Target type atomization electric ignition single-component rocket engine

Abstract

The invention discloses a target type atomization electric ignition single-component rocket engine which comprises an injector, an electric arc ignition device and a combustion chamber shell, an inlet of the injector is connected with a propellant storage tank through an electromagnetic valve, a target surface structure is correspondingly arranged at an outlet position of the injector at an interval, and the arc ignition device is connected with the combustion chamber shell. The target surface structure is used for atomizing high-speed propellant jet flow which is ejected from an outlet of the injector and impacts on the target surface structure into tiny liquid drops, the electric arc ignition device is fixedly connected with the injector, and the combustion chamber shell is fixedly connected to the outlet end of the injector. An outlet of the injector and an outlet of the electric arc ignition device are both communicated with the interior of the combustion chamber shell. The target type atomization electric ignition single-component rocket engine is simple in structure, high in working stability, high in combustion efficiency, high in startup and shutdown response speed and capable of adapting to various single-component propellants.

Description

Technical Field

[0001] The invention relates to the field of aerospace, and in particular provides a target-type atomizing electric ignition monopropellant rocket engine. Background Art

[0002] With the rapid development of commercial aerospace, requirements have been put forward for engines such as low cost, fast response, short development and production cycle, high reliability, and adaptability to different non-toxic chemical propellants. Among them, bipropellant rocket engines can meet the requirements of fast response, but they mostly use propellants that ignite on contact (but are toxic), such as nitrogen tetroxide, methyl hydrazine, etc.; after years of technical accumulation, the propellants of monopropellant rocket engines have non-toxic or low-toxic monopropellants such as HAN (hydroxylamine nitrate) base, ADN (ammonium dinitramide) base, and oxygen-fuel integrated (NOFBx). However, existing monopropellant engines all use catalytic decomposition to ignite, and their structures include main components such as solenoid valves, showerhead injectors, catalytic beds, and nozzles. Among them, the showerhead injector divides an upstream stream of propellant into multiple streams through multiple capillaries. Affected by the process, the propellants in each capillary are uneven, resulting in uneven propellant distribution, which can easily cause uneven flame front energy and poor working stability. The catalytic bed has a complex structure, low combustion efficiency, slow on / off response speed, and needs to use a catalyst that matches the propellant type and working characteristics. The development cycle is long and the cost is high.

[0003] Therefore, it has become an urgent problem to propose a new type of monopropellant rocket engine to simplify its structure, improve working stability, combustion efficiency, power on and off response speed, and improve propellant adaptability. Summary of the invention

[0004] In view of this, the object of the present invention is to provide a target-type atomizing electric-ignition monopropellant rocket engine to solve the problems existing in traditional monopropellant rocket engines.

[0005] The technical solution provided by the present invention is: a target-type atomizing electric-ignition monopropellant rocket engine, comprising: an injector, an arc ignition device and a combustion chamber shell, wherein the inlet of the injector is connected to the propellant tank through an electromagnetic valve, the outlet position of the injector corresponds to and is spaced apart from a target surface structure, the target surface structure is used to atomize the high-speed propellant jet ejected from the outlet of the injector and impacting the target surface structure into tiny droplets, the arc ignition device is fixedly connected to the injector, the combustion chamber shell is fixedly connected to the outlet end of the injector, and the outlet of the injector and the outlet of the arc ignition device are both connected to the inside of the combustion chamber shell.

[0006] Preferably, a throttle ring is installed at the inlet end of the injector, a first through hole is provided in the middle of the throttle ring, and the outlet of the solenoid valve is connected with the outlet of the injector through the first through hole.

[0007] Further preferably, the throttle ring is press-fitted into the inlet end of the injector through a clamping groove.

[0008] Further preferably, the first through hole is disposed opposite to the outlet of the injector through a preheating channel, the preheating channel is coaxially arranged with the first through hole and the inner diameter of the preheating channel is larger than the aperture of the first through hole.

[0009] Further preferably, a plurality of arc ignition devices are evenly arranged along a circumference with the outlet of the injector as the center, and the outlet of the injector is located on the axis of the combustion chamber housing.

[0010] Further preferably, the target atomization electric ignition monopropellant rocket engine further includes a heat insulation plate, and the solenoid valve, the heat insulation plate and the injector are connected in series through a flange in sequence.

[0011] Further preferably, the arc ignition device is an arc thruster, and the direction of the high-temperature plume generated by the arc thruster is arranged corresponding to the outlet of the combustion chamber housing.

[0012] Further preferably, the combustion chamber housing is a tapered structure, the target surface structure is located on the axis of the combustion chamber housing, a plug cone is fixedly connected to the rear end of the target surface structure, and the profile surface of the plug cone and the inner wall surface of the combustion chamber housing form a plug nozzle structure.

[0013] Further preferably, when the arc thruster works and the solenoid valve is opened, the chamber pressure of the arc thruster is not lower than the chamber pressure in the combustion chamber housing.

[0014] Further preferably, the arc ignition device is an arc igniter.

[0015] The beneficial effects of the target atomization electric ignition monopropellant rocket engine provided by the present invention are as follows:

[0016] 1. High working stability: The tiny droplets generated by atomization through the target surface structure are evenly distributed circumferentially, the energy of the generated flame front is more uniform, and the working stability of the engine is higher;

[0017] 2. High combustion efficiency: The catalytic bed structure is cancelled, and under the same envelope size, the volume of the combustion chamber is larger, the residence time of the fuel gas in the combustion chamber is increased, which is beneficial to the full combustion of the propellant and improves the combustion efficiency;

[0018] 3. Fast on-off response speed: Compared with the catalytic ignition monopropellant engine, in the atomization process of starting up of the present invention, there are no complex processes such as propellant filling and heating the catalytic bed, and the response time is significantly shortened. In the shutdown process, after the propellant is cut off by the solenoid valve, the propellant in the combustion chamber can be discharged from the engine in a short time, and the response speed is fast;

[0019] 4. Adaptable to multiple propellants: The catalytic ignition monopropellant engine needs to use a catalyst that matches the type and working characteristics of the propellant. The present invention uses a target atomization followed by electric ignition method or a high-temperature wall ignition method to ignite the atomized propellant. It only needs to adjust the temperature of the combustion chamber wall to reach the corresponding ignition temperature of the propellant to continuously work. One structure can meet the application needs of multiple propellants;

[0020] 5. Short development cycle and low cost: The present invention eliminates the catalytic bed structure and uses a target atomization injector, significantly reducing the number of components, which is beneficial to reducing the development cost and shortening the development cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention will be further described in detail below in conjunction with the drawings and embodiments:

[0022] Figure 1 is a perspective view of the target atomization electric ignition monopropellant rocket engine provided by the present invention;

[0023] Figure 2 is Figure 1 a sectional view of

[0024] Figure 3 is a sectional view of the injector;

[0025] Figure 4 is a schematic diagram of the electric propulsion working mode of the engine when the arc ignition device is an arc thruster;

[0026] Figure 5 is a schematic diagram of the target atomization electric ignition propulsion working mode of the engine when the arc ignition device is an arc thruster;

[0027] Figure 6 is a schematic diagram of the chemical propulsion working mode of the engine when the arc ignition device is an arc igniter. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] The present invention will be further explained below in conjunction with specific implementation schemes, but the present invention is not limited thereto.

[0029] To solve the problems of the traditional catalytic ignition monopropellant rocket engine, such as complex structure, poor combustion stability, slow on-off response speed, and dedicated catalytic bed for propellants, as Figure 1 、 Figure 2As shown in the figure, the present invention provides a target atomization electric ignition monopropellant rocket engine, comprising: an injector 1, an arc ignition device 2 and a combustion chamber housing 3. Among them, the inlet of the injector 1 is connected to a propellant tank through a solenoid valve 4, and a monopropellant is stored in the propellant tank, such as HAN-based, ADN-based, NOFBX, etc. A target surface structure 11 is correspondingly and spacedly arranged at the outlet position of the injector 1, which is used to atomize the high-speed propellant jet ejected from the outlet of the injector 1 and impinging on the target surface structure 11 into tiny droplets. The arc ignition device 2 is fixedly connected to the injector 1, the combustion chamber housing 3 is fixedly connected to the outlet end of the injector 1, and the outlet of the injector 1 and the outlet of the arc ignition device 2 are both communicated with the inside of the combustion chamber housing 3.

[0030] For this target atomization electric ignition monopropellant rocket engine, the target surface structure can receive the high-speed jet ejected from the outlet of the injector, and utilize the kinetic energy of the high-speed jet to atomize the propellant into tiny droplets. The arc ignition device can heat and ignite the tiny droplets to generate high-temperature and high-pressure gas, thereby generating thrust.

[0031] As an improvement of the technical solution, as Figure 2 shown, a throttle ring 5 is installed at the inlet end of the injector 1. A first through hole is provided in the middle of the throttle ring 5, and the outlet of the solenoid valve 4 is communicated with the outlet of the injector 1 through the first through hole. The throttle ring is used to turn the propellant into a high-speed jet. Preferably, as Figure 3 shown, the throttle ring 5 is installed at the inlet end of the injector 1 by interference fit through a clamping groove 12. Among them, the aperture of the first through hole must be designed to ensure that the jet velocity of the propellant reaches 35 m / s to 45 m / s. The purpose is to ensure that the target surface structure can atomize the propellant into tiny droplets in the range of 50 μm to 200 μm, so as to improve the combustion efficiency. If a gel propellant with higher viscosity is selected, the jet velocity must be further increased to meet the particle size requirements of the tiny droplets. The specific jet velocity range can be designed according to the physical properties of the monopropellant.

[0032] As an improvement of the technical solution, as Figure 3 shown, the first through hole is arranged opposite to the outlet of the injector 1 through a preheating channel 13. The preheating channel 13 is coaxially arranged with the first through hole and the inner diameter of the preheating channel 13 is larger than the aperture of the first through hole. Through the above design, when the engine is working, part of the gas can flow back from the combustion chamber into the preheating channel, thereby heating the propellant ejected from the first through hole and realizing the preheating of the propellant. At this time, the propellant jet flows in the preheating channel in a wall-free manner. Preferably, as Figure 3As shown, the injector 1 can be a plate-cylinder structure, that is, it is formed by concentrically connecting a circular plate with a circular hole drilled at the center and a cylinder. The card slot 12 is arranged at the free end of the cylinder, and its inner diameter is larger than the aperture of the first through hole in the middle of the throttle ring. The target surface structure 11 is correspondingly arranged at the outlet of the injector 1.

[0033] As an improvement of the technical solution, a plurality of arc ignition devices 2 are evenly arranged along a circumference with the outlet of the injector 1 as the center, and the outlet of the injector 1 is located on the axis of the combustion chamber housing 3. As Figure 3 shown, fixing holes 14 for fixedly installing the arc ignition device 2 are evenly arranged on the injector.

[0034] As an improvement of the technical solution, as Figure 1 、 Figure 2 shown, this target-type atomizing electric ignition single-component rocket engine further includes a heat insulation plate 6, and the solenoid valve 4, the heat insulation plate 6 and the injector 1 are sequentially connected in series through flanges.

[0035] As an improvement of the technical solution, as Figure 4 、 Figure 5 shown, the arc ignition device 2 is an arc thruster. The arc thruster is used to generate a high-temperature plume, which can heat and ignite the tiny droplets formed by the propellant passing through the target surface structure, and then generate high-temperature and high-pressure gas, and generate thrust through the nozzle. To avoid ablation of the engine structure, preferably, the direction of the high-temperature plume generated by the arc thruster is arranged corresponding to the outlet of the combustion chamber housing 3; the arc thruster can be a gas-working medium arc thruster or a gas-working medium micro-cathode arc thruster. Among them, the working medium used in the arc thruster comes from the high-pressure gas in the system gas cylinder or the gas generator, such as: helium, ammonia, nitrogen, hydrogen mixture, etc.

[0036] When the arc ignition device 2 is an arc thruster, there are three working modes of the engine, which are specifically as follows:

[0037] Electric propulsion working mode: As Figure 4 shown, a high-temperature plume 21 is generated through the arc thruster to generate thrust;

[0038] Electric-chemical hybrid propulsion working mode: As Figure 5 shown, first, a high-temperature plume is generated through the arc thruster. Then, the solenoid valve is opened, and the single-component propellant is pushed by the supply pressure and becomes a high-speed jet at the outlet of the injector and impacts on the target surface structure to form a large number of tiny droplets 8. The above-mentioned tiny droplets are heated and ignited by the high-temperature plume to continuously generate high-temperature and high-pressure gas. The high-temperature plume and the gas generated by the combustion of the single-component propellant are jointly ejected through the nozzle to generate thrust; in this state, if it is necessary to switch to the electric propulsion working mode, only the solenoid valve needs to be closed to cut off the supply of the single-component propellant;

[0039] Chemical propulsion working mode: The high-temperature plume generated by the arc thruster is used to ignite the monopropellant (tiny droplets). After the temperature of the combustion chamber wall reaches the propellant pyrolysis temperature, the arc thruster is turned off and the engine is switched to the chemical propulsion working mode. At this time, the tiny droplets generated by atomization will undergo thermal decomposition when they hit the inner wall of the combustion chamber, producing high-temperature and high-pressure combustion gas, thereby achieving self-sustaining operation.

[0040] As an improvement of the technical solution, Figure 4 , Figure 5 As shown, the combustion chamber shell 3 is a tapered structure, the target surface structure 11 is located on the axis of the combustion chamber shell 3, and the rear end of the target surface structure 11 is fixedly connected to a plug cone 7. The profile of the plug cone 7 and the inner wall surface of the combustion chamber shell 3 form a plug nozzle structure. This design allows the combustion chamber to have a nozzle function, so that the high-temperature and high-pressure airflow is converted into a supersonic airflow and generates thrust, and there is no need to install a nozzle.

[0041] As an improvement to the technical solution, when the arc thruster is working and the solenoid valve 4 is opened, the chamber pressure of the arc thruster needs to be no lower than the chamber pressure in the combustion chamber shell 3, and the arc plume of the arc thruster can be in a subsonic flow state, which can ignite the monopropellant.

[0042] As an improvement of the technical solution, Figure 6 As shown, the arc ignition device 2 is an arc igniter. At this time, the engine can only work in the chemical propulsion working state, wherein the arc igniter is used to continuously strike an arc when the temperature of the combustion chamber wall does not reach the propellant pyrolysis temperature, thereby igniting the propellant.

[0043] As an improvement of the technical solution, when the arc ignition device 2 is an arc igniter, the rear end of the combustion chamber shell 3 is connected to a nozzle.

[0044] Among them, the side of the target surface structure used to receive the propellant jet can be designed as a plane. As an improvement of the technical solution, the side of the target surface structure used to receive the propellant jet is designed as a convex surface with the convex direction pointing to the throttle ring. The convex surface design can make the trajectory of the tiny droplets formed after the propellant is atomized into an umbrella shape, thereby making the contact point between the atomized tiny droplets and the wall of the combustion chamber shell closer to the throat. Because the throat is the position with the highest heat flux density among all parts of the engine, the umbrella-shaped atomization surface is conducive to igniting the propellant on the one hand, and on the other hand, the evaporation heat absorption of the propellant can reduce the throat temperature, reduce the heat transfer from the throat to the injector, and improve reliability.

[0045] The detailed description of the present invention is written in a progressive manner, emphasizing the differences between the various implementations, and similar parts thereof can be referred to each other.

[0046] The embodiments of the present invention have been described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present invention within the scope of knowledge possessed by those of ordinary skill in the art.

Claims

1. A target-type atomizing electric ignition monopropellant rocket engine, characterized in that: include: An injector (1), an arc ignition device (2) and a combustion chamber shell (3), wherein the inlet of the injector (1) is connected to a propellant tank via a solenoid valve (4), a target surface structure (11) is arranged at a position corresponding to and spaced from the outlet of the injector (1), the target surface structure (11) being used to atomize a high-speed propellant jet ejected from the outlet of the injector (1) and impacting the target surface structure (11) into tiny droplets, the arc ignition device (2) being fixedly connected to the injector (1), the combustion chamber shell (3) being fixedly connected to the outlet end of the injector (1), the outlet of the injector (1) and the outlet of the arc ignition device (2) both being connected to the inside of the combustion chamber shell (3).

2. The target-type atomizing electric ignition monopropellant rocket engine according to claim 1, characterized in that: A throttle ring (5) is installed at the inlet end of the injector (1), a first through hole is provided in the middle of the throttle ring (5), and the outlet of the solenoid valve (4) is connected to the outlet of the injector (1) through the first through hole.

3. The target-type atomizing electric ignition monopropellant rocket engine according to claim 2, characterized in that: The throttle ring (5) is interference-fittedly mounted on the inlet end of the injector (1) through a clamping groove (12).

4. The target-type atomizing electric ignition monopropellant rocket engine according to claim 2, characterized in that: The first through hole is arranged opposite to the outlet of the injector (1) via a preheating channel (13); the preheating channel (13) is coaxially arranged with the first through hole and the inner diameter of the preheating channel (13) is larger than the aperture of the first through hole.

5. The target-type atomizing electric ignition monopropellant rocket engine according to claim 1, characterized in that: The arc ignition devices (2) are multiple and are evenly arranged along a circumference with the outlet of the injector (1) as the center, and the outlet of the injector (1) is located on the axis of the combustion chamber shell (3).

6. The target-type atomizing electric ignition monopropellant rocket engine according to claim 1, characterized in that: The target-type atomizing electric ignition monopropellant rocket engine also includes a heat shield (6), and the solenoid valve (4), the heat shield (6) and the injector (1) are sequentially connected in series via a flange.

7. The target-type atomizing electric ignition monopropellant rocket engine according to claim 1, characterized in that: The arc ignition device (2) is an arc thruster, and the direction of the high-temperature plume generated by the arc thruster is arranged corresponding to the outlet of the combustion chamber shell (3).

8. The target-type atomizing electric ignition monopropellant rocket engine according to claim 1, characterized in that: The combustion chamber shell (3) is a tapered structure, the target surface structure (11) is located on the axis of the combustion chamber shell (3), the rear end of the target surface structure (11) is fixedly connected to a plug cone (7), and the profile of the plug cone (7) and the inner wall surface of the combustion chamber shell (3) form a plug nozzle structure.

9. The target-type atomizing electric ignition monopropellant rocket engine according to claim 7, characterized in that: When the arc thruster is operating and the electromagnetic valve (4) is open, the chamber pressure of the arc thruster is not lower than the chamber pressure in the combustion chamber casing (3).

10. The target-type atomizing electric ignition monopropellant rocket engine according to claim 1, characterized in that: The arc ignition device (2) is an arc igniter.

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