A bipropellant thrust attitude control engine

Abstract

This invention discloses a dual-component thrust attitude control engine, comprising a mounting plate, a swirling mixer, an igniter, and a combustion chamber nozzle. The mounting plate contains two isolated gas chambers, each with an intake pipe connected to its inlet and an on / off controllable solenoid valve at its outlet. The two inlets of the swirling mixture are connected to the outlets of the two gas chambers, and the outlet of the swirling mixer is connected to the inlet of the combustion chamber nozzle. The swirling mixer is used to swirl and mix the gas input into it before outputting it. The igniter is used to ignite the mixed gas input into the combustion chamber nozzle. The combustion chamber nozzle is used to supply the combusted mixed gas for combustion output. This configuration solves the problem that existing technologies cannot simultaneously achieve compact structure, high mixing efficiency, and excellent thermal management performance.

Description

Technical Field

[0001] This invention relates to the technical field of engines, and particularly to a dual-component thrust attitude control engine. Background Technology

[0002] With the rapid development of small satellite and micro / nano satellite technologies, higher demands are being placed on attitude control and orbital maneuverability during satellite operation. As a key actuator in the satellite attitude control system, the low-thrust attitude control engine needs to simultaneously meet the requirements of small size, light weight, fast response, and high reliability.

[0003] In existing low-thrust chemical propulsion systems, hydrazine propellants such as hydrazine, methylhydrazine, and unsymmetrical dimethylhydrazine are typically combined with nitrogen tetroxide to form a binary auto-ignition propulsion system. This system offers advantages such as high specific impulse and reliable ignition, but also suffers from high toxicity, stringent protection requirements, system complexity, and significant structural mass, hindering miniaturization and green technology development. Furthermore, hydrazine propellants exhibit lower specific impulse when used in monopropellant mode and are highly dependent on catalyst bed life and temperature control systems.

[0004] With the continuous development of research on single / bicomponent propellants, nitrous oxide has gradually become a new type of green oxidant due to its advantages such as mild storage conditions, low cost, and good availability. In addition, compared with traditional fuels, ammonia has the characteristics of high energy density and easy storage and transportation when used as fuel.

[0005] Therefore, the rational combination of nitrous oxide and ammonia to construct a novel green single / dual-component propulsion system is expected to effectively solve the toxicity and miniaturization bottlenecks of traditional hydrazine propellants. At the same time, it takes into account the requirements of high specific impulse, high reliability, greenness, and lightweight of the propulsion system, providing a new technical path for the development trend of small-thrust attitude control engines to adapt to small satellites and micro / nano satellites. It also lays a solid propulsion technology foundation for improving the on-orbit attitude control and orbital maneuverability of satellites, and promotes the iterative upgrade of small satellite propulsion systems towards a safer, more efficient, and more environmentally friendly direction.

[0006] Patent content related to this invention US Patent 2009007541A1 discloses a space thruster using nitrous oxide as its core propellant. In its bi-component mode, it uses a rhodium-based catalyst to decompose N₂O, generating high-temperature gas that ignites low-toxicity fuels such as ethanol for combustion propulsion. This technology is highly dependent on catalyst activity and extremely sensitive to propellant purity. Even trace impurities or combustion product deposits can lead to catalyst performance degradation, affecting the long-term reliability of the thruster. Furthermore, this scheme employs indirect ignition via catalytic decomposition, requiring a preheating device to maintain the initial catalyst temperature, increasing the complexity of system timing control and increasing the risk of ignition delay or failure in pulsed operation mode. In addition, the lack of effective thermal isolation between the combustion chamber and upstream components allows high-temperature combustion gases to easily affect the operational stability of precision components such as solenoid valves through structural heat conduction, limiting their lifespan under frequent start-stop conditions. Although this thruster has made progress in propellant non-toxicity and cryogenic adaptability, its low system integration and insufficient thermal management capabilities make it difficult to meet the application requirements of highly integrated small satellite attitude control systems.

[0007] Furthermore, domestic patent CN113107710B discloses a low-thrust bicomponent attitude control engine. This patent uses a bicomponent nozzle to achieve propellant impact auto-ignition and precisely controls the flow rate through an independent solenoid valve, achieving a technological breakthrough in the 2 N-class low-thrust field. However, its injection structure follows the impact-type mixing principle of traditional bicomponent engines, facing inherent problems such as excessively short mixing paths and uneven mixing at a miniaturized scale. For the specific propellant combination of nitrous oxide and ammonia, the two have significant differences in physical properties, making it difficult for the traditional impact-type structure to achieve sufficient mixing in a limited space. This can easily lead to localized combustion-rich or oxygen-rich areas in the combustion chamber, causing combustion oscillations and thrust fluctuations. Simultaneously, this design directly installs the solenoid valve upstream of the injector without a buffer gas container structure, meaning that propellant supply pressure fluctuations directly affect the injection pressure drop and mixture ratio stability. High temperatures in the combustion chamber are conducted backwards through the propellant flow channel, easily causing thermal aging of the solenoid valve seals and drift in response characteristics, affecting the engine's control accuracy and long-term reliability.

[0008] In summary, existing low-thrust engines using a combination of nitrous oxide and ammonia still face the following technical challenges: (1) Existing small thrust bicomponent engines usually require independent pressure stabilization and heat insulation structures, which are complex and have large structural mass, making them unsuitable for high-integration applications. (2) Existing injection or mixing structures cannot achieve efficient and stable mixing of nitrous oxide and ammonia in a limited space, resulting in low combustion efficiency and obvious combustion fluctuations; (3) The high temperature generated by the combustion chamber and nozzle can cause thermal shock to the upstream solenoid valve and other components, affecting the reliability and life of the engine.

[0009] Therefore, there is an urgent need for a compact, efficient, and thermally efficient low-thrust dual-element attitude control engine to meet the application requirements of small satellite propulsion systems. Summary of the Invention

[0010] The purpose of this invention is to provide a dual-component thrust attitude control engine to solve the problem that the existing technology cannot simultaneously achieve compact structure, high mixing efficiency, and excellent thermal management performance.

[0011] To address the aforementioned technical problems, this invention provides a dual-component thrust attitude control engine, comprising a mounting plate, a swirling mixer, an igniter, and a combustion chamber nozzle. The mounting plate contains two isolated gas chambers, each with an intake pipe connected to its inlet end and an on / off controllable solenoid valve at its outlet end. The two inlets of the swirling mixture are respectively connected to the outlet ends of the two gas chambers, and the outlet end of the swirling mixer is connected to the inlet end of the combustion chamber nozzle. The swirling mixer is used to swirl and mix the gas input into it before outputting it. The igniter is used to ignite the mixed gas input into the combustion chamber nozzle. The combustion chamber nozzle is used to supply the ignited mixed gas for combustion output.

[0012] In one embodiment, the mounting plate has a hollow structure inside, and a partition plate is provided inside the mounting plate to separate the interior of the mounting plate into two air chambers.

[0013] In one embodiment, the solenoid valve is located outside the air chamber.

[0014] In one embodiment, the mounting plate has a valve chamber on its exterior, and each of the two valve chambers has a ventilation hole, which is connected to the two air chambers respectively. Each of the two air chambers has an air outlet pipe, the inlet of which is arranged within the space surrounded by the two ventilation holes, and the outlet of which is connected to the inlet of the cyclone mixer. The two solenoid valves are respectively connected and sealed to the two valve chambers, the inlet of which is connected to the two ventilation holes respectively, and the outlet of which is connected to the inlet of the two outlet pipes respectively.

[0015] In one embodiment, the solenoid valve is provided with an air guide chamber and a movable controllable blocking rod; the air guide chamber is connected to the air inlet and air outlet of the solenoid valve; the blocking rod has a working state to move into the air outlet of the solenoid valve to block the air outlet of the solenoid valve.

[0016] In one embodiment, the intake pipe and the solenoid valve are both located on the same side of the mounting plate; the swirl mixer, the igniter, and the combustion chamber nozzle are all located on the opposite side of the mounting plate.

[0017] In one embodiment, the air inlet and air outlet of the air chamber are arranged separately from each other, so that the air inlet and air outlet of the air chamber are distributed in different areas inside it.

[0018] In one embodiment, the swirl mixer includes a mixer housing and a swirl forming element; the mixer housing is sealed around the outlet end of the swirl forming element, the inlet end of the mixer housing is connected to the outlet end of one of the gas chambers, the outlet end of the mixer housing is connected to the inlet end of the combustion chamber nozzle, and the igniter is provided on the mixer housing; the inlet end of the swirl forming element is connected to the outlet end of another gas chamber, and the outer peripheral wall of the outlet end of the swirl forming element is provided with a plurality of diverting gas outlet holes, the plurality of diverting gas outlet holes are arranged circumferentially, and a swirl guide plate is provided between adjacent diverting gas outlet holes, the swirl guide plate being used to guide the gas output from the diverting gas outlet holes into a swirl.

[0019] In one embodiment, along the gas delivery direction of the swirl mixer, the location where the guide gas of the mixer housing is introduced into its interior is located before the portion where the guide gas of the swirl forming element is introduced into the interior of the mixer housing.

[0020] In one embodiment, the combustion chamber nozzle includes a first pipe section and a second pipe section that are connected to each other, and the adjacent portions of the first pipe section and the second pipe section are both narrow-diameter structures.

[0021] The beneficial effects of this invention are as follows: 1. Highly integrated structure, small size, and light weight: The gas chamber used to achieve pressure stabilization is integrated inside the mounting plate, eliminating the need for separate gas cylinders, pressure regulating valves, and connecting pipelines in traditional solutions. This significantly reduces the number of parts, making the engine structure more compact and significantly reducing the dry weight of the system. It is particularly suitable for small satellites and micro / nano satellites with stringent constraints on limited space and payload capacity.

[0022] 2. Excellent thermal management performance: The gas chamber inside the mounting plate forms a pre-storage space for propellant flow. During engine operation, the cryogenic propellant continuously flows through the interior of the mounting plate, actively cooling the mounting plate using the sensible heat and latent heat of vaporization of the propellant. This forms a highly efficient thermal buffer barrier between the high-temperature zone of the combustion chamber and the upstream precision solenoid valve, effectively preventing the reverse conduction of combustion heat, protecting components such as the solenoid valve from thermal shock, and improving long-term operational reliability and lifespan.

[0023] 3. High mixing efficiency and combustion stability: The strong shear swirling field generated by the swirling mixer enables rapid and uniform mixing of nitrous oxide and ammonia, two components with large differences in physical properties, in a very small space. This avoids the problems of uneven mixing and easy oscillation in traditional impact mixing at the microscale, thereby improving combustion efficiency and reducing thrust fluctuations.

[0024] 4. By using a partition plate to integrally form the internal cavity of the mounting plate into two independent air chambers, not only is the structure extremely simplified, avoiding the use of external pipelines and independent containers, but more importantly, the partition plate itself, as part of the mounting plate, enhances the structural rigidity and vibration resistance of the mounting plate. At the same time, the flow of propellant is used to convectively cool both sides of the partition plate, ensuring complete physical isolation and temperature control of the two propellants during the pre-storage stage.

[0025] 5. The external mounting design of the solenoid valve makes its disassembly, assembly, and maintenance extremely convenient, without requiring the disassembly of the entire engine block. Simultaneously, the fluid pathway formed by the "valve chamber-vent-exhaust pipe" achieves a compact, deflected flow of gas from the chamber to the valve. This not only utilizes the solid thickness of the mounting plate for the flow channel layout, reducing the need for external piping, but also allows for targeted, efficient localized cooling of the solenoid valve mounting base area as propellant flows through these channels, precisely controlling the solenoid valve's operating temperature.

[0026] 6. The cryogenic fluid control unit (i.e., intake manifold, solenoid valve, and swirling mixer) and the high-temperature combustion unit (i.e., swirling mixer, igniter, and combustion chamber nozzle) are physically isolated on both sides of the mounting plate, creating a clear thermal zoning. This layout avoids direct exposure of the solenoid valve to radiant heat from the combustion chamber, further enhancing thermal protection capabilities. Simultaneously, this layout extends the heat exchange distance of the cryogenic propellant within the mounting plate, thereby more fully utilizing the propellant's coldness to absorb the heat conducted by the mounting plate, achieving superior thermal management.

[0027] 7. By separating the inlet and outlet positions of the gas chamber, the "short-circuit" phenomenon of gas flow within the chamber (i.e., gas flows directly from the inlet to the outlet without fully expanding) is disrupted, forcing the airflow to diffuse and meander within the chamber. This serves two purposes: firstly, it stabilizes and buffers pressure, eliminating pressure pulsations caused by the gas supply pipeline; secondly, it increases the residence time of the gas within the chamber, enhancing heat exchange and ensuring a more stable temperature of the outflowing propellant.

[0028] 8. By limiting one type of propellant (such as ammonia) to radially ejected from a swirling element through circumferentially arranged outlet holes, and forming a strong swirling flow under the action of a swirling guide plate, while another propellant (such as nitrous oxide) is introduced through the mixer shell, the two form a cross-shear mixing in the swirling field, thereby achieving at least the following beneficial effects: Precise and controllable mixing scale: By utilizing micro-sized diversion outlet holes and swirling channels, strong turbulence can be generated on a very small injection end face, breaking through the physical limitation of the mixing scale of traditional impact nozzles being limited by the nozzle diameter.

[0029] Preventing backfire and hot backflow: A high-speed swirling flow of propellant creates a low-pressure zone in the center of the flow channel, while simultaneously forming a protective gas film on the wall surface. This effectively prevents the high-temperature combustion gas from flowing back into the nozzle, protecting the injection panel and upstream components.

[0030] 9. The design of the combustion chamber nozzle's narrowing structure (Laval nozzle throat) defines the core flow channel characteristics for thrust generation. This structure ensures that the high-temperature combustion gas reaches the speed of sound at the throat and achieves supersonic expansion in the expansion section, thereby efficiently converting the thermal and pressure energy of the combustion gas into the kinetic energy of the thruster. Designing the throat dimensions specifically for the thermodynamic properties of the nitrous oxide / ammonia propellant combination optimizes specific impulse performance, enabling high propulsion efficiency even under low thrust conditions. Attached Figure Description

[0031] To more clearly illustrate the technical solution of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of the structure provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the mounting plate structure provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the internal structure of the mounting plate provided in an embodiment of the present invention; Figure 4 This is a cross-sectional view of the mounting plate and solenoid valve in an assembly state provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the assembly state of the mounting plate and the cyclone mixer provided in an embodiment of the present invention; Figure 6 This is a cross-sectional view of the mounting plate and cyclone mixer in an assembly state provided in an embodiment of the present invention; Figure 7 This is a schematic diagram of the swirl forming component structure provided in an embodiment of the present invention.

[0033] The attached figures are labeled as follows: 100. Mounting plate; 110. Air chamber; 120. Partition plate; 130. Valve chamber; 140. Vent hole; 150. Air outlet pipe; 200, swirl mixer; 210, mixer housing; 220, swirl forming element; 221, flow outlet; 222, swirl guide plate; 300. Ignition device; 400. Combustion chamber nozzle; 410. First pipe section; 420. Second pipe section; 500. Intake pipe; 600. Solenoid valve; 610. Air guide chamber; 620. Sealing rod. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0035] This invention provides a dual-component thrust attitude control engine, such as... Figure 1 and Figure 3 As shown, the system includes a mounting plate 100, a swirling mixer 200, an igniter 300, and a combustion chamber nozzle 400. The mounting plate 100 has two isolated gas chambers 110 inside, each with an inlet pipe 500 connected to its inlet end and an on / off controllable solenoid valve 600 at its outlet end. The swirling mixer 200 has two inlets connected to the outlets of the two gas chambers 110, and its outlet is connected to the inlet of the combustion chamber nozzle 400. The swirling mixer 200 is used to swirl and mix the gas input into it before outputting it. The igniter 300 is used to ignite the mixed gas input into the combustion chamber nozzle 400. The combustion chamber nozzle 400 is used to supply the ignited mixed gas for combustion output.

[0036] When the engine is running, nitrous oxide and ammonia, two propellant components from the satellite propellant tank, enter two isolated gas chambers 110 inside the mounting plate 100 through two separate air intake pipes 500. The gas chambers 110 serve as buffer volumes to stabilize and pre-store the propellant, while simultaneously using the flow of propellant to cool the mounting plate 100, forming a thermal buffer barrier.

[0037] When thrust is required, the external control system sends an opening command to the two solenoid valves 600 respectively. The solenoid valves 600 are energized and opened, and the two propellants enter the downstream cyclone mixer 200 from their respective gas chambers 110 through the solenoid valves 600.

[0038] In the swirl mixer 200, one propellant, such as ammonia, forms a high-speed rotating airflow; another propellant, such as nitrous oxide, undergoes cross-shear collisions with the rotating airflow, achieving thorough mixing within a very short distance. The uniformly mixed propellant enters the combustion chamber nozzle 400, where it is ignited by the igniter 300, undergoing a combustion reaction to produce high-temperature, high-pressure combustion gas. The combustion gas flows through the combustion chamber nozzle 400 and is accelerated to supersonic speed before being ejected, thereby generating reaction thrust. When it is necessary to stop the thrust, the solenoid valve 600 is de-energized and closed, cutting off the propellant supply and terminating combustion.

[0039] During the aforementioned operation, the integrated gas chamber 110 inside the mounting plate 100 plays a crucial role in pressure stabilization and thermal management. As the propellant diffuses and its flow velocity decreases upon entering the gas chamber 110, pressure pulsations in the gas supply line are effectively attenuated, ensuring stable propellant pressure entering the swirl mixer 200. This is beneficial for maintaining a stable mixture ratio and combustion conditions. Simultaneously, the cryogenic propellant continuously absorbs heat conducted through the structure from the combustion chamber nozzle 400 as it flows through the mounting plate 100, significantly reducing the temperature rise of the mounting plate 100 and protecting temperature-sensitive components such as the solenoid valve 600 mounted on it.

[0040] like Figure 3 As shown, in this embodiment, the mounting plate 100 is configured with a cavity structure inside, and a partition plate 120 is provided inside the mounting plate 100, which separates the interior of the mounting plate 100 into two air chambers 110.

[0041] The separator 120 and the mounting plate 100 can be manufactured using an integral molding process, eliminating the need for additional welding or sealing procedures and ensuring absolute isolation and airtightness between the gas chambers 110. The thickness of the separator 120 can be designed according to the working pressure difference between the two gas chambers 110 and the overall strength requirements of the mounting plate 100. The separator 120 not only achieves physical isolation between the two propellants but also acts as a reinforcing rib, significantly improving the overall rigidity and vibration resistance of the mounting plate 100.

[0042] like Figure 1 and Figure 3 As shown, in this embodiment, the solenoid valve 600 is located outside the gas chamber 110.

[0043] Placing the solenoid valve 600 outside the gas chamber 110, rather than integrating it inside, facilitates its independent installation, removal, and maintenance. When the solenoid valve 600 needs repair or replacement, the entire engine block does not need to be disassembled; the solenoid valve 600 can simply be removed from the valve mounting cavity 130 on the mounting plate 100, greatly improving engine maintainability. Furthermore, the external placement of the solenoid valve 600 avoids compatibility and safety issues that might arise from the solenoid coil being constantly immersed in the propellant atmosphere.

[0044] like Figures 2 to 4 As shown, in this embodiment, the mounting plate 100 is provided with valve chambers 130 on its exterior. Each valve chamber 130 is provided with a ventilation hole 140, which is connected to two air chambers 110 respectively. Each air chamber 110 is provided with an air outlet pipe 150. The air inlet of each air outlet pipe 150 is arranged in the space surrounded by the two ventilation holes 140 respectively, and the air outlet of each air outlet pipe 150 is connected to the air inlet of the cyclone mixer 200. Each solenoid valve 600 is connected and sealed to the two valve chambers 130 respectively. The air inlet of each solenoid valve 600 is connected to the two ventilation holes 140 respectively, and the air outlet of each solenoid valve 600 is connected to the air inlet of each air outlet pipe 150 respectively.

[0045] Specifically, the valve chamber 130 is a groove structure formed on the surface of the mounting plate 100, and its bottom surface has a vent hole 140, which communicates with the corresponding air chamber 110. The mounting flange of the solenoid valve 600 is fastened to the end face of the valve chamber 130 by screws or bolts, and a sealing gasket or sealing ring can be provided between the two to ensure that the gas does not leak. When the solenoid valve 600 is installed in place, the air inlet of the solenoid valve 600 is aligned and connected with the vent hole 140. The air outlet pipe 150 in the air chamber 110 is a slender pipe, with its air inlet located in the central area of ​​the vent hole 140, and its air outlet extending through the mounting plate 100 to the other side, connecting with the corresponding air inlet of the cyclone mixer 200.

[0046] When the solenoid valve 600 is opened, the propellant enters the solenoid valve 600 from the gas chamber 110 through the vent 140, then enters the outlet pipe 150 through the outlet of the solenoid valve 600, and is finally delivered to the cyclone mixer 200. This flow path design of the gas chamber 110, vent 140, solenoid valve 600, and outlet pipe 150 allows the propellant to effectively convectively cool the solenoid valve 600 mounting base as it flows through the valve chamber 130 region, thus controlling the operating temperature of the solenoid valve 600.

[0047] like Figure 4 As shown, in this embodiment, the solenoid valve 600 is provided with an air guide chamber 610 and a movable and controllable blocking rod 620; the air guide chamber 610 is connected to the air inlet end and the air outlet end of the solenoid valve 600; the blocking rod 620 has a working state of moving into the air outlet end of the solenoid valve 600 to block the air outlet end of the solenoid valve 600.

[0048] The solenoid valve 600 can be either a direct-acting or pilot-operated type. In the direct-acting design, the plugging rod 620 is directly driven by the electromagnetic force generated by the solenoid coil, resulting in a fast response and suitability for low-flow conditions. In the pilot-operated design, the electromagnetic force first drives a small pilot valve core, and then the main valve core, i.e., the plugging rod 620, is driven by the pressure difference of the propellant itself, making it suitable for higher-flow conditions. The front end of the plugging rod 620 is typically equipped with a flexible sealing material such as PTFE or fluororubber to ensure a reliable seal with the outlet valve seat. When the solenoid valve 600 is de-energized, the plugging rod 620 presses against the valve seat under the action of the return spring, cutting off the propellant passage; when the solenoid valve 600 is energized, the electromagnetic force overcomes the spring force and lifts the plugging rod 620, opening the propellant passage.

[0049] like Figure 1 As shown, in this embodiment, the intake pipe 500 and the solenoid valve 600 are both located on the same side of the mounting plate 100; the swirl mixer 200, the igniter 300, and the combustion chamber nozzle 400 are all located on the opposite side of the mounting plate 100.

[0050] This layout, which places the cryogenic fluid control element (intake pipe 500) and solenoid valve 600 on one side of the mounting plate 100, and the high-temperature combustion elements (swirling mixer 200, igniter 300, and combustion chamber nozzle 400) on the other side, achieves clear thermal zoning management. The mounting plate 100 itself acts as a thermal barrier, effectively preventing the high-temperature heat radiation and heat conduction generated by the combustion chamber nozzle 400 from directly affecting the interfaces of the solenoid valve 600 and the intake pipe 500.

[0051] Meanwhile, the propellant enters the gas chamber 110 from one side of the mounting plate 100, flows within the gas chamber 110, and is output to the swirl mixer 200 from the other side, effectively absorbing the heat from the mounting plate 100 and providing active cooling. This layout also facilitates the compact installation of the engine on the satellite deck. The intake pipe 500 and solenoid valve 600 face inwards towards the satellite for easy piping connection and maintenance, while the combustion chamber nozzle 400 faces outwards towards the satellite for thrust vector control.

[0052] like Figure 3 As shown, in this embodiment, the air inlet and air outlet of the air chamber 110 are arranged separately so that the air inlet and air outlet of the air chamber 110 are distributed in different areas inside it.

[0053] In a preferred embodiment, the air inlet end, i.e., the air inlet pipe 500 interface position, and the air outlet end, i.e., the air exchange hole 140 position, of the air chamber 110 are respectively arranged at both ends of the length direction of the air chamber 110, or respectively arranged at two opposite corners of the air chamber 110.

[0054] This layout forces the propellant gas entering the gas chamber 110 to travel a longer path before reaching the outlet, thus avoiding short-circuiting of the airflow, i.e., flowing directly from the inlet to the outlet. This design has a dual beneficial effect: firstly, the airflow diffuses fully within the gas chamber 110, reducing its velocity and buffering pressure fluctuations in the gas supply line, resulting in more stable propellant pressure and flow at the outlet; secondly, it prolongs the residence time of the cryogenic propellant within the gas chamber 110, enhancing the convective heat transfer between the propellant and the wall of the mounting plate 100, thus making the cooling effect more complete.

[0055] like Figure 1 ,as well as Figures 5 to 7 As shown, in this embodiment, the swirl mixer 200 includes a mixer housing 210 and a swirl forming member 220. The mixer housing 210 is sealed around the outlet end of the swirl forming member 220. The inlet end of the mixer housing 210 is connected to the outlet end of one gas chamber 110, and the outlet end of the mixer housing 210 is connected to the inlet end of the combustion chamber nozzle 400. An igniter 300 is provided on the mixer housing 210. The inlet end of the swirl forming member 220 is connected to the outlet end of another gas chamber 110. The outer peripheral wall of the outlet end of the swirl forming member 220 is provided with a plurality of diverting outlet holes 221. The plurality of diverting outlet holes 221 are arranged circumferentially. A swirl guide plate 222 is provided between adjacent diverting outlet holes 221. The swirl guide plate 222 is used to guide the gas output from the diverting outlet holes 221 into a swirl.

[0056] Specifically, in this embodiment, the swirl forming member 220 is generally cylindrical, with an axially extending central channel inside. One end of the central channel is connected to the outlet pipe 150 of the corresponding gas chamber 110 to receive one of the propellants, such as ammonia. On the circumferential wall surface of the swirl forming member 220 near the outlet end, a plurality of, for example, 4 to 8, branch outlet holes 221 are formed. These branch outlet holes 221 are evenly distributed along the circumference, and each branch outlet hole 221 is connected to the central channel. A swirl guide plate 222 extending radially outward is provided on the wall surface between two adjacent branch outlet holes 221. The shape of the swirl guide plate 222 can be straight, curved, or airfoil-shaped. Its function is to guide the gas radially ejected from the branch outlet holes 221 to generate a tangential velocity component, thereby forming a swirling flow rotating around the axis of the swirl mixer 200.

[0057] The mixer housing 210 is a sleeve structure with openings at both ends, and an annular channel is formed between its inner wall and the outer wall of the swirl forming member 220. An air inlet is provided on the side wall of the mixer housing 210, which connects to the outlet pipe 150 of another chamber 110 to receive another propellant, such as nitrous oxide. The axial flow of nitrous oxide and the rotating flow of ammonia mutually shear and collide, forming intense turbulent mixing, achieving a uniform mixing state within a very short distance.

[0058] Igniter 300, such as a spark plug, is installed on the wall of mixer housing 210, with its ignition end extending into the inner cavity of mixer housing 210 or the inlet area of ​​combustion chamber nozzle 400 to reliably ignite the gas mixture.

[0059] like Figure 1 and Figure 6 As shown, in this embodiment, the position where the guide gas of the mixer housing 210 is input into the interior of the mixer along the gas delivery direction of the swirl mixer 200 is located before the part of the swirl forming member 220 that guides the gas into the interior of the mixer housing 210.

[0060] Positioning the air inlet of the mixer housing 210 further upstream means that the propellant, such as nitrous oxide, has a longer flow distance to develop into a more uniform axial flow within the annular channel. By the time it reaches the region of the branch outlet 221 of the swirl forming member 220, its velocity profile is already quite saturated. The other propellant, such as ammonia, enters as a swirling jet only at the branch outlet 221. This mixing mode, with one axial flow and one swirling jet, generates a stronger velocity gradient difference and shear effect compared to an impact mode where both flows are axial or radial, resulting in higher mixing efficiency within a limited space. Furthermore, the axially flowing nitrous oxide also provides film cooling to the inner wall of the mixer housing 210, reducing the wall's thermal load.

[0061] like Figure 1 As shown, in this embodiment, the combustion chamber nozzle 400 includes a first pipe section 410 and a second pipe section 420 that are connected to each other. The adjacent parts of the first pipe section 410 and the second pipe section 420 are both pipe diameter narrowing structures.

[0062] This narrowing pipe section forms the throat of the Laval nozzle. The first pipe section 410 corresponds to the converging section of the combustion chamber and nozzle, with its inner diameter gradually and smoothly shrinking from a larger size at the connection with the swirling mixer 200 to the smallest size at the throat. The second pipe section 420 corresponds to the expanding section of the nozzle, with its inner diameter gradually expanding from the smallest size at the throat to the largest size at the nozzle exit. The throat diameter is a key design parameter determining the engine thrust level and combustion chamber pressure, and must be accurately calculated based on gas dynamics formulas according to the target thrust, the theoretical characteristic velocity of the propellant combination, and the combustion chamber design pressure.

[0063] The combustion chamber nozzle 400 can be made of high-temperature resistant metal materials such as niobium alloys, molybdenum alloys, or high-temperature stainless steel, or ceramic matrix composites can be used to reduce weight and improve temperature resistance. For long-term steady-state operation, regenerative cooling channels can be installed on the combustion chamber wall to cool the wall using unburned propellant before it enters the swirl mixer 200, further improving thermal protection. For pulse-operated attitude control engines, due to the short duration of each pulse and relatively small heat accumulation, radiation cooling can be used to simplify the structure.

[0064] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A dual-component thrust attitude control engine, characterized in that, Includes mounting plate, swirl mixer, igniter and combustion chamber nozzle; The mounting plate has two isolated air chambers inside. The air inlet of each air chamber is connected to an air inlet pipe, and the air outlet of each air chamber is equipped with a controllable solenoid valve. The two inlet ends of the swirling mixture are respectively connected to the outlet ends of the two gas chambers, and the outlet end of the swirling mixer is connected to the inlet end of the combustion chamber nozzle. The swirling mixer is used to swirling mix the gas input into it and output it. The igniter is used to ignite the mixed gas input into the combustion chamber nozzle; The combustion chamber nozzle is used to supply the combustion output of the mixed gas after ignition.

2. The dual-component thrust attitude control engine according to claim 1, characterized in that, The mounting plate has a hollow internal structure and a partition plate inside the mounting plate, which divides the interior of the mounting plate into two air chambers.

3. The dual-component thrust attitude control engine according to claim 1, characterized in that, The solenoid valve is located outside the air chamber.

4. The dual-component thrust attitude control engine according to claim 3, characterized in that, The mounting plate has a valve chamber on its outside, and each of the two valve chambers has a ventilation hole, which is connected to the two air chambers respectively. Both of the air chambers are provided with air outlet pipes, and the air inlet ends of the two air outlet pipes are respectively arranged in the space surrounded by the two air exchange holes. The air outlet ends of the two air outlet pipes are connected to the air inlet end of the cyclone mixer. The two solenoid valves are respectively connected and sealed to the two valve chambers, the air inlet of the two solenoid valves is respectively connected to the two air exchange holes, and the air outlet of the two solenoid valves is respectively connected to the air inlet of the two air outlet pipes.

5. The dual-component thrust attitude control engine according to claim 4, characterized in that, The solenoid valve is equipped with an air guide chamber and a movable and controllable sealing rod; The air guide chamber is connected to the air inlet and air outlet of the solenoid valve; The sealing rod is in a working state where it moves into the outlet end of the solenoid valve to seal the outlet end of the solenoid valve.

6. The dual-component thrust attitude control engine according to claim 3, characterized in that, The air intake pipe and the solenoid valve are both located on the same side of the mounting plate; The swirl mixer, the igniter, and the combustion chamber nozzle are all located on the opposite side of the mounting plate.

7. The dual-component thrust attitude control engine according to claim 1, characterized in that, The air inlet and outlet of the air chamber are arranged separately so that the air inlet and outlet are distributed in different areas inside the air chamber.

8. The dual-component thrust attitude control engine according to claim 1, characterized in that, The cyclone mixer includes a mixer housing and a cyclone forming element; The mixer housing is sealed around the outlet end of the swirl forming member. The inlet end of the mixer housing is connected to the outlet end of the gas chamber. The outlet end of the mixer housing is connected to the inlet end of the combustion chamber nozzle. The igniter is provided on the mixer housing. The inlet end of the swirl forming member is connected to the outlet end of another air chamber. The outer peripheral wall of the outlet end of the swirl forming member is provided with multiple diversion outlet holes. The multiple diversion outlet holes are arranged circumferentially. A swirl guide plate is provided between adjacent diversion outlet holes. The swirl guide plate is used to guide the gas output from the diversion outlet holes into a swirl.

9. The dual-component thrust attitude control engine according to claim 8, characterized in that, Along the gas delivery direction of the swirl mixer, the position where the guide gas of the mixer housing is introduced into its interior is located before the part of the swirl forming member that guides the gas into the interior of the mixer housing.

10. The dual-component thrust attitude control engine according to claim 1, characterized in that, The combustion chamber nozzle includes a first pipe section and a second pipe section that are connected to each other, and the adjacent parts of the first pipe section and the second pipe section are both pipe diameter narrowing structures.

Images