Solid rocket engine pintle and air cooling structure

Abstract

The invention relates to a solid rocket engine pintle and an air cooling structure, a head part is formed at one end of the pintle, and a gas collecting cavity is formed in the head part; a plurality of air film holes are also formed in the inner wall of the head part and are respectively communicated with the air collecting cavity and the outer wall surface of the throat bolt; a propellant cavity is further formed in the throat bolt, and a low-combustion-temperature propellant is arranged in the propellant cavity; a pressure stabilizing cavity is further formed in the throat bolt, one side of the pressure stabilizing cavity is directly communicated with the propellant cavity, and the other side of the pressure stabilizing cavity is communicated with the gas collecting cavity through a jet flow channel. According to the scheme, the cooling protection device is compact in structure, stable in performance and wide in cooling range, the cooling protection problem of two large high-temperature areas of the throat bolt head and the equivalent throat area can be effectively solved, the throat bolt can be effectively prevented from being ablated by high-temperature gas, and a foundation is laid for improving the performance of a thrust follow-up control engine and the thrust control precision.

Description

Technical Field

[0001] This application relates to a throat plug and gas-cooling structure for a solid rocket motor, and is applicable to the technical field of solid rocket motors. Background Technology

[0002] Throat-plug type thrust-following solid rocket motor refers to a solid rocket motor that applies throat-plug type nozzle technology to a traditional solid rocket motor to achieve thrust adjustment. The thrust adjustment is accomplished by the throat plug being driven by a control servo mechanism to reciprocate (mutually changing motion) within the nozzle. A key consideration in its design is the throat plug ablation problem.

[0003] Although much research has been conducted both domestically and internationally on throat-plug-type variable thrust solid rocket motors, there is a lack of research specifically addressing the throat plug ablation mechanism under real-world conditions, and reports on throat plug ablation are scarce; currently, there is a lack of necessary understanding of the throat plug ablation problem. Furthermore, existing research indicates that the use of high-temperature propellants directly causes severe ablation of the throat plug head, reducing the accuracy of engine thrust adjustment and engine performance.

[0004] There are currently no publicly available documents concerning the throat plug impact gas-cooled structure technology for thrust-guided solid rocket motors.

[0005] Therefore, existing technologies require a throat plug and gas-cooling structure for solid rocket motors. Summary of the Invention

[0006] The purpose of this application is to design a throat plug and air-cooling structure for a solid rocket motor, aiming to solve the problem of ablation at the head of the throat plug in existing solid rocket motors.

[0007] This application relates to a throat plug for a solid rocket motor. One end of the throat plug forms a head, and the head has a gas collecting chamber. The inner wall of the head also has multiple gas film holes, which are connected to the gas collecting chamber and the outer wall of the throat plug, respectively. The throat plug also has a propellant chamber containing a low-burning-temperature propellant. The throat plug also has a pressure stabilizing chamber, one side of which is directly connected to the propellant chamber, and the other side of which is connected to the gas collecting chamber through a jet channel.

[0008] In some embodiments, the top end of the air collecting chamber is provided with an air outlet guide component, and the air outlet guide component is provided with a guide pipe, which is connected to the air collecting chamber and the guide port at the outer end of the throat plug, respectively.

[0009] In some embodiments, the air outlet guide component is a guide cone, with the tip of the guide cone facing the center of the jet channel, so that the guide tube and the jet channel are coaxially arranged.

[0010] In some implementations, the diameter of the laryngeal plug is D; the length M of the jet channel satisfies: M≥1.5D.

[0011] In some implementations, the diameter of the jet channel is K, and the distance N between the jet channel and the air outlet guide component satisfies: K≤N≤5K.

[0012] In some implementations, the diameter of the laryngeal plug is D; the length L of the pressure-stabilizing cavity satisfies: 0.8D≤L.

[0013] In some embodiments, multiple air film holes are evenly distributed in the circumferential direction of the head; the included angle β between two adjacent air film holes ranges from 8° to 20°.

[0014] In some implementations, the diameter J of the air film pores ranges from 0.3 mm to 10 mm.

[0015] In some implementations, the inclination angle γ of the air film pores ranges from 20° to 60°.

[0016] In some implementations, the diameter D of the laryngeal plug ranges from 6 mm to 50 mm.

[0017] In some implementations, the length of the head ranges from 3mm to 40mm.

[0018] In some implementations, the diameter I of the guide tube ranges from 0.3 mm to 15 mm.

[0019] In some implementations, the rounding diameter E of the flow guide is in the range of 1mm-4mm.

[0020] In some implementations, the cone angle α of the guide cone ranges from 10° to 40°.

[0021] In some embodiments, the head and the air collection chamber are both conical structures; multiple air film pores are distributed in the upstream region at the location of the equivalent laryngeal area of ​​the laryngeal plug.

[0022] This application also provides a solid rocket motor air-cooling structure, including a throat plug and an engine; the throat plug is the solid rocket motor throat plug described above; the throat plug is also provided with a driving device; the engine is provided with a gas generator; the throat plug is telescopically mounted on the engine; the gas generated by the gas generator can be mixed with the gas ejected from the gas film orifice to form a protective gas film.

[0023] In some implementations, the low-temperature propellant in the throat plug operates for a longer time than the engine operates, and the low-temperature propellant is ignited before the engine.

[0024] The solid rocket motor throat plug and gas-cooling structure proposed in this application have the following technical advantages:

[0025] (1) The solid rocket engine throat plug and gas-cooling structure proposed in this invention allow the high-pressure cryogenic gas generated after the combustion of low-temperature propellant to enter the pressure stabilizing chamber, then expand and accelerate through the jet orifice, directly impacting the exhaust guide component and building pressure in the gas collection chamber. The gas is then ejected from the exhaust guide component and the film gas hole, forming an effective film of protection on the outer wall of the throat plug. The combination of the exhaust guide component and the jet orifice designed in this application can effectively improve the local heat transfer coefficient through impact, thereby reducing the throat plug head temperature. Simultaneously, the cryogenic gas, after passing through the exhaust guide component, will cause disturbance in the recirculation zone, thereby reducing the recirculation vortex intensity and decreasing the local heat transfer temperature. This dual effect effectively reduces the wall temperature of the throat plug head area, preventing it from being ablated by high-temperature gas, while simultaneously improving the engine's aerodynamic performance. Furthermore, after being ejected through the film gas hole, the cryogenic gas forms an effective film of protection on its outer wall, thus effectively reducing the occurrence of throat plug ablation at the minimum equivalent throat area.

[0026] (2) The solid rocket engine throat plug and air-cooled structure proposed in this invention are compact, have a wide cooling range and stable performance. They can effectively solve the ablation problem of the two high-temperature areas at the throat plug head and the equivalent throat area, reduce the aerodynamic loss caused by the backflow vortex, and effectively protect the throat plug from ablation by high-temperature gas. This lays the foundation for improving the performance and thrust control accuracy of the thrust follow-up engine. Attached Figure Description

[0027] Figure 1 This is an overall schematic diagram of a solid rocket motor throat plug according to this application.

[0028] Figure 2 This is a cross-sectional view of a solid rocket motor throat plug according to this application.

[0029] Figure 3 This is a side view of a solid rocket motor throat plug according to this application.

[0030] Figure 4 This is a schematic diagram of the air-cooled structure of a solid rocket motor according to this application.

[0031] In the diagram: 1. Throat plug; 2. Guide cone; 3. Film gas orifice; 4. Jet channel; 5. Pressure stabilizing chamber; 6. Low-temperature propellant; 7. Gas collection chamber; 8. Engine; 81. Nozzle; 9. Gas generator; 10. Drive unit; C. Throat plug head length; D. Throat plug diameter; E. Throat plug head guide orifice rounding diameter; F. Exit guide cone bottom rounding diameter; H. Distance between the exit guide cone and the throat plug head; I. Diameter of the guide tube in the exit guide cone; J. Film gas orifice diameter; K. Jet orifice diameter; L. Pressure stabilizing chamber length; M. Jet orifice length; N. Distance between the jet orifice and the exit guide cone; P. Pressure stabilizing chamber diameter; α. Exit guide cone cone angle; β. Film gas orifice period; γ. Film gas orifice inclination angle. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other. Those skilled in the art will understand that the solid rocket motor throat plug of this application is applicable to thrust-following solid rocket motors to solve the problem of throat plug erosion by high-temperature combustion gases.

[0033] like Figure 1-4As shown, this application proposes a throat plug for a solid rocket motor, specifically a thrust-following solid rocket motor throat plug, applicable to thrust-following solid rocket motors. Specifically, one end of the throat plug 1 forms a head, and the head contains a gas collecting chamber 7; furthermore, the inner wall of the head is provided with multiple film gas holes 3, each film gas hole 3 communicating with the gas collecting chamber 7 and the outer wall surface of the throat plug respectively; furthermore, the throat plug 1 also contains a propellant chamber, which contains a low-burning-temperature propellant 6; furthermore, the throat plug 1 also contains a pressure stabilizing chamber 5, one side of which is directly connected to the propellant chamber, and the other side of which is connected to the gas collecting chamber 7 through a jet channel 4. Furthermore, the top end of the gas collecting chamber 7 is provided with an exhaust guide component, which is designed as a guide cone 2. Specifically, in the above structure, the high-pressure, low-temperature gas generated after the combustion of the low-temperature propellant 6 enters the pressure stabilizing chamber 5, then expands and accelerates through the jet orifice 4, directly impacting the guide cone 2 and building pressure in the gas collecting chamber 7. It then exits from the outlet guide cone 2 and the film gas orifice 3, forming an effective film of gas protection on the throat plug wall. Under normal circumstances, the high-temperature gas in the engine forms a backflow vortex in the head region of the throat plug, creating a high-temperature area. The combination of the guide cone 2 and the jet orifice 4 can effectively increase the local heat transfer coefficient through impact, thereby reducing the throat plug head temperature. Furthermore, the low-temperature gas, after passing through the outlet guide cone 2, will disturb the backflow area, reducing the intensity of the backflow vortex and decreasing the local heat transfer temperature. This dual effect effectively reduces the wall temperature in the throat plug head region, preventing it from being burned by the high-temperature gas, while simultaneously improving the engine's aerodynamic performance. After the low-temperature gas is ejected through the gas film hole 3, it will form an effective gas film protection on its outer wall, which can effectively reduce the occurrence of throat plug ablation at the minimum equivalent throat area.

[0034] The solid rocket motor throat plug proposed in this application has a compact structure, stable performance, and wide cooling range. It can effectively solve the problem of cooling and protection of the two high-temperature regions at the throat plug head and the equivalent throat area. It can also reduce aerodynamic losses caused by backflow vortices and effectively protect the throat plug from being burned by high-temperature combustion gases, laying the foundation for improving the performance and thrust control accuracy of thrust follow-up engines.

[0035] like Figure 1-4 As shown, in some embodiments, the top end of the gas collecting chamber 7 is provided with an outlet guide component, and the outlet guide component is provided with a guide pipe, which is connected to the guide port of the gas collecting chamber 7 and the outer end (i.e., the tip) of the throat plug 1. Specifically, the high-pressure, low-temperature gas generated after the low-temperature propellant 6 burns will enter the pressure stabilizing chamber 5, and then expand and accelerate through the jet hole 4, directly impacting the outlet guide cone 2, and building pressure in the gas collecting chamber 7. Then it will be ejected from the outlet guide cone 2 and the gas film hole 3 respectively, forming an effective gas film protection on the outer wall surface of the head of the throat plug.

[0036] like Figure 1-4 As shown, in some embodiments, the outlet guide component is a guide cone 2, the tip of which faces the center of the jet channel 4, thereby making the guide tube and the jet channel 4 coaxially arranged. Furthermore, the cone angle α of the guide cone is in the range of 10°-40°, which can minimize the aerodynamic losses caused by backflow vortices.

[0037] like Figure 1-4 As shown, in some embodiments, the diameter of the throat plug 1 is D; the length M of the jet channel 4 satisfies: M≥1.5D. Further, the diameter of the jet channel 4 is K, and the distance N between the jet channel 4 and the exhaust guide component satisfies: K≤N≤5K. Further, the length L of the pressure stabilizing chamber 5 satisfies: 0.8D≤L. The above structural dimensions are designed based on actual research to optimize the combustion and injection effect of the low-temperature propellant 6 within the throat plug.

[0038] like Figure 1-4 As shown, in some embodiments, multiple film vents 3 are evenly distributed circumferentially on the head; the included angle β between two adjacent film vents 3 ranges from 8° to 20°. Further, the diameter J of the film vents 3 ranges from 0.3 mm to 10 mm. Further, the inclination angle γ of the film vents 3 ranges from 20° to 60°. The above structural dimensions are designed based on actual research and can effectively solve the ablation problem in the two high-temperature areas at the throat head and the equivalent throat area in practical applications. It can effectively protect the throat from ablation by high-temperature combustion gases, thereby improving the performance and thrust control accuracy of the thrust-following engine.

[0039] like Figure 1-4 As shown, in some embodiments, the diameter D of the laryngeal plug 1 ranges from 6mm to 50mm. Furthermore, the length of the head ranges from 3mm to 40mm. This structural dimension design effectively ensures that the two high-temperature regions at the equivalent laryngeal area of ​​the head of the laryngeal plug 1 are cooled and protected.

[0040] like Figure 1-4 As shown, in some embodiments, the diameter I of the guide tube ranges from 0.3 mm to 15 mm. Furthermore, the rounding diameter E of the guide orifice ranges from 1 mm to 4 mm. This structural dimension design allows the high-pressure gas ejected from the guide tube to form a protective gas film at the tip of the throat plug 1.

[0041] like Figure 1-4 As shown, in some embodiments, the head of the laryngeal plug 1 and the air-collecting chamber 7 are both conical structures; multiple air film holes 3 are distributed in the upstream region at the location of the equivalent laryngeal area of ​​the laryngeal plug, thereby effectively protecting the laryngeal plug from ablation. Specifically, refer to Figure 4As shown, the equivalent throat area of ​​the throat plug is located at the point of minimum cross-sectional area between the throat plug and the inner wall of the nozzle 81 of the engine 8. The upstream region specifically refers to the region in front of the point where the equivalent throat area of ​​the throat plug is located along the direction of gas flow.

[0042] like Figure 1-4 As shown, this application also provides a solid rocket motor gas-cooling structure, specifically including a throat plug 1 and an engine 8; wherein, the throat plug 1 is the aforementioned solid rocket motor throat plug. Further, the throat plug 1 is also provided with a driving device 10, which is used to drive the throat plug 1 to extend and retract within the engine 8. Further, the engine 8 is provided with a gas generator 9; the throat plug 1 is telescopically mounted on the engine 8; the gas generated by the gas generator 9 can mix with the gas ejected from the film gas hole 3, thereby forming a protective film gas. The solid rocket motor gas-cooling structure provided in this application can solve the problem that severe throat plug ablation in thrust-following engines under high combustion temperature conditions seriously affects the engine thrust adjustment accuracy and engine performance.

[0043] like Figure 1-4 As shown, in some embodiments, the low-temperature propellant 6 in the throat plug 1 operates for a longer time than the engine 8, and the low-temperature propellant 6 is ignited before the engine 8 to achieve a protective effect.

[0044] like Figure 1-4 As shown, in the solution provided in this application, the drive device 10 can control the movement of the throat plug 1 in the engine 8, thereby effectively regulating the pressure in the engine 8 to achieve the purpose of thrust regulation. The high-pressure, low-temperature gas generated after the combustion of the low-temperature propellant 6 enters the pressure stabilizing chamber 5, and then expands and accelerates through the jet hole 4, directly impacting the exhaust guide cone 2, and building pressure in the gas collecting chamber 7. Then, it is ejected from the exhaust guide cone 2 and the gas film hole 3 respectively, and mixes with the high-temperature gas generated in the gas generator 9 to form an effective gas film protection. Increasing the rounded diameter of the flow guide orifice at the head of the laryngeal plug can improve the coverage area of ​​the air film at the head of the laryngeal plug 1 after the jet leaves the plug 1; a larger distance N between the jet orifice 4 and the outlet flow guide cone 2 results in a weaker impact effect and increased heat transfer at the head, but it can effectively increase the flow distribution of the secondary flow in the air film orifice 3, thereby improving the local air film cooling performance; decreasing the distance N between the jet orifice 4 and the outlet flow guide cone 2 can effectively improve local heat transfer and effectively reduce the temperature at the head of the laryngeal plug; increasing the rounded diameter F of the bottom edge of the outlet flow guide cone 2 can reduce the local aerodynamic loss of the flow inside the laryngeal plug; decreasing the period β of the air film orifice 3 can increase the spanwise coverage area of ​​the air film, but it will also reduce the coverage effect of the air film along the flow direction; decreasing the diameter K of the jet orifice 4 can enhance the impact heat transfer effect inside the laryngeal plug; increasing the length L of the pressure stabilizing chamber 5 can improve the stability and uniformity of the flow inside the laryngeal plug.

[0045] The solid rocket motor throat plug and gas-cooling structure proposed in this application have the following technical advantages:

[0046] (1) The solid rocket engine throat plug and gas-cooling structure proposed in this invention allow the high-pressure cryogenic gas generated after the combustion of low-temperature propellant to enter the pressure stabilizing chamber, then expand and accelerate through the jet orifice, directly impacting the exhaust guide component and building pressure in the gas collection chamber. The gas is then ejected from the exhaust guide component and the film gas hole, forming an effective film of protection on the outer wall of the throat plug. The combination of the exhaust guide component and the jet orifice designed in this application can effectively improve the local heat transfer coefficient through impact, thereby reducing the throat plug head temperature. Simultaneously, the cryogenic gas, after passing through the exhaust guide component, will cause disturbance in the recirculation zone, thereby reducing the recirculation vortex intensity and decreasing the local heat transfer temperature. This dual effect effectively reduces the wall temperature of the throat plug head area, preventing it from being ablated by high-temperature gas, while simultaneously improving the engine's aerodynamic performance. Furthermore, after being ejected through the film gas hole, the cryogenic gas forms an effective film of protection on its outer wall, thus effectively reducing the occurrence of throat plug ablation at the minimum equivalent throat area.

[0047] (2) The solid rocket engine throat plug and air-cooled structure proposed in this invention are compact, have a wide cooling range and stable performance. They can effectively solve the ablation problem of the two high-temperature areas at the throat plug head and the equivalent throat area, reduce the aerodynamic loss caused by the backflow vortex, and effectively protect the throat plug from ablation by high-temperature gas. This lays the foundation for improving the performance and thrust control accuracy of the thrust follow-up engine.

[0048] Although the embodiments disclosed in this application are as described above, the content is merely for the purpose of facilitating understanding of this application and is not intended to limit this application. Any person skilled in the art to which this application pertains may make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in this application; however, the scope of patent protection of this application shall still be determined by the scope defined in the appended claims.

Claims

1. A throat plug for a solid rocket motor, characterized in that, One end of the throat plug (1) forms a head, and the head is provided with an air collecting chamber (7); the inner wall of the head is also provided with a plurality of air film holes (3), and the air film holes (3) are respectively connected to the air collecting chamber (7) and the outer wall surface of the throat plug; the throat plug (1) is also provided with a propellant chamber, and the propellant chamber is provided with a low-burning-temperature propellant (6); the throat plug (1) is also provided with a pressure stabilizing chamber (5), one side of the pressure stabilizing chamber (5) is directly connected to the propellant chamber, and the other side of the pressure stabilizing chamber (5) is connected to the air collecting chamber (7) through a jet channel (4).

2. The solid rocket motor throat plug according to claim 1, characterized in that, The top end of the gas collecting chamber (7) is provided with an air outlet guide component, and the air outlet guide component is provided with a guide pipe. The guide pipe is connected to the guide port at the outer end of the gas collecting chamber (7) and the throat plug (1).

3. The solid rocket motor throat plug according to claim 2, characterized in that, The air outlet guide component is a guide cone (2), and the tip of the guide cone (2) faces the center of the jet channel (4), so that the guide tube and the jet channel (4) are coaxially arranged.

4. The solid rocket motor throat plug according to claim 1, characterized in that, The diameter of the throat plug (1) is D; the length M of the jet channel (4) satisfies: M≥1.5D; and / or, the diameter of the jet channel (4) is K, and the distance N between the jet channel (4) and the air outlet guide component satisfies: K≤N≤5K; and / or, the length L of the pressure stabilizing chamber (5) satisfies: 0.8D≤L.

5. The solid rocket motor throat plug according to claim 1, characterized in that, The plurality of air film holes (3) are evenly distributed in the circumferential direction of the head; the included angle β between two adjacent air film holes (3) is in the range of 8°-20°; and / or, the diameter J of the air film hole (3) is in the range of 0.3mm-10mm; and / or, the hole inclination angle γ of the air film hole (3) is in the range of 20°-60°.

6. The solid rocket motor throat plug according to claim 1, characterized in that, The diameter D of the laryngeal plug (1) is in the range of 6mm-50mm; and / or the length of the head is in the range of 3mm-40mm.

7. The solid rocket motor throat plug according to claim 3, characterized in that, The diameter I of the guide tube is in the range of 0.3mm-15mm; and / or the rounding diameter E of the guide port is in the range of 1mm-4mm; and / or the cone angle α of the guide cone (2) is in the range of 10°-40°.

8. The solid rocket motor throat plug according to claim 1, characterized in that, The head and the air collection chamber (7) are both conical structures; the plurality of air film holes (3) are distributed in the upstream region at the equivalent laryngeal area of ​​the laryngeal plug (1).

9. A gas-cooled structure for a solid rocket motor, comprising a throat plug (1) and an engine (8); characterized in that, The throat plug (1) is the throat plug of a solid rocket engine as described in any one of claims 1 to 8; the throat plug (1) is also provided with a driving device (10); the engine (8) is provided with a gas generator (9); the throat plug (1) is telescopically mounted on the engine (8); the gas generated by the gas generator (9) can be mixed with the gas ejected from the gas film hole (3) to form a protective gas film.

10. The gas-cooled structure for a solid rocket motor according to claim 9, characterized in that, The low-temperature propellant (6) in the throat plug (1) operates for a longer time than the engine (8), and the low-temperature propellant (6) is ignited before the engine (8).

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