complexity of the propulsion system and reducing the potential failure risk. It can be applied to spacecraft thermal control, liquid propellant microgravity management and liquid propellant gasification and evaporation use, and provides important support for deep space exploration, on-orbit service and other tasks.

[0034] Example 1: The application is combined Figures 1-5 As shown in the figure: An electric propulsion working medium active refrigeration device is applied to an electric propulsion working medium on-orbit high-density storage and supply device, which is suitable for active refrigeration of liquid hydrogen and liquid oxygen low-temperature propellants of launch vehicles. There is a need to consume a certain amount of propellant, and the internal installation of the injection rod of the tank destroys the microgravity environment for fluid management. The active refrigeration technology designed in the application improves the existing tank PMD structure without affecting the propellant management capability of the tank in the on-orbit microgravity environment. It includes: Refrigeration circuit: The tank 1, the refrigerator 4, the pump 18 and the injection pipe 2 are sequentially and circularly connected to form a refrigeration circuit. The refrigeration circuit further comprises a first conduit 3, and an output end of a pump 18 arranged outside the storage tank 1 is connected with an input end of the injection pipe 2 arranged inside the storage tank 1 through the first conduit 3; the application increases the portable working medium in the limited space, and reduces the influence on the configuration design of the spacecraft; The injection pipe 2 is arranged at the axis of the storage tank 1, and a plurality of medium outlet holes evenly arranged are machined on the injection pipe 2 as output ends of the injection pipe 2; The pressurization circuit: the storage tank 1 and the heating evaporator 19 are circularly connected to form the pressurization circuit; The pressurization circuit further comprises a second conduit 21, and an output end of the heating evaporator 19 is connected with an input end of the storage tank 1 through the second conduit 21; the liquid working medium is heated and vaporized through the heating evaporator, and is filled into the storage tank to realize self-regulation of the pressure of the storage tank; The gaseous working medium circuit: the storage tank 1, the vaporizer 7 and the buffer tank 10 are sequentially connected to form the gaseous working medium circuit; the vaporizer 7 is used for vaporizing the working medium; the working medium in the storage tank 1 is heated and vaporized into the vaporizer 7, the vaporizer 7 adopts the heating evaporator, and high-pressure working medium is formed in the buffer tank 10; The four-way pipe 20 is further included, one pipe opening of the four-way pipe 20 is connected with the output end of the storage tank 1, and the other three pipe openings of the four-way pipe 20 are respectively connected with the input ends of the refrigerator 4, the heating evaporator 19 and the vaporizer 7; The gaseous working medium circuit further comprises a first electromagnetic valve 5 and a first safety valve 6, the storage tank 1 is connected with the input end of the first electromagnetic valve 5 through the opening corresponding to the vaporizer of the four-way pipe 20, the output end of the first electromagnetic valve 5 is connected with the input end of the vaporizer 7, and the first safety valve 6 is arranged on the pipeline between the input end of the first electromagnetic valve 5 and the pipe opening corresponding to the vaporizer of the four-way pipe 20; The gaseous working medium circuit further comprises a second electromagnetic valve 8, a second safety valve 9, a second temperature sensor 11 and a second pressure sensor 12, the second electromagnetic valve 8 and the second safety valve 9 are connected with the input end of the buffer tank 10, and the second temperature sensor 11 and the second pressure sensor 12 are connected with the output end of the buffer tank 10; the working medium flowing into the buffer tank after being vaporized is controlled in the required pressure range through the control of the opening and closing time of the valve and the temperature and pressure control measures, so as to facilitate the pressure and flow management of the downstream; Based on the physical characteristics of the gaseous working medium: All substances may present solid state, liquid state, gas-liquid mixed state, gaseous state and supercritical state and the like under different pressure P and temperature T combinations, and the corresponding density is a certain value; Taking xenon as an example, the relationship between the phase transition density and the pressure P and the temperature T is as shown in the figure; Figure 3 As shown in the figure, when the temperature is higher than 16.6℃, the xenon is in the gaseous state, and if the pressure is higher than 5.84MPa at the same time, the xenon is in the supercritical state; under the supercritical state, the density of the xenon behaves like the liquid state, but the transport characteristics behave like the gaseous state; The physical properties of xenon, krypton and argon are shown in Table 1; similar to the physical properties of xenon, only when the storage temperature is lower than the critical temperature, liquid or solid working medium will appear; therefore, in order to realize high-density storage of the working medium, the storage temperature needs to be first reduced to be lower than the supercritical temperature of the working medium; Table 1 Physical properties of xenon, krypton and argon working medium

[0035] On this basis, according to the carrying amount of the on-orbit spacecraft electric propulsion working medium, the structural envelope requirement of the spacecraft itself, the on-orbit refrigeration capacity and other factors, the appropriate low-temperature storage temperature is selected according to the physical properties of xenon, krypton and argon and other working media, so as to realize high-density storage of the working medium; The corresponding relationship between the saturation vapor pressure, liquid density and gas density of xenon, krypton and argon at different temperatures is shown in Table 2; as the temperature decreases, the saturation vapor pressure of the working medium will decrease, and the liquid density will increase, which means that more electric propulsion working medium can be stored; Table 2 Density of working medium at different temperatures

[0036] The on-orbit management and supply system of the low-temperature working medium mainly comprises a surface tension tank, a thermal control system (a refrigerator 4 and a jet pipe 2), a valve, a buffer gas container (a buffer tank 10), a heating evaporator (a gasifier 7) and a temperature and pressure sensor, wherein the tank 1 needs to be adiabatic, and is used for isolating heat conduction between the inside and outside of the tank 1; the opening and closing time of the valve is controlled, so that the mass of the liquid propellant flowing into the buffer gas bottle is controlled, and the liquid supply gas is heated and evaporated by the heating evaporator; and finally, gaseous working medium is provided for the downstream storage and supply system; The number of the buffer tank 10 is one or two, and the output end of the gasifier 7 is connected with the input ends of the two second electromagnetic valves 8 in parallel; the control is facilitated, and the flow delivery is stable; The structure of the application is simple, low in cost and not easy to be damaged, can realize high-density storage and efficient supply of electric propulsion xenon, krypton, argon and other working media, and realizes the on-orbit "zero evaporation" electric propulsion working medium low-temperature high-density tank and management system; effectively supports the popularization and application of electric propulsion in deep space exploration and on-orbit service fields; The gaseous working medium path further comprises a third flange 13 and a first flange 14, the first electromagnetic valve 5 and the first safety valve 6 are connected with the corresponding openings of the gasifier of the four-way pipe 20 through the first flange 14, and the second safety valve 9 and the buffer tank 10 are connected with the second electromagnetic valve 8 through the third flange 13; the output end of the application is an outlet, and the input end is an inlet; The second flange 15 and the heat insulation layer 16 are further included, the outer side of the storage tank 1 is wrapped with the heat insulation layer 16, and the storage tank 1 is detachably connected with the satellite structure 17 through the second flanges 15 arranged on the upper and lower sides, the application is heat-insulated for the storage tank, and heat conduction between the inside and the outside of the storage tank is insulated; the application increases the carryable working medium in the limited space, and reduces the influence on the spacecraft configuration design; The working medium storage is achieved through the upstream structure of the gasifier: the working medium in the storage tank 1 can be xenon, krypton or argon, the pressure and temperature in the storage tank 1 are detected through the first pressure sensor 26 and the first temperature sensor 27, if there is temperature stratification and / or pressure instability, that is, the temperature and pressure do not meet the set value; when the temperature does not meet the set value or the pressure is too high (higher than the set range), the refrigerator 4 and the pump 18 of the refrigeration circuit are started, the remaining passages are closed, the liquid working medium of the storage tank 1 is delivered to the injection pipe 2 through cooling, and is uniformly sprayed into the storage tank 1 through the working medium outlet hole 23 of the injection pipe 2; when the pressure is too low (lower than the set range), the third electromagnetic valve 22 and the heating evaporator 19 of the pressurization circuit are started, the remaining passages are closed, and the liquid working medium of the storage tank 1 is delivered to the storage tank 1 through the heating evaporator 19; The working medium delivery is achieved through the end downstream of the gasifier connected with the electric thruster through a pneumatic or electromagnetic valve, and is used for delivering the gaseous working medium to the electric thruster: the working medium in the storage tank 1 can be xenon, krypton or argon, the pressure and temperature in the storage tank 1 are detected through the first pressure sensor 26 and the first temperature sensor 27, if the requirements of the working medium storage are not met, the adjustment of the working medium storage step is performed to make it meet the set value, and the working medium is delivered downstream of the evaporator; when the gaseous working medium is delivered downstream of the evaporator, the refrigeration circuit and the pressurization circuit are closed, the second electromagnetic valve 8 is started, and then the first electromagnetic valve 5 is started, the pressure of the buffer tank 10 is detected through the second pressure sensor 12 until the set value is met, the second electromagnetic valve 8 and the first electromagnetic valve 5 are closed, and if the set value is not met, the second electromagnetic valve 8 and the first electromagnetic valve 5 are started again; the buffer tank 10 is detected through the second temperature sensor 11, if it is low, the heating device can be started until the set value is met, when the pressure is less than the set value during the supply through the opening of the end valve, the end valve is closed to stop the gas supply, and the second electromagnetic valve 8 and the first electromagnetic valve 5 are started again; the on-orbit high-density storage and management of the electric propulsion working medium are realized; Work flow: The liquid xenon working medium is stored, and the storage and supply process of the liquid xenon is as follows: Step one: the propellant working medium is stored in the storage tank 1 in the form of liquid, the storage tank 1 is actively temperature-controlled at-25℃ to-20℃, and the pressure is about 2 to 3 MPa; Step two: the first electromagnetic valve 5 is opened, the liquid xenon pushes the propellant working medium into the downstream pipeline through the action of surface tension and pressure difference, and is gasified by the gasifier 7, a small amount of xenon gas enters the low-temperature buffer tank 10 in the moment of the short opening of the first electromagnetic valve 5; Step three: after a certain amount of xenon gas flows into the buffer tank 10, heat it to 16.6°C or higher to make it completely gasified, forming high-pressure xenon gas (about 3-5 MPa) into the downstream pressure control module; The branches of the two groups of buffer tanks 10 are connected in parallel, the purpose is to flow into-gasify xenon alternately with the branch, so that the downstream flow is as stable as possible; Step four: the buffer tank 10 is supplied, when the pressure in any buffer tank 10 is less than a certain value, go to step two.

[0037] It should be noted that in the above embodiments, as long as the technical solutions are not contradictory, they can be arranged and combined. Those skilled in the art can exhaust all possibilities according to the mathematical knowledge of arrangement and combination, so the invention will not be repeated one by one. However, it should be understood that the technical solutions after arrangement and combination have been disclosed by the invention.

[0038] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Those skilled in the art can make various changes and modifications to the present application. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. Electric propulsion cryogenic fluid on-orbit active refrigeration and pressure regulation coupling system, including: The injection pipe (2) is arranged in the storage tank (1), and the outer side of the injection pipe (2) is provided with uniformly arranged guide plates (24). The injection pipe (2) is densely covered with openings (23). The invention is characterized in that it further comprises: The storage tank (1) and the heating evaporator (19) are connected in a circular manner to form a boosting circuit; The storage tank (1), the refrigerator (4), the pump (18), and the injection pipe (2) are connected in sequence to form a refrigeration circuit.

2. The electric propulsion cryogenic fluid on-orbit active refrigeration and pressure regulation coupling system according to claim 1 is characterized in that: The inlet of the tank (1) is located on the upper side or the side, and the lower side of the tank (1) has an opening.

3. The electric propulsion cryogenic fluid on-orbit active refrigeration and pressure regulation coupling system according to claim 2 is characterized in that: The injection pipe (2) is located at the center. The injection pipe (2) is cylindrical with an inner cavity. The inner cavity of the injection pipe (2) is connected to the inner cavity of the storage tank (1) through a plurality of circumferential openings (23). The lower end of the injection pipe (2) is connected to the pump (18) outside the storage tank (1) through a first conduit (3).

4. The electric propulsion cryogenic fluid on-orbit active refrigeration and pressure regulation coupling system according to claim 3 is characterized by: A liquid accumulator (25) is provided at the lower opening of the storage tank (1). The upper side and / or side of the liquid accumulator (25) are provided with a plurality of inlets, and the liquid accumulator (25) is communicated with the inner cavity of the storage tank (1) through the inlets.

5. The electric propulsion cryogenic fluid on-orbit active refrigeration and pressure regulation coupling system according to claim 3 or 4, characterized in that: Guide plates (24) are arranged evenly in the circumferential direction on the outside of the injection pipe (2), and a plurality of openings (23) are provided on the side wall of the injection pipe (2) between adjacent guide plates (24) along the axial direction.

6. The electric propulsion cryogenic fluid on-orbit active refrigeration and pressure regulation coupling system according to claim 3 is characterized by: The outlet of the accumulator (25) is connected to the first pipe opening of the four-way pipe (20), the second pipe opening of the four-way pipe (20) is connected to the refrigerator (4) for supplying a working medium to the refrigeration circuit, the third pipe opening of the four-way pipe (20) is connected to the heating evaporator (19) for supplying a working medium to the boosting circuit, and the fourth pipe opening of the four-way pipe (20) is used to supply a working medium.

7. The electric propulsion cryogenic fluid on-orbit active refrigeration and pressure regulation coupling system according to claim 6 is characterized in that: A third solenoid valve (22) is provided on the second conduit (21) between the heating evaporator (19) and the inlet of the storage tank (1).

8. The electric propulsion cryogenic fluid on-orbit active refrigeration and pressure regulation coupling system according to claim 1, 2, 3 or 6, characterized in that: The storage tank (1) is provided with a first pressure sensor (26) and a first temperature sensor (27).

9. The electric propulsion cryogenic fluid on-orbit active refrigeration and pressure regulation coupling system according to claim 8, characterized in that: The opening at the lower end of the tank (1), the inlet at the upper end of the tank (1), and the injection pipe (2) are all coaxially arranged at the center. The upper outer end of the guide plate group formed by a circumferential array of a plurality of guide plates (24) has a protrusion, so that the center of the guide plate group forms a depression.

10. An on-orbit active cooling and pressure regulation method for a cryogenic working fluid in electric propulsion, characterized by: The electric propulsion cryogenic fluid on-orbit active refrigeration and pressure regulation coupling system according to any one of claims 1 to 9 comprises the following steps: The storage tank (1) contains a working medium; when the temperature and / or pressure are too high, the refrigeration circuit is activated, and the liquid working medium in the storage tank (1) is cooled and transported to be sprayed into the storage tank (1); when the pressure and / or temperature are too low, the boosting circuit is activated, and the liquid working medium in the storage tank (1) is vaporized and transported to the storage tank (1).

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