Thrust-adjustable microwave chemical thruster

Abstract

The invention discloses a microwave chemical thruster with adjustable thrust. The microwave chemical thruster comprises a microwave source, a microwave energy coupler, a connecting mechanism, a Laval nozzle, a medicine blocking ring, a combustion chamber, a microwave sensitive propellant, a heat insulation layer, a rubber sealing ring and a fuel gas transition arc block. According to the invention, the solid chemical propellant is coupled with the physical field microwaves, the propellant is subjected to non-self-sustaining combustion, and the microwave radiation energy is adjusted, so that the operations such as multi-time ignition and flameout and combustion speed adjustment of the solid propellant can be realized, and the thruster has the capability of adjusting the thrust in real time. According to the thrust-adjustable microwave chemical thruster, mN-N magnitude thrust can be generated, and the power requirements of attitude control and orbit change of a spacecraft can be met.

Description

Technical Field

[0001] The invention relates to the field of aerospace propulsion technology, and in particular to a microwave chemical thruster with adjustable thrust. Background Art

[0002] With the vigorous development of the aerospace field, spacecraft technology has been continuously improved and perfected, and higher requirements have been put forward for the propulsion system that provides power for it. For example, small spacecraft such as micro-nano satellites need to frequently implement operations such as orbit change, formation flight, and attitude adjustment, requiring the propulsion system to have the function of repeated start-up and adjustable thrust. At present, the commonly used thrusters for spacecraft are cold gas thrusters and electric thrusters. Among them, cold gas thrusters use inert gas as propellant. The high-pressure gas stored in the high-pressure gas storage tank is decompressed and stabilized through the vent valve and the voltage stabilizing component. The gas generates the required thrust through the solenoid valve switch, which can realize repeated work of the thruster. However, the cold gas thruster has a low specific impulse, and the propulsion system needs to be equipped with a high-pressure gas storage device with a large mass. In addition, the gas is stored in the high-pressure gas storage tank, and the molecular diffusion is high, so it is difficult to avoid gas leakage. Electric thrusters generate thrust by heating or directly accelerating the working fluid to form a high-speed jet. The power supply system can control the thrusters to work repeatedly, but the charged particles produced by the ionization of the electric thrusters will have a negative effect on the thruster walls. At the same time, their thrust is small and the thrust-to-weight ratio is low. Compared with traditional chemical propulsion, it takes more time to complete the same orbit change operation.

[0003] Solid chemical thrusters have advantages such as high thrust and simple propulsion system structure. However, affected by the self-sustaining combustion properties of traditional solid propellants, the solid chemical thrusters currently used have the disadvantage of difficulty in propellant extinguishing after ignition, and it is difficult to actively control the combustion process of the propellant. Therefore, the thrust of solid chemical thrusters is difficult to actively and randomly control, which seriously limits the application of solid chemical thrusters in space vehicle maneuvering and trajectory changing. Summary of the invention

[0004] Aiming at the current situation that the thrust of traditional solid chemical thrusters is difficult to adjust in real time, the present invention proposes a microwave chemical thruster with adjustable thrust, which can generate thrust in the order of mN to N and meet the power requirements of attitude control and orbit change of spacecraft.

[0005] The technical solution of the present invention is:

[0006] A microwave chemical thruster with adjustable thrust controls the combustion state of solid propellant by coupling external energy microwaves, realizes controllable burnout and adjustable burning rate through the propellant, and further realizes adjustable thrust of the thruster.

[0007] The thrust-adjustable microwave chemical thruster comprises a microwave source, a microwave energy coupler, a connecting mechanism, a Laval nozzle, a charge retaining ring, a combustion chamber, a microwave-sensitive propellant, a thermal insulation layer, a rubber sealing ring and a gas transition arc block.

[0008] In the above-mentioned microwave chemical thruster with adjustable thrust, the microwave source radiates microwave energy to the microwave sensitive propellant through the microwave energy coupler to achieve non-self-sustaining combustion of the propellant.

[0009] In the above-mentioned microwave chemical thruster with adjustable thrust, the connecting mechanism is fixedly connected to the microwave energy coupler, the Laval nozzle, and the combustion chamber, and rubber sealing rings are used to seal between the connecting mechanism and the Laval nozzle, and between the connecting mechanism and the combustion chamber.

[0010] In the above-mentioned microwave chemical thruster with adjustable thrust, the microwave sensitive propellant is placed in the combustion chamber, and the two are insulated by a heat insulation layer. The heat insulation layer is placed coaxially with the microwave sensitive propellant and the combustion chamber, and the heat insulation layer is bonded to the combustion chamber. The retaining ring fixes the position of the microwave sensitive propellant in the combustion chamber.

[0011] In the above-mentioned microwave chemical thruster with adjustable thrust, the gas transition arc block is placed in the gas channel in the connecting mechanism, and the gas generated by the combustion of the microwave sensitive propellant is moderated by the gas transition arc block and then transitioned to the Laval nozzle.

[0012] In the above-mentioned microwave chemical thruster with adjustable thrust, the microwave sensitive propellant is calculated by mass percentage, and the oxidant is 65% to 75%, the binder is 15% to 20%, the cross-linking agent is 1% to 2%, the conductive agent is 3% to 5%, and the microwave energy absorber is 5% to 10%. The oxidant is hydroxylamine nitrate (HAN) or ammonium dinitramide (ADN), the binder is polyvinyl alcohol (PVA), the cross-linking agent is boric acid, the conductive agent is metal aluminum powder, tungsten powder or non-metal graphene, carbon nanotubes, and the microwave energy absorber is glycerol or n-butanol.

[0013] In the above-mentioned microwave chemical thruster with adjustable thrust, the combustion chamber is a metal shell.

[0014] In the above-mentioned microwave chemical thruster with adjustable thrust, the insulation layer is made of phenolic-asbestos material.

[0015] Compared with the prior art, the advantages of the present invention are:

[0016] 1. The microwave chemical thruster with adjustable thrust of the present invention adopts a combination of a microwave source and a microwave sensitive propellant. The microwave source radiates microwave energy to realize controllable combustion of the propellant. The thrust range of the thruster is in the order of mN to N, which meets the power requirements of attitude control and orbit change of spacecraft.

[0017] 2. The thrust-adjustable microwave chemical thruster of the present invention uses a microwave-sensitive propellant with non-self-sustaining combustion. The propellant burns under microwave irradiation and extinguishes after the microwave source is turned off. When the microwave source is turned on again, the propellant is ignited again, so that the thruster can be started repeatedly.

[0018] 3. The thrust-adjustable microwave chemical thruster of the present invention can adjust the burning rate of the propellant by changing the microwave energy radiated on the microwave-sensitive propellant, thereby adjusting the thrust of the thruster in real time.

[0019] 4. The thrust-adjustable microwave chemical thruster of the present invention uses solid propellant. Compared with liquid and paste propellants, it does not need to use a booster device and a valve, etc., which reduces the complexity of the thruster and improves the safety of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the working mode of the thrust-controllable microwave chemical thruster of the present invention.

[0021] Figure 2 This is a cross-sectional view of the thrust-controllable microwave chemical propulsion system of the present invention.

[0022] Figure 3 This is a three-dimensional diagram of the thrust-controllable microwave chemical thruster of the present invention. DETAILED DESCRIPTION

[0023] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0024] See also Figure 1 When a spacecraft performs attitude adjustment or orbit change and deorbit missions, the thruster is required to provide continuously adjustable thrust. At this time, the microwave chemical thruster with controllable thrust uses microwaves to control the combustion of microwave-sensitive propellants. Under the action of microwave radiation, the microwave-sensitive propellants burn non-self-sustainingly in the combustion chamber, and the combustion gas is accelerated and ejected through the Laval nozzle, thereby generating a thrust of the order of mN to N.

[0025] The above-mentioned microwave chemical thruster with controllable thrust can realize controllable combustion of the propellant by controlling whether the microwave source applies microwave radiation to the propellant, thereby controlling the startup work of repeated ignition and extinction of the thruster.

[0026] The above-mentioned thrust-controllable microwave chemical thruster can adjust the burning rate of the propellant by adjusting the microwave energy radiated on the propellant, thereby controlling the thrust regulation of the thruster.

[0027] See also Figure 2The thrust-adjustable microwave chemical thruster of the present invention comprises a microwave source 1, a microwave energy coupler 2, a connecting mechanism 3, a Laval nozzle 4, a charge retaining ring 5, a combustion chamber 6, a microwave-sensitive propellant 7, an insulating layer 8, a rubber sealing ring 9 and a gas transition arc block 10.

[0028] The microwave source 1 is connected to the microwave energy coupler 2, the connecting mechanism 3, the Laval nozzle 4, and the combustion chamber 6 in sequence.

[0029] The microwave sensitive propellant 7 is arranged in the combustion chamber 6 , a heat insulating layer 8 is arranged outside the microwave sensitive propellant 7 , and a medicine retaining ring 5 is arranged between the Laval nozzle 4 and the microwave sensitive propellant 7 in the combustion chamber 6 .

[0030] The microwave frequency generated by the microwave source 1 is between 3 GHz and 300 GHz. The microwave is radiated onto the microwave sensitive propellant 7 through the microwave energy coupler 2 to ignite and control the combustion of the microwave sensitive propellant 7 .

[0031] The radiation surface of the microwave energy coupler 2 is coaxially arranged with the burning surface of the microwave sensitive propellant 7 , ensuring that the energy of the microwave radiation can cover the burning surface of the microwave sensitive propellant 7 .

[0032] The microwave energy coupler 2, the Laval nozzle 4, the combustion chamber 6 and the connecting mechanism 3 are fixedly connected by threads, wherein the Laval nozzle 4 and the connecting mechanism 3, and the combustion chamber 6 and the connecting mechanism 3 are sealed by rubber sealing rings 9 respectively.

[0033] The gas transition arc block 10 is placed in the gas channel of the connecting mechanism 3, and the arc surface of the gas transition arc block 10 is opposite to the combustion surface of the microwave sensitive propellant 7. When the gas transitions to the Laval nozzle 4 through the channel in the connecting mechanism 3, the gas transition arc block 10 can be used to ease the gas flow, avoid gas backflow, and reduce thrust loss.

[0034] The Laval nozzle 4 is a convergent-divergent nozzle, which includes two sections: one section is a convergent section, and the preferred convergence angle is 60° to 90°, and the other section is a divergent section, and the preferred divergent angle is 20° to 30°. The throat diameter between the two sections is 1.5 mm to 32 mm. The diameter of the convergent section gradually decreases from the inside to the outside, and is used to gather the combustion gas. The divergent section contacts the external environment and is used to accelerate the combustion gas.

[0035] The above-mentioned medicine retaining ring 5, combustion chamber 6, microwave-sensitive propellant 7, and heat-insulating layer 8 are coaxially arranged. The microwave-sensitive propellant 7 is placed in the combustion chamber 6, and the two are insulated by the heat-insulating layer 8, wherein the heat-insulating layer 8 is bonded to the inner wall of the combustion chamber 6, and the heat-insulating layer is a phenolic-asbestos material. The medicine retaining ring 5 can fix the microwave-sensitive propellant 7.

[0036] The microwave sensitive propellant 7 is composed of an oxidant, a binder, a cross-linking agent, a conductive agent and a microwave energy absorber. In terms of mass percentage, the oxidant is 65% to 75%, the binder is 15% to 20%, the cross-linking agent is 1% to 2%, the conductive agent is 3% to 5%, and the microwave energy absorber is 5% to 10%. Preferably, the oxidant ammonium dinitramide (ADN) accounts for 72% of the microwave sensitive propellant 7, the binder polyvinyl alcohol (PVA) accounts for 15% of the microwave sensitive propellant 7, the cross-linking agent boric acid accounts for 1.5% of the microwave sensitive propellant 7, the conductive agent carbon nanotubes accounts for 3.5% of the microwave sensitive propellant 7, and the microwave energy absorber glycerol accounts for 8% of the microwave sensitive propellant 7.

[0037] See also Figure 3 Except for the microwave source 1, the thrust-controllable microwave chemical thruster of the present invention is cylindrical as a whole, can be conveniently installed at various positions of the spacecraft, and can change the direction of the thrust by adjusting the direction of the Laval nozzle.

Claims

1. A microwave chemical thruster with adjustable thrust, characterized in that: The thruster includes: A microwave source (1); the microwave source (1) irradiates microwaves to a microwave-sensitive propellant, and the propellant undergoes non-self-sustaining combustion in the microwave irradiation region; The propellant burnout can be controlled by turning the microwave source on or off, so that the thruster can be started repeatedly. By changing the microwave energy radiated on the microwave sensitive propellant, the burning rate of the propellant can be adjusted, thereby adjusting the thrust of the thruster in real time; The microwave source (1) is sequentially connected to a microwave energy coupler (2), a connecting mechanism (3), a Laval nozzle (4), and a combustion chamber (6); The microwave sensitive propellant (7) is arranged in the combustion chamber (6), a heat insulating layer (8) is arranged outside the microwave sensitive propellant (7), and a medicine retaining ring (5) is arranged between the Laval nozzle (4) and the microwave sensitive propellant (7) in the combustion chamber (6).

2. The microwave chemical thruster with adjustable thrust according to claim 1, characterized in that: The microwave energy coupler (2), the Laval nozzle (4), the combustion chamber (6) and the connecting mechanism (3) are fixedly connected via threads, wherein the Laval nozzle (4) and the connecting mechanism (3), and the combustion chamber (6) and the connecting mechanism (3) are sealed respectively by rubber sealing rings (9).

3. The microwave chemical thruster with adjustable thrust according to claim 1, characterized in that: The microwaves emitted by the microwave source (1) are radiated onto the microwave sensitive propellant (7) through the microwave energy coupler (2).

4. The microwave chemical thruster with adjustable thrust according to claim 1 or 3, characterized in that: The radiation surface of the microwave energy coupler (2) and the combustion surface of the microwave sensitive propellant (7) are arranged coaxially, and the microwave radiation surface is larger than the combustion surface of the microwave sensitive propellant (7).

5. The microwave chemical thruster with adjustable thrust according to claim 1, characterized in that: The oxidant of the microwave sensitive propellant (7) is hydroxylamine nitrate HAN or ammonium dinitramide ADN, the binder is polyvinyl alcohol PVA, the cross-linking agent is boric acid, the conductive agent is metal aluminum powder, tungsten powder or non-metal graphene, carbon nanotubes, and the microwave energy absorber is glycerol or n-butanol.

6. The microwave chemical thruster with adjustable thrust according to claim 1, characterized in that: The gas transition arc block (10) is placed in the gas channel in the connection mechanism (4), and the gas generated by the combustion of the microwave sensitive propellant (7) is moderated by the gas transition arc block (10) and then transitioned to the Laval nozzle (4).

7. The microwave chemical thruster with adjustable thrust according to claim 1, characterized in that: The Laval nozzle (4) is a convergent-divergent nozzle, comprising two sections: one section is a convergent section, with a convergence angle of 60° to 90°, and the other section is a divergent section, with a divergent angle of 20° to 30°. The throat diameter between the two sections is 1.5 mm to 32 mm. The diameter of the convergent section gradually decreases from the inside to the outside, and is used to gather the combustion gas. The divergent section is in contact with the external environment, and is used to accelerate the combustion gas.

8. The microwave chemical thruster with adjustable thrust according to claim 1, characterized in that: The charge retaining ring (5), the combustion chamber (6), the microwave-sensitive propellant (7), and the heat insulating layer (8) are coaxially arranged.

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