Pulse detonation attitude control engine system

Abstract

The invention discloses a pulse detonation attitude control engine system which comprises an ignition detonation straight pipe and at least one S-shaped attitude control pipe. The ignition detonating straight pipe comprises an ignition section and an obstacle detonating section which are sequentially arranged in the axial direction; wherein an explosion promotion barrier is arranged in the barrier explosion initiation section; each S-shaped attitude control tube comprises a branch tube and two bent push tubes; the center of the branch pipe is vertically arranged at the tail end of the obstacle detonating section and is communicated with the obstacle detonating section through a valve; the two bent push pipes are symmetrically arranged relative to the center of the branch pipe to form an S shape; each bent push pipe comprises a bent pipe section and an exhaust nozzle section, and the two ends of each bent pipe section are connected with the corresponding branch pipe and the corresponding exhaust nozzle section respectively. According to the invention, the advantages of high-efficiency combustion and high-precision adjustable pulse thrust of the pulse detonation engine can be played as far as possible while the microminiaturization of the attitude control engine is met, the thermodynamic cycle theory can be improved by more than 20% compared with common chemical propulsion, and the on-orbit life of a spacecraft is effectively prolonged.

Description

Technical Field

[0001] The present invention relates to the field of attitude control engines, and in particular to a pulsed detonation attitude control engine system. Background Art

[0002] Combustion, as the energy conversion process of chemical propellants, its efficiency has an important impact on the performance of engines. Combustion waves in nature can be divided into two types: deflagration waves and detonation waves. Deflagration waves are approximately isobaric combustion, which is the approximate thermodynamic cycle process of all current gas turbines; while detonation waves are approximately isochoric combustion, and its theoretical thermodynamic cycle efficiency is 20% higher than that of isobaric combustion. Therefore, a power device based on the detonation thermodynamic cycle - the detonation engine has potential advantages such as high thermal efficiency and simple structure, which can greatly reduce the fuel consumption rate of the propulsion system. By applying detonation combustion to the energy conversion process of the propulsion system, detonation engines have been developed. Related research mainly focuses on: pulsed detonation engines, rotating detonation engines, stationary detonation engines, etc. However, the application research of detonation combustion in the field of space propulsion is still less.

[0003] After certain developments in the ability to enter space, the in-orbit residence ability and the space propulsion ability required for space activities have successively become the research hotspots of various countries. Space propulsion technology has made great strides in both conventional propulsion and new propulsion technologies. Currently, the representative of conventional propulsion: chemical propulsion is still the first choice for various space missions, and its performance is constantly being optimized. Electric propulsion, led by technologies such as Hall and ion electric propulsion, has achieved a large number of successful applications in fields such as satellites. In recent years, the micro-thrust field has developed towards low power consumption and small mass driven by the large demand for small satellites.

[0004] Among them, the principle of chemical propulsion is simple, with high reliability and low cost, and it is still the current mainstream attitude control engine mode, but there will be disadvantages such as the overweight of the engine system and low performance. Some chemical propulsion modes also have problems such as large toxicity of the propellant and overly complex systems.

[0005] Although the electric propulsion system has a high specific impulse and consumes less working medium, it is limited by the electric power allocated to the propulsion system by the spacecraft, and the thrust is usually very small, generally in the order of μN - mN. And due to its complex system structure, the electric propulsion system is generally extremely expensive.

[0006] The main requirements of the attitude control engine system are pulsed working ability, small pulse width, precise control, etc. And the pulsed detonation rocket engine exactly meets the ability requirements of the attitude control engine. Considering the advantages and disadvantages of the two existing propulsion technologies mentioned above, the best research direction for the current attitude control engine is pulsed detonation attitude control.

[0007] Among them, chemical propulsion has a simple principle, high reliability and low cost, and is still the current mainstream attitude control engine mode. However, it has disadvantages such as the engine system being too heavy and the performance being too low. Some chemical propulsion modes also have problems such as high propellant toxicity and overly complex systems. Summary of the invention

[0008] The technical problem to be solved by the present invention is to provide a pulse detonation attitude control engine system in view of the deficiencies of the above-mentioned prior art. The thermal cycle of the pulse detonation attitude control engine system can be improved by more than 20% compared with the traditional chemical propulsion system, the structural weight of the attitude control unit is significantly reduced, the on-orbit life of the spacecraft is effectively extended, and the fuel adopts a non-toxic propellant combination of hydrogen / oxygen.

[0009] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0010] A pulse detonation attitude control engine system comprises an ignition and detonation straight tube and at least one S-shaped attitude control tube.

[0011] The ignition and detonation straight tube comprises an ignition section and an obstacle detonation section which are arranged in sequence along the axial direction; wherein an explosion-promoting obstacle is built into the obstacle detonation section.

[0012] Each S-shaped attitude control pipe includes a branch pipe and two curved push pipes.

[0013] The center of the branch pipe is vertically arranged at the tail end of the obstacle detonation section and is connected through a valve.

[0014] The two curved push pipes are arranged symmetrically about the center of the branch pipe to form an S shape; each curved push pipe includes a curved pipe section and a tail nozzle section, and the two ends of the curved pipe section are respectively connected to the branch pipe and the tail nozzle section.

[0015] The S-shaped attitude control tubes have two branches, which are perpendicular to each other, and the planes where the two branches are located are perpendicular to the ignition and detonation straight tubes.

[0016] There are three S-shaped attitude control tubes, and the planes where the three branch tubes of the three S-shaped attitude control tubes are located are perpendicular to the ignition and detonation straight tubes; the three S-shaped attitude control tubes all have six curved push tubes, and the directions of the tail nozzle sections in two adjacent curved push tubes are perpendicular to each other.

[0017] The inner diameters of the ignition section, obstacle detonation section, branch pipe and curved pipe section are equal, and the tail nozzle section is an expansion pipe.

[0018] The inner diameters of the ignition section, obstacle detonation section, branch pipe and curved pipe section are all 10 mm, and the contraction ratio of the tail nozzle section is 34.2.

[0019] The curved pipe section is a quarter - radian bent pipe with a curvature radius of 40 mm for the curved pipe section. Half of the length of the branch pipe forms the momentum arm, so the length of the momentum arm is 172 mm.

[0020] The propellants used in the ignition section are hydrogen and oxygen.

[0021] Hydrogen, as the fuel, is supplied to the ignition section through a hole with a diameter of 2 mm; the oxidizer is supplied to the ignition section through a pipe with an inner diameter of 6.9 mm.

[0022] The explosion - promoting obstacle is an M10 threaded obstacle.

[0023] A low - frequency pressure sensor is set at the propellant inlet of the ignition section, and a high - frequency pressure sensor is set at the end of the obstacle detonation section.

[0024] The present invention has the following beneficial effects:

[0025] 1. The present invention conforms to the attitude control application prospect of the pulse detonation engine. It uses non - toxic and storable hydrogen / oxygen as fuel, meets the development direction of miniaturization of attitude control engines, and gives full play to the advantages of high - efficiency combustion and high - precision adjustable pulse thrust of the pulse detonation engine as much as possible.

[0026] 2. Compared with traditional chemical propulsion and electric propulsion, the pulse detonation attitude control engine of the present invention has the advantages of high specific impulse, variable thrust, reliable system and long service life in the field of attitude control.

[0027] 3. The S - type 6 - tube design involved in the present invention can increase the torque and improve the force - transmission efficiency. By sharing the detonation section of the attitude control engines in three directions, the structural complexity is reduced, and the attitude - control pulse - width modulation of the spacecraft can be realized only by precisely controlling the valves. Brief Description of the Drawings

[0028] Figure 1 It is a three - dimensional model schematic diagram of a pulse detonation attitude control engine system provided by an embodiment of the present invention.

[0029] Figure 2 It is a two - dimensional model schematic diagram of a pulse detonation attitude control engine system provided by an embodiment of the present invention.

[0030] Figure 3 It is a sectional view of a pulse detonation attitude control engine system provided by an embodiment of the present invention.

[0031] Figure 4 It is a three - dimensional view of the six - degree - of - freedom layout of a pulse detonation attitude control engine system provided by an embodiment of the present invention.

[0032] Figure 5 It is a perspective view of the layout of the attitude control engine group of a cuboid satellite with a six - degree - of - freedom layout according to the present invention.

[0033] Figure 6 This is a perspective view of the layout of a six-degree-of-freedom cylindrical satellite attitude control engine group according to the present invention.

[0034] Among them are:

[0035] 10. Ignition and detonation straight pipe; 11. Ignition section; 12. Obstacle detonation section;

[0036] 20. S-shaped attitude control pipe;

[0037] 21. Branch pipe;

[0038] 22. Bent thrust pipe; 221. Curved pipe section; 222. Tail nozzle section. Specific implementation manner

[0039] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific preferred implementation manners.

[0040] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by terms such as "left side", "right side", "upper part", "lower part", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. "First", "second", etc. do not represent the importance of components, so they cannot be understood as limitations to the present invention. The specific dimensions adopted in this embodiment are only for illustrating the technical solution by way of example and do not limit the protection scope of the present invention.

[0041] As Figures 1 to 4 shown, a pulse detonation attitude control engine system includes an ignition and detonation straight pipe 10 and at least one S-shaped attitude control pipe 20. Among them, the number of S-shaped attitude control pipes is set according to the attitude control degrees of freedom to be controlled. In this Figures 1 to 3 embodiment, one S-shaped attitude control pipe is provided, having two degrees of freedom in direction; in this Figures 4 to 6 embodiment, three S-shaped attitude control pipes are provided, thus having six degrees of freedom in direction.

[0042] The ignition and detonation straight pipe includes an ignition section 11 and an obstacle detonation section 12 arranged in sequence along the axial direction.

[0043] The length of the above-mentioned ignition section is preferably 20 mm, the length of the obstacle detonation section is preferably 190 mm, and it is internally provided with an explosion-promoting obstacle, preferably an M10 threaded obstacle.

[0044] Furthermore, the inner diameters of the ignition section and the detonation section are preferably equal, preferably both 10 mm.

[0045] The propellant used in the ignition section is preferably hydrogen and oxygen. Among them, hydrogen is used as the fuel and is supplied to the ignition section through a hole with a diameter of 2 mm; the oxidizer is supplied to the ignition section through a pipe with an inner diameter of 6.9 mm.

[0046] The successful detonation of the detonation wave is the key to the efficient operation of the detonation engine. The energy required for the direct detonation of conventional hydrocarbon fuels is about 10 5 ~10 6 J, which is not easy to achieve. Therefore, at present, detonation engines often adopt an indirect detonation method, that is, through the form of deflagration-to-detonation transition, that is, a lower ignition energy is used to generate a deflagration wave, and the transition process is realized through flame acceleration to generate a detonation wave. The detonation enhancement device is an auxiliary device for accelerating the deflagration-to-detonation transition process. Without relying on the detonation enhancement device, it takes a long distance to complete this transition process in a smooth straight pipe, which may lead to detonation failure. In a limited space, a longer transition distance means a larger propulsion system size, thus limiting the usable space of the payload. In order to shorten the distance and time of the deflagration-to-detonation transition, certain means need to be taken, including placing obstacles in the pipe, that is, the detonation enhancement device. The present invention uses an M10 threaded obstacle to promote detonation.

[0047] Furthermore, a low-frequency pressure sensor is arranged upstream of the propellant inlet in the ignition section, and the measured pressure value is used to determine the total mass flow rate and equivalence ratio of the propellant; a high-frequency pressure sensor is arranged at the end of the obstacle detonation section to confirm whether detonation occurs.

[0048] Each S-shaped attitude control pipe includes a branch pipe 21 and two bent propulsion pipes 22.

[0049] The center of the branch pipe is vertically arranged at the end of the obstacle detonation section and is connected through a valve.

[0050] The two bent propulsion pipes are symmetrically arranged about the center of the branch pipe to form an S shape.

[0051] A. When there are two S-shaped attitude control pipes, the two branch pipes of the two S-shaped attitude control pipes are perpendicular to each other, and the planes where the two branch pipes are located are perpendicular to the ignition detonation straight pipe.

[0052] B. When there are three S-shaped attitude control pipes, the planes where the three branch pipes of the three S-shaped attitude control pipes are located are perpendicular to the ignition detonation straight pipe; each of the three S-shaped attitude control pipes has six bent propulsion pipes, and the orientations of the tail nozzle sections in two adjacent bent propulsion pipes are perpendicular to each other.

[0053] Each bent propulsion pipe includes a curved pipe section 221 and a tail nozzle section 222. The two ends of the curved pipe section are respectively connected to the branch pipe and the tail nozzle section.

[0054] The above-mentioned branch pipe is a straight pipe, and half of its length forms a momentum arm, and the length of the momentum arm is 172 mm.

[0055] The above-mentioned curved pipe section is preferably a quarter-radian bent pipe, and its curvature radius is preferably 40 mm. Further, the inner diameters of the curved pipe section, the branch section, and the ignition and detonation straight pipe are equal, and are all preferably 10 mm.

[0056] The above-mentioned tail nozzle section is a divergent nozzle, and the contraction ratio of the tail nozzle section is preferably 34.2.

[0057] Due to the volume limitation of the satellite, there are also requirements for the axial dimension of the detonation tube. Considering the distance limitation for the transition from deflagration to detonation, a curved tube detonation tube can be used instead of the traditional straight tube. The curved pipe configuration can efficiently utilize space, and this solution becomes a solution direction for the limited space problem in traditional detonation research. Therefore, the present invention selects a curved tube as part of the detonation combustion chamber, which not only ensures the requirement for forming a steering moment but also can further accelerate the detonation and reduce the axial length of the detonation engine. The existence of the branch reduces the magnitude of the outlet pressure of a single detonation tube. Considering the actual application efficiency, a tail nozzle is added at the outlet to further expand the high-pressure exhaust gas to increase the thrust.

[0058] The pulse detonation attitude control engine system provided by the embodiment of the present invention maintains the pressures of fuel and oxygen through the installed nozzle throat, and generates thrust by accelerating and discharging the high-pressure gas at the two shunt nozzles.

[0059] Since the present invention ignores the filling process of the combustible mixture, the working process of the pulse detonation attitude control engine designed by the present invention is as Figure 5 divided into the following processes:

[0060] (1) Ignition: High-temperature and high-pressure areas are used for ignition in the ignition section at the head of the detonation chamber.

[0061] (2) Initiation of the detonation wave and the detonation combustion process in the straight pipe: The ignited mixed gas initially forms a low-speed deflagration wave, which interacts with the combustion compression wave formed by reflection at the obstacle initiation section to form a stable detonation wave.

[0062] (3) Diffraction and reflection process of the detonation wave entering the branch section: The plane detonation wave just enters the free space of the branch section and turns into a spherical detonation wave. The forward-propagating wavefront reaches the wall surface of the branch section and then interacts with the diverging wavefront after reflection, and finally tends to be stable to complete the turning.

[0063] (4) Re-acceleration process of the detonation wave in the branch pipe: The detonation wave continues to accelerate in the straight pipe.

[0064] (5) Propagation process of the detonation wave in the curved pipe: The detonation wave is diffracted by the inner wall surface and reflected by the outer wall surface, resulting in attenuation.

[0065] (6) Acceleration and ejection process of the combustion products through the nozzle.

[0066] The above process is repeated in a loop.

[0067] In space missions, the attitude adjustment of spacecraft is achieved by the on-off response of attitude control engines. The layout of attitude control engine groups will consider different numbers and layout methods according to different missions. A single attitude control engine group generally consists of four to eight engines, which are installed centrally or dispersedly, and there are two different installation angles, namely "horizontal and vertical" or "tilted". The four-attitude control engine is the smallest layout to achieve three-channel controllability, but it has defects in anti-interference performance and has currently stopped development. The six- and eight-attitude control engine layout forms have improved in stability, but have caused difficulties in the design of fuel transportation pipelines, etc. Due to the existence of three groups of contradictions in the engine layout, namely rapidity and control accuracy, stability and anti-interference ability, cost and control effect, etc., it is relatively complex and many factors need to be considered. Therefore, the present invention designs a six-attitude control engine group layout with a shared intake duct and detonation section, and configures two engines providing torques in opposite directions in each control channel, and combines the control of three S-type detonation engines into a group sharing a single detonation section to simplify the structure as Figure 4 shown. Among them, the opening and closing of the pipeline are controlled by a solenoid valve arranged inside the pipe to cooperate with the control signal. The solenoid valve can be a single variable three-channel solenoid valve installed at the center of the branch, allowing only one path to generate a detonation wave, or solenoid valves can be installed at each channel, that is, six solenoid valves are installed on the same side.

[0068] Furthermore, Figure 5 is a perspective view of the attitude control engine group layout of a cuboid satellite with a six-degree-of-freedom layout according to the present invention; Figure 6 is a perspective view of the attitude control engine group layout of a cylindrical satellite with a six-degree-of-freedom layout according to the present invention.

[0069] The pulse detonation attitude control engine system in the present invention, while meeting the miniaturization of attitude control engines, gives full play to the advantages of high-efficiency combustion and high-precision adjustable pulse thrust of pulse detonation engines as much as possible. The thermal cycle can theoretically increase by more than 20% compared with ordinary chemical propulsion, effectively extending the in-orbit life of spacecraft.

[0070] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention, and these equivalent transformations all belong to the protection scope of the present invention.

Claims

1. A pulse detonation attitude control engine system, characterized in that: It includes an ignition and initiation straight tube and at least one S-shaped attitude control tube; the ignition and initiation straight tube includes an ignition section and an obstacle initiation section arranged in sequence along the axial direction; wherein, an explosion-promoting obstacle is built in the obstacle initiation section. Each S-shaped attitude control tube includes a branch tube and two bending push tubes. The center of the branch tube is vertically arranged at the tail end of the obstacle initiation section and is connected through a valve. The two bending push tubes are symmetrically arranged about the center of the branch tube to form an S shape; each bending push tube includes a curved tube section and a tail nozzle section, and the two ends of the curved tube section are respectively connected to the branch tube and the tail nozzle section.

2. The pulse detonation attitude control engine system according to claim 1, characterized in that: There are two S-shaped attitude control tubes, and the two branch tubes of the two S-shaped attitude control tubes are perpendicular to each other, and the plane where the two branch tubes are located is perpendicular to the ignition and initiation straight tube.

3. The pulse detonation attitude control engine system according to claim 1, wherein: There are three S-shaped attitude control tubes, and the plane where the three branch tubes of the three S-shaped attitude control tubes are located is perpendicular to the ignition and initiation straight tube; each of the three S-shaped attitude control tubes has six bending push tubes, and the orientations of the tail nozzle sections of adjacent two bending push tubes are perpendicular to each other.

4. The pulse detonation attitude control engine system according to claim 1, characterized in that: The inner diameters of the ignition section, the obstacle initiation section, the branch tube and the curved tube section are equal, and the tail nozzle section is an expansion tube.

5. The pulse detonation attitude control engine system according to claim 4, wherein: The inner diameters of the ignition section, the obstacle initiation section, the branch tube and the curved tube section are all 10 mm, and the contraction ratio of the tail nozzle section is 34.

2.

6. The pulse detonation attitude control engine system according to claim 5, characterized in that: The curved tube section is a quarter-radian bending tube, the curvature radius of the curved tube section is 40 mm, and half of the length of the branch tube forms a momentum arm, and the length of the momentum arm is 172 mm.

7. The pulse detonation attitude control engine system according to claim 4, characterized in that: The propellant used in the ignition section is hydrogen and oxygen.

8. The pulse detonation attitude control engine system according to claim 7, wherein: Hydrogen is used as fuel and is supplied to the ignition section through a hole with a diameter of 2 mm; the oxidant is supplied to the ignition section through a pipeline with an inner diameter of 6.9 mm.

9. The pulse detonation attitude control engine system according to claim 4, characterized in that: The explosion-promoting obstacle is an M10 thread obstacle.

10. The pulse detonation attitude control engine system according to claim 1, wherein: A low-frequency pressure sensor is arranged at the propellant inlet of the ignition section, and a high-frequency pressure sensor is arranged at the tail end of the obstacle initiation section.

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