Space propulsion system and its propulsion method

Abstract

The present invention provides a space propulsion system and a propulsion method thereof. The space propulsion system serves as a propulsion system for a very low orbit satellite or a planetary probe with an atmosphere. The space propulsion system includes an air intake device, a gas supply pipeline, and a nanowire array ion thruster, wherein: the air intake device collects the gas in the orbit as a propellant; the gas is supplied to the nanowire array ion thruster by the gas supply pipeline, ionized by the strong electric field of the nanowire array ion thruster, and accelerated and ejected by the strong electric field to generate thrust; the material of the nanowire array ion thruster is an oxide.

Description

Technical Field

[0001] The present invention relates to the technical field of electric propulsion, and particularly relates to a space propulsion system and a propulsion method thereof. Background Art

[0002] Due to the advantages of high specific impulse, light weight, simple structure, etc., electric propulsion technology is increasingly applied to the orbit keeping and attitude control of satellites, and has begun to be used as the main propulsion of deep space probes to perform orbit maintenance and orbit transfer tasks. However, since only a certain amount of propellant can be carried during the ground launch of a satellite, the lifespan of the satellite is usually limited by the lifespan of the propulsion system. Summary of the Invention

[0003] The purpose of the present invention is to provide a space propulsion system and a propulsion method thereof to solve the problem that the limited weight of the propellant carried by the existing thruster affects its service life.

[0004] To solve the above technical problems, the present invention provides a space propulsion system. The space propulsion system is used as the propulsion system of an ultra-low orbit satellite or a planetary probe with an atmosphere. The space propulsion system includes an air intake device, an air supply pipeline, and a nanowire array ion thruster, wherein:

[0005] The air intake device collects the gas in the orbit as the propellant;

[0006] The gas is provided to the nanowire array ion thruster by the air supply pipeline, ionized by the strong electric field of the nanowire array ion thruster, and accelerated and ejected by the strong electric field to generate thrust;

[0007] The material of the nanowire array ion thruster is an oxide.

[0008] Optionally, in the space propulsion system, the nanowire array ion thruster includes a grid retaining ring, a grid, an insulating support, a nanowire array assembly, and a base that are sequentially connected and matched from top to bottom, wherein:

[0009] The grid retaining ring is an annular part made of an insulating material;

[0010] The insulating support is in a ring structure and is used for electrical insulation between the grid and the nanowire array assembly;

[0011] The nanowire array assembly is placed on the base, the insulating support clamps the nanowire array assembly tightly, the grid is placed on the upper edge of the insulating support, the grid retaining ring is fixed to the edge of the grid, and the grid is stuck in the grid retaining ring and pressed tightly by the grid retaining ring.

[0012] Optionally, in the space propulsion system, the nanowire array assembly is an integrated configuration composed of a substrate, a nanowire array, and a flow channel;

[0013] The substrate is a circular thin sheet made of silicon, ceramic, or stainless steel;

[0014] The bottom surface of the substrate is parallel to the gate and the base;

[0015] The nanowire array grows from the substrate and includes, but is not limited to, zinc oxide nanowires, tungsten oxide nanowires, copper oxide nanowires, or titanium dioxide nanowires;

[0016] The flow channel is a uniformly distributed hole penetrating the height direction of the substrate;

[0017] The hole diameter of the flow channel is 10 microns to 100 microns.

[0018] Optionally, in the space propulsion system, the material of the gate is tungsten, molybdenum, or carbon, the shape of the gate is a circular thin sheet structure, the gate is provided with gate holes penetrating the height direction of the gate, the gate holes serve as channels for ion acceleration and ejection, and the hole diameter of the gate holes is 1 mm to 5 mm;

[0019] The distance between the tip of the nanowire array and the gate is 50 microns to 500 microns.

[0020] Optionally, in the space propulsion system, the base is formed of an insulating material into a cylindrical structure with a middle depression, and a first boss and a second boss are formed at the edge of the base. The height of the first boss is lower than the height of the second boss. The nanowire array assembly is placed on the first boss, and the second boss surrounds the outer wall of the nanowire array assembly;

[0021] The distance between the lower surface of the nanowire array assembly and the bottom surface of the base is 5 mm to 10 mm;

[0022] The bottom surface of the base has a number of uniformly distributed air supply holes penetrating the height direction of the base, and the air supply holes are connected to the air supply pipeline; the hole diameter of the air supply holes is 0.5 mm to 2 mm.

[0023] Optionally, in the space propulsion system, the nanowire array is applied with a positive voltage and the gate is grounded;

[0024] The gas flows from the air supply pipeline through the air supply holes, the gap between the nanowire array assembly and the base, the flow channel, and finally flows near the tip of the nanowire array, is ionized by the strong electric field at the tip of the nanowire array, and is accelerated and ejected by the strong electric field to generate thrust.

[0025] The present invention also provides a propulsion method for a space propulsion system, and the propulsion method for the space propulsion system includes:

[0026] The space propulsion system carries the original propellant, and the space propulsion system ionizes the original propellant to generate thrust for the orbit maintenance or transfer of a very low orbit satellite or a planetary probe;

[0027] The air intake device of the space propulsion system collects the gas in the orbit as the new propellant;

[0028] The gas is supplied to the nanowire array ion thruster through a gas supply pipeline, ionized by the strong electric field of the nanowire array ion thruster, and accelerated by the strong electric field and ejected to generate thrust;

[0029] The material of the nanowire array ion thruster is an oxide.

[0030] Optionally, in the propulsion method of the space propulsion system, the plume electro-neutralization mode of the nanowire array ion thruster includes:

[0031] The mutual neutralization mode of two thrusters. When in the mutual neutralization mode of the two thrusters, the first nanowire array ion thruster emits cations, and the second nanowire array ion thruster emits electrons to make the overall plume electro-neutral;

[0032] The self-neutralization mode of one thruster. When in the self-neutralization mode of one thruster, the nanowire array ion thruster periodically emits cations or electrons to maintain the overall electro-neutrality of the plume.

[0033] Optionally, in the propulsion method of the space propulsion system, the plume electro-neutralization mode of the nanowire array ion thruster includes:

[0034] When the solenoid valve for supplying gas to the nanowire array ion thruster is in the open state, a positive voltage is applied to the nanowire array, the grid is grounded, and the nanowire array ion thruster emits cations;

[0035] When the solenoid valve for supplying gas to the nanowire array ion thruster is in the closed state, a negative voltage is applied to the nanowire array, the grid is grounded, and the nanowire array ion thruster emits electrons.

[0036] In the space propulsion system and its propulsion method provided by the present invention, as a propulsion system for ultra-low orbit satellites or planetary probes with an atmosphere, the air intake device collects the gas in the orbit as a new propellant. The gas is supplied to the nanowire array ion thruster through a gas supply pipeline, ionized by the strong electric field of the nanowire array ion thruster, and accelerated and ejected by the strong electric field to generate thrust. The material of the nanowire array ion thruster is an oxide, realizing that the gas can be continuously supplied to the nanowire array ion thruster as a propellant, greatly increasing the service life of the nanowire array ion thruster; since the ultra-low orbit contains rarefied air and some interstellar planets are similar to the Earth and have an atmosphere, therefore, collecting the gas in the orbit as a propellant through the air intake device can provide a continuous power source for ultra-low orbit satellites and planetary probes.

[0037] In addition, by using an oxide as the manufacturing material for the nanowire array ion thruster, it avoids the defect that conventional electric propulsion, such as traditional Hall thrusters and ion thrusters, uses inert gases such as xenon as propellants, and its cathode is vulnerable to poisoning by atomic oxygen, oxygen, etc. and is not suitable for air-breathing electric propulsion.

[0038] Furthermore, by using an oxide as the manufacturing material for the nanowire array ion thruster, it avoids the defect that in the prior art, the thruster based on a carbon nanotube array is damaged due to the presence of a large amount of oxygen and atomic oxygen in the ultra-low orbit, and the carbon nanotubes are easily corroded by oxygen and atomic oxygen. Therefore, the oxide-based nanowire array thruster of the present invention is more suitable for air-breathing electric propulsion.

[0039] Among them, the nanowire array is a MEMS nanowire array. MEMS is the full name of "Micro-Electro-Mechanical System", and its Chinese name is "Micro-Electro-Mechanical System". MEMS devices have many advantages such as small volume, light weight, low energy consumption, and small inertia, and are widely used in microelectronics, materials, mechanics, chemistry, machinery, aerospace and other fields.

[0040] The oxide-based nanowire array ion thruster of the present invention is a new type of electric propulsion that integrates MEMS technology, field emission principle and ion electric propulsion concept. It has the advantages of oxidation resistance, high specific impulse, wide thrust range, and can use any gas as a propellant. It can not only use the propellant carried by itself like conventional electric propulsion, but also collect the gas in the orbit and apply it to the propulsion system of ultra-low orbit satellites and planetary probes with an atmosphere, so as to greatly extend the life of spacecraft. Description of the Drawings

[0041] Figure 1 It is a schematic diagram of the assembly relationship of each part of the nanowire array ion thruster of the space propulsion system according to an embodiment of the present invention;

[0042] Figure 2 It is a schematic diagram of the overall assembly appearance of the nanowire array ion thruster of the space propulsion system according to an embodiment of the present invention;

[0043] Figure 3 It is a schematic cross-sectional view of the nanowire array ion thruster of the space propulsion system according to an embodiment of the present invention;

[0044] Figure 4 It is a schematic structural diagram of the nanowire array assembly of the space propulsion system according to an embodiment of the present invention;

[0045] Figure 5 It is a schematic diagram of the gate structure of the space propulsion system according to an embodiment of the present invention;

[0046] As shown in the figure: 1 - gate retaining ring; 11 - gate snap ring; 2 - gate; 21 - gate hole; 3 - insulating support; 31 - component snap ring; 4 - nanowire array component; 5 - nanowire array; 6 - substrate; 7 - flow channel; 8 - base; 81 - first boss; 82 - second boss; 83 - air supply hole. Detailed implementation manners

[0047] The following further elaborates on the space propulsion system and its propulsion method proposed by the present invention in conjunction with the accompanying drawings and specific embodiments. According to the following description and claims, the advantages and features of the present invention will be clearer. It should be noted that the accompanying drawings are all in a very simplified form and use non-precise scales, only for the purpose of facilitating and clearly assisting in explaining the purpose of the embodiments of the present invention.

[0048] The core idea of the present invention is to provide a space propulsion system and its propulsion method to solve the problem that the limited weight of the propellant carried by the existing thruster affects its service life.

[0049] To achieve the above idea, the present invention provides a space propulsion system and its propulsion method. The space propulsion system is used as the propulsion system of an ultra-low orbit satellite or a planetary probe with an atmosphere. The space propulsion system includes an air intake device, a gas supply pipeline, and a nanowire array ion thruster, where: the air intake device collects the gas in the orbit as the propellant; the gas is provided to the nanowire array ion thruster by the gas supply pipeline, ionized by the strong electric field of the nanowire array ion thruster, and accelerated and ejected by the strong electric field to generate thrust; the material of the nanowire array ion thruster is an oxide.

[0050] <Example 1>

[0051] This embodiment provides a space propulsion system. The space propulsion system serves as a propulsion system for a very low orbit satellite or a planetary probe with an atmosphere. The space propulsion system includes an air intake device, a gas supply pipeline, and a nanowire array ion thruster, where: the air intake device collects the gas in the orbit as a propellant; the gas is supplied to the nanowire array ion thruster through the gas supply pipeline, ionized by the strong electric field of the nanowire array ion thruster, and accelerated and ejected by the strong electric field to generate thrust; the material of the nanowire array ion thruster is an oxide.

[0052] As Figures 1 to 3 shown, in the space propulsion system, the nanowire array ion thruster includes a grid retaining ring 1, a grid 2, an insulating support 3, a nanowire array component 4, and a base 8 that are sequentially and cooperatively connected from top to bottom, where: the grid retaining ring 1 is an annular part made of an insulating material; the insulating support 3 is an annular structure for electrical insulation between the grid 2 and the nanowire array component 4; the nanowire array component 4 is placed on the base 8, the insulating support 3 clamps the nanowire array component 4 tightly, and the nanowire array component 4 is pressed by a component snap ring 31 to prevent it from loosening. The grid 2 is placed on the upper edge of the insulating support 3, the grid retaining ring 1 is fixed to the edge of the grid 2, and the grid 2 is stuck in the grid retaining ring 1 and pressed by the grid retaining ring, that is, it is pressed by a grid snap ring 11 to prevent it from loosening.

[0053] As Figure 1 、 3 or 4 shown, in the space propulsion system, the nanowire array component 4 is an integrated configuration composed of a substrate 6, a nanowire array 5, and a flow channel 7; the substrate 6 is a circular thin sheet made of silicon, ceramic, or stainless steel; the bottom surface of the substrate 6 is parallel to the grid 2 and the base 8; the nanowire array 5 grows from the substrate 6, including but not limited to zinc oxide nanowires, tungsten oxide nanowires, copper oxide nanowires, or titanium dioxide nanowires; the flow channel 7 is a uniformly distributed hole penetrating the height direction of the substrate 6; the hole diameter of the flow channel 7 is 10 micrometers to 100 micrometers.

[0054] As Figure 5 shown, in the space propulsion system, the material of the grid 2 is a sputtering-resistant metal, such as tungsten, molybdenum, or carbon. The shape of the grid 2 is a circular thin sheet structure. The grid 2 is distributed with grid holes 21 penetrating the height direction of the grid 2. The grid holes 21 serve as channels for ions to be accelerated and ejected. The hole diameter of the grid holes 21 is 1 millimeter to 5 millimeters; the distance between the tip of the nanowire array 5 and the grid 2 is 50 micrometers to 500 micrometers.

[0055] As Figure 3As shown, in the space propulsion system, the base 8 is formed of an insulating material into a cylindrical structure with a middle depression, and a first boss 81 and a second boss 82 are formed at the edge of the base 8. The height of the first boss 81 is lower than that of the second boss 82. The nanowire array assembly 4 is placed on the first boss 81, and the second boss 82 surrounds the outer sidewall of the nanowire array assembly 4. The distance between the lower surface of the nanowire array assembly 4 and the bottom surface of the base 8 is 5 mm to 10 mm. A plurality of air supply holes 83 are uniformly distributed on the bottom surface of the base 8 and penetrate through the height direction of the base 8. The air supply holes 83 are connected to the air supply pipeline. The hole diameter of the air supply holes 83 is 0.5 mm to 2 mm.

[0056] Further, in the space propulsion system, a positive voltage is applied to the nanowire array 5, and the gate 2 is grounded. The gas flows from the air supply pipeline through the air supply holes, the gap between the nanowire array assembly 4 and the base 8, and the flow channel 7 in sequence, and finally flows near the tip of the nanowire array 5. It is ionized by the strong electric field at the tip of the nanowire array 5 and is accelerated by the strong electric field and ejected to generate thrust.

[0057] In summary, the above embodiments have described in detail different configurations of the space propulsion system. Of course, the present invention includes but is not limited to the configurations listed in the above embodiments. Any content transformed on the basis of the configurations provided in the above embodiments belongs to the scope protected by the present invention. Those skilled in the art can draw inferences from the content of the above embodiments.

[0058] <Embodiment 2>

[0059] This embodiment provides a propulsion method for a space propulsion system. The propulsion method of the space propulsion system includes: the space propulsion system carries the original propellant, and the space propulsion system ionizes the original propellant to generate thrust for the orbit maintenance or transfer of a low-earth orbit satellite or a planetary probe; the air intake device of the space propulsion system collects the gas in the orbit as the new propellant; the gas is provided by the air supply pipeline to the nanowire array ion thruster, is ionized by the strong electric field of the nanowire array ion thruster, and is accelerated by the strong electric field and ejected to generate thrust; the material of the nanowire array ion thruster is an oxide.

[0060] Specifically, in the propulsion method of the space propulsion system described above, the plume electro-neutralization mode of the nanowire array ion thruster includes: the mutual neutralization mode of two thrusters. When in the mutual neutralization mode of the two thrusters, the first nanowire array ion thruster emits cations, and the second nanowire array ion thruster emits electrons, so that the overall plume is electro-neutral; the self-neutralization mode of one thruster. When in the self-neutralization mode of one thruster, the nanowire array ion thruster periodically emits cations or electrons to maintain the overall electro-neutrality of the plume.

[0061] Furthermore, in the propulsion method of the space propulsion system described above, the plume electro-neutralization mode of the nanowire array ion thruster includes: when the solenoid valve supplying gas to the nanowire array ion thruster is in the open state, a positive voltage is applied to the nanowire array 5, the grid 2 is grounded, and the nanowire array ion thruster emits cations; when the solenoid valve supplying gas to the nanowire array ion thruster is in the closed state, a negative voltage is applied to the nanowire array 5, the grid 2 is grounded, and the nanowire array ion thruster emits electrons.

[0062] In the space propulsion system and its propulsion method provided by the present invention, the space propulsion system is used as the propulsion system of an ultra-low orbit satellite or a planetary probe with an atmosphere. The air intake device collects the gas in the orbit as a new propellant. The gas is supplied to the nanowire array ion thruster through the gas supply pipeline, ionized by the strong electric field of the nanowire array ion thruster, and accelerated and ejected by the strong electric field to generate thrust. The material of the nanowire array ion thruster is an oxide, which realizes that the gas can be continuously supplied to the nanowire array ion thruster as a propellant, greatly increasing the service life of the nanowire array ion thruster; because the ultra-low orbit contains thin air and some interstellar planets are similar to the Earth and have an atmosphere, therefore, collecting the gas in the orbit as a propellant through the air intake device can provide a continuous power source for ultra-low orbit satellites and planetary probes.

[0063] In addition, by using an oxide as the manufacturing material for the nanowire array ion thruster, it avoids the defect that conventional electric propulsion, such as traditional Hall thrusters, ion thrusters, etc., use inert gases such as xenon as propellants, and their cathodes are vulnerable to poisoning by atomic oxygen, oxygen, etc. and are not suitable for air-breathing electric propulsion.

[0064] Furthermore, by using an oxide as the manufacturing material for the nanowire array ion thruster, it avoids the defect that in the prior art, the thruster based on a carbon nanotube array is damaged due to the large amount of oxygen and atomic oxygen in the ultra-low orbit, and the carbon nanotubes are easily corroded by oxygen and atomic oxygen. Therefore, the oxide-based nanowire array thruster of the present invention is more suitable for air-breathing electric propulsion.

[0065] Among them, the nanowire array is a MEMS nanowire array. MEMS stands for "Micro-Electro-Mechanical System", and its Chinese name is "Micro-Electro-Mechanical System". MEMS devices have many advantages such as small size, light weight, low energy consumption, and small inertia, and are widely used in microelectronics, materials, mechanics, chemistry, machinery, aerospace and other fields.

[0066] The oxide-based nanowire array ion thruster of the present invention is a new type of electric thruster that integrates MEMS technology, field emission principle and ion electric propulsion concept. It has the advantages of oxidation resistance, high specific impulse, wide thrust range, and can use any gas as a propellant. It can not only use the propellant carried by itself like a conventional electric thruster, but also collect the gas in the orbit and apply it to the propulsion system of ultra-low orbit satellites and planetary probes with an atmosphere, so as to greatly extend the life of spacecraft.

[0067] In this specification, each embodiment is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. The same or similar parts among the embodiments can be referred to each other. For the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the description of the method part.

[0068] The above description is only a description of the preferred embodiments of the present invention, and does not limit the scope of the present invention in any way. Any changes and modifications made by those of ordinary skill in the art of the present invention according to the above disclosure shall fall within the protection scope of the claims.

Claims

1. A space propulsion system, characterized in that, The space propulsion system serves as the propulsion system for ultra-low orbit satellites or planetary probes with an atmosphere. The space propulsion system includes an air intake device, a gas supply pipeline, and a nanowire array ion thruster, where: The air intake device collects the gas in the orbit as the propellant; The gas is supplied to the nanowire array ion thruster by the gas supply pipeline, ionized by the strong electric field of the nanowire array ion thruster, and accelerated by the strong electric field and ejected to generate thrust; The material of the nanowire array ion thruster is an oxide to prevent the nanowire array ion thruster from being corroded by atomic oxygen or oxygen in the ultra-low orbit. The nanowire array component of the nanowire array ion thruster is an integrated configuration composed of a substrate, a nanowire array, and a flow channel. The material of the substrate is ceramic, and the nanowires grow from the ceramic substrate. The nanowire array includes zinc oxide nanowires, tungsten oxide nanowires, copper oxide nanowires, or titanium dioxide nanowires.

2. The space propulsion system according to claim 1, wherein The nanowire array ion thruster includes a gate retainer, a gate, an insulating support, a nanowire array component, and a base that are sequentially and cooperatively connected from top to bottom, where: The gate retainer is an annular part made of an insulating material; The insulating support is in a ring structure for electrical insulation between the gate and the nanowire array component; The nanowire array component is placed on the base. The insulating support clamps the nanowire array component tightly. The gate is placed on the upper edge of the insulating support. The gate retainer is fixed to the edge of the gate, and the gate is stuck in the gate retainer and pressed by the gate retainer.

3. The space propulsion system according to claim 2, wherein The material of the gate is tungsten, molybdenum, or carbon. The shape of the gate is a circular thin plate structure. Gate holes penetrating the height direction of the gate are distributed on the gate. The gate holes serve as channels for ions to be accelerated and ejected. The pore diameter of the gate holes is 1 mm to 5 mm; The distance between the tip of the nanowire array and the gate is 50 μm to 500 μm.

4. The space propulsion system according to claim 3, characterized in that, The base is formed of an insulating material into a cylindrical structure with a middle depression, and a first boss and a second boss are formed at the edge of the base. The height of the first boss is lower than the height of the second boss. The nanowire array component is placed on the first boss, and the second boss surrounds the outer sidewall of the nanowire array component; The distance between the lower surface of the nanowire array component and the bottom surface of the base is 5 mm to 10 mm; A plurality of air supply holes that are evenly distributed and penetrate the height direction of the base are provided on the bottom surface of the base. The air supply holes are connected to the gas supply pipeline; the pore diameter of the air supply holes is 0.5 mm to 2 mm.

5. The space propulsion system according to claim 4, characterized in that, A positive voltage is applied to the nanowire array, and the gate is grounded; The gas passes through the air supply holes, the gap between the nanowire array component and the base, the flow channel in sequence through the gas supply pipeline, and finally flows near the tip of the nanowire array, is ionized by the strong electric field at the tip of the nanowire array, and is accelerated by the strong electric field and ejected to generate thrust.

6. A propulsion method for a space propulsion system, characterized in that, The propulsion method of the space propulsion system includes: The space propulsion system carries the original propellant, and the space propulsion system ionizes the original propellant to generate thrust for the orbit maintenance or transfer of ultra-low orbit satellites or planetary probes; The air intake device of the space propulsion system collects the gas in the orbit as the new propellant; The gas is supplied to the nanowire array ion thruster through the gas supply pipeline, ionized by the strong electric field of the nanowire array ion thruster, and accelerated by the strong electric field and ejected to generate thrust; The material of the nanowire array ion thruster is an oxide to prevent the nanowire array ion thruster from being corroded by atomic oxygen or oxygen in the ultra-low orbit, wherein the nanowire array component of the nanowire array ion thruster is an integrated configuration composed of a substrate, a nanowire array and a flow channel, and the substrate is made of ceramic, and the nanowires grow from the ceramic substrate, and the nanowire array includes zinc oxide nanowires, tungsten oxide nanowires, copper oxide nanowires or titanium dioxide nanowires.

7. The propulsion method of the space propulsion system according to claim 6, characterized in that, The plume electro-neutralization mode of the nanowire array ion thruster includes: The mutual neutralization mode of two thrusters. When in the mutual neutralization mode of the two thrusters, the first nanowire array ion thruster emits cations, and the second nanowire array ion thruster emits electrons to make the plume as a whole electro-neutral; The self-neutralization mode of one thruster. When in the self-neutralization mode of the one thruster, the nanowire array ion thruster periodically emits cations or electrons to keep the plume as a whole electro-neutral.

8. The propulsion method of the space propulsion system according to claim 7, characterized in that, The plume electro-neutralization mode of the nanowire array ion thruster includes: When the solenoid valve for supplying gas to the nanowire array ion thruster is in the open state, a positive voltage is applied to the nanowire array, the grid is grounded, and the nanowire array ion thruster emits cations; When the solenoid valve for supplying gas to the nanowire array ion thruster is in the closed state, a negative voltage is applied to the nanowire array, the grid is grounded, and the nanowire array ion thruster emits electrons.

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