A split modular combined solid rocket engine embedded with a spoiler device and an experimental method thereof

Abstract

The application discloses a split combination solid engine embedded with a disturbance device and an experimental method thereof, and belongs to the technical field of solid rocket engines. The split combination solid engine comprises the disturbance device. The experimental method comprises the following steps of S1, determining the mass flow and component proportion of the flow field gas injected into the engine; S5, replacing the disturbance section device and repeating the experiment; S6, calculating the combustion efficiency of the engine; S7, comparing the combustion efficiencies of the experimental engines; and S8, obtaining the influence of the disturbance device on the combustion efficiency of the engine before and after the disturbance device is added and obtaining the influence law of different disturbance blade numbers on the combustion efficiency of the engine. The disturbance device enhances the mixing degree of the fuel-rich gas and the oxygen-rich gas, reduces the axial flow velocity of the gas, improves the combustion efficiency, and thus improves the performance of the engine. The application injects the fuel-rich gas and the oxygen-rich gas into the air inlet of the experimental device respectively, replaces the process that the propellant grain of the engine self-sustaining combustion generates the gas injected into the flow field of the engine, and simplifies the device and the experimental steps.

Description

Technical Field

[0001] This invention belongs to the field of solid rocket engine technology, specifically relating to a modular solid rocket engine with an embedded turbulence device and its experimental method. Background Technology

[0002] With the rapid development of missile weapon systems, countries worldwide are constantly pursuing improved maneuverability and terminal penetration capabilities, with maneuverability being a particular focus. Active engine performance adjustment ensures that missiles possess the ability to actively adjust their combat trajectory and achieve high flight maneuverability. Active thrust control is typically achieved using liquid propulsion systems. Compared to liquid propulsion systems, solid propulsion systems offer advantages such as easier fuel storage, more complex structure, and shorter pre-launch preparation time. Therefore, developing solid propulsion systems with active performance control capabilities will provide more development directions for missile propulsion systems.

[0003] Currently, research on modular solid rocket motors is still in its early stages both domestically and internationally. Studying combustion mixing in the oxygen-enriched combustion chamber of modular solid rocket motors is of great significance for improving combustion efficiency and enhancing overall engine performance. Summary of the Invention

[0004] To address the problems existing in the prior art, the present invention aims to provide a modular solid rocket motor with an embedded turbulence device and its experimental method, which is used to enhance the mixed combustion of fuel-rich gas and oxygen-rich gas in the oxygen-rich combustion chamber of the engine; to study the influence of adding the turbulence device on the mixed combustion efficiency of the engine, and the influence of different numbers of blades of the mixed device on the mixed combustion efficiency of the engine, so as to provide a reference for engine design.

[0005] The technical solution adopted in this invention is:

[0006] A modular solid rocket motor with an embedded turbulence device includes a cover, a fuel-rich solid propellant grain, an oxygen-rich solid propellant grain, and a fuel-rich combustion chamber, a flow regulating device, a turbulence device, an oxygen-rich combustion chamber, an afterburner, and a nozzle connected in series. The cover is integrally connected to the fuel-rich combustion chamber. The fuel-rich solid propellant grain is bonded to the shell of the fuel-rich combustion chamber using an end-burning propellant grain, and the oxygen-rich solid propellant grain is bonded to the oxygen-rich combustion chamber using a star-shaped propellant grain.

[0007] An experimental method for a modular solid rocket motor with an embedded turbulence device includes the following steps:

[0008] S1. Determine the mass flow rate and component ratio of the gas injected into the engine's internal flow field;

[0009] S2. Install the experimental apparatus and check its airtightness;

[0010] S3. The gas supply equipment is connected to the gas inlet of the experimental device to supply gas to the experimental device;

[0011] S4. Begin the test and monitor the pressure in the combustion chamber;

[0012] S5. Replace the spoiler section device and repeat the experiment;

[0013] S6. Organize monitoring data and calculate engine combustion efficiency;

[0014] S7. Compare the combustion efficiency of the engines in each group of experiments;

[0015] S8. The effects of adding a turbulence device on engine combustion efficiency were determined, and the influence of different numbers of turbulence blades on engine combustion efficiency was determined.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] I. The advantages of modular solid rocket motors are:

[0018] 1. The turbulence device consists of a gas pipeline and turbulence blades. Through integrated design and manufacturing, it eliminates the need for a servo mechanism, greatly improving engine reliability and reducing engine manufacturing costs.

[0019] 2. The turbulence device enhances the mixing of fuel-rich and oxygen-rich gases, reduces the axial flow velocity of the gases, and improves combustion efficiency, thereby improving engine performance.

[0020] 3. The fuel-rich combustion chamber, oxygen-rich combustion chamber, and flow regulation section are connected by a flange, allowing the engine to flexibly replace different turbulence devices to adapt to engines with different performance adjustment capabilities.

[0021] II. The advantages of the experimental method are:

[0022] 1. Compared with traditional ground ignition tests of solid rocket motors assembled separately, this invention uses the air inlet of the experimental device to inject fuel-rich gas and oxygen-rich gas separately, replacing the process of generating gas from the self-sustaining combustion of the engine propellant grain and injecting it into the internal flow field of the engine. This simplifies the device and experimental steps; saves experimental costs and time; improves experimental safety; reduces experimental variables; and allows for a more accurate and singular study of the impact of the turbulence device on the engine's co-combustion efficiency.

[0023] 2. The turbulence section of the experimental apparatus is connected to the main body of the apparatus via a flange, which allows for flexible assembly and easy replacement of the turbulence device. This saves experimental time and costs in studies comparing the effects of adding the turbulence device before and after the addition of the turbulence device, as well as the effects of different turbulence devices on the combustion efficiency of gas mixtures. At the same time, it controls the experimental variables as much as possible and reduces the errors brought to the experimental results by different experimental equipment.

[0024] 3. Using a porous medium pipe reduces the flow rate of oxygen-enriched gas and allows the gas to be injected evenly into the combustion chamber, thus more realistically simulating the gas flow generated by the thermal decomposition of propellant in the oxygen-enriched combustion chamber of a modular solid rocket motor. Attached Figure Description

[0025] Figure 1 This is a schematic cross-sectional view of the modular solid rocket motor of the present invention.

[0026] Figure 2 This is a front view of the turbulence-disrupting device of the present invention;

[0027] Figure 3 This is a side view of the turbulence-disrupting device of the present invention;

[0028] Figure 4 This is an axial sectional view of the main body of the experimental device of the present invention;

[0029] Figure 5 This is a flowchart of the experimental method of the present invention;

[0030] The components are: 1. Cover; 2. Fuel-rich combustion chamber; 3. Flow regulating device; 4. Turbulence device; 5. Oxygen-rich combustion chamber; 6. Afterburner; 7. Nozzle; 8. Fuel-rich solid propellant grain; 9. Oxygen-rich solid propellant grain; 10. Flange; 11. Fuel-rich gas inlet; 12. Flow stabilization section; 13. Turbulence section; 14. Gas mixing section; 15. Porous medium pipe; 16. Oxygen-rich gas inlet; 17. Oxygen-rich gas transition chamber; 18. Combustion chamber; 19. Igniter; 20. Wireless pressure sensor; 21. Tail nozzle. Detailed Implementation

[0031] To better understand the purpose, structure, and function of this invention, the invention will be described in further detail below with reference to the accompanying drawings.

[0032] Reference Figures 1-3 As shown, a modular solid rocket motor with an embedded turbulence device according to the present invention includes a cover 1, a fuel-rich solid propellant grain 8, an oxygen-rich solid propellant grain 9, and a fuel-rich combustion chamber 2, a flow regulating device 3, a turbulence device 4, an oxygen-rich combustion chamber 5, an afterburner 6, and a nozzle 7 connected in series. The cover 1 is integrally connected to the fuel-rich combustion chamber 2. The fuel-rich solid propellant grain 8 is bonded to the shell of the fuel-rich combustion chamber 2 using an end-burning propellant grain, and the oxygen-rich solid propellant grain 9 is bonded to the oxygen-rich combustion chamber 5 using a star-shaped propellant grain.

[0033] like Figures 1-3 As shown, the turbulence device 4 consists of a gas pipeline and multiple turbulence blades arranged symmetrically in the center. The roots of the multiple turbulence blades are integrally connected to the pipe wall of the gas pipeline, which divides the fuel-rich gas into multiple airflow directions and injects them into the oxygen-rich combustion chamber 5.

[0034] The turbulence-causing device 4 can use windmill-type blades to achieve turbulence, eliminating the need for a servo mechanism, which greatly improves the reliability of the engine and reduces the engine's manufacturing cost.

[0035] The surface of the deflector blades is smooth to prevent particles in the combustion gas from accumulating on the surface.

[0036] The working principle of the turbulence device 4 is to divide the fuel-rich gas parallel to the flow channel direction in the flow regulation section of the separately assembled solid rocket motor into multiple airflow directions and inject them into the oxygen-rich combustion chamber 5, thereby enhancing the mixing degree of the fuel-rich gas and the oxygen-rich gas, improving combustion efficiency, and thus improving engine performance.

[0037] Furthermore, by altering the direction of gas flow through deflector blades, the airflow velocity is reduced, increasing the residence time of the gas in the oxygen-rich combustion chamber. This allows the fuel-rich gas to fully react with the oxygen-rich gas, improving combustion efficiency and thus enhancing engine performance.

[0038] Flow regulating device 3 adopts a flow regulating valve;

[0039] The flow regulating device 3 and the turbulence-enhancing device 4 are integrated to form the flow regulating section. The fuel-rich combustion chamber 2, the flow regulating section, and the oxygen-rich combustion chamber 5 are connected in series via flange 10. This facilitates the replacement of the engine's turbulence-enhancing device to accommodate different adjustable solid rocket motors.

[0040] The oxygen-enriched combustion chamber 5 and the afterburner 6 are connected by a flange 10, and the nozzle 7 and the afterburner 6 are designed as a single unit.

[0041] The fuel-rich solid propellant grain 8 sustains combustion to generate fuel-rich gas; the fuel-rich gas is injected into the oxygen-rich combustion chamber 5 through the flow regulating valve and the turbulence device 4, where it mixes and burns with the oxygen-rich gas generated in the oxygen-rich combustion chamber 5 to release heat, and finally the gaseous products are expanded and accelerated through the nozzle 7 to generate thrust.

[0042] Experimental methods, such as Figure 4 As shown, it includes the following steps:

[0043] S1. Based on the engine's chemical reaction mechanism, determine the thermal decomposition products and component proportions of the fuel-rich and oxygen-rich propellants; and use Fluent software to calculate the pressures of the two combustion chambers during stable engine operation, combined with the combustion surface area of ​​the fuel-rich and oxygen-rich propellant grains, to calculate the mass flow rate and component proportions of the propellant gas injected into the engine's internal flow field.

[0044] S2. Install the experimental apparatus and check its airtightness;

[0045] S3. The gas supply equipment is connected to the gas inlet of the experimental device to supply gas to the experimental device;

[0046] The gas supply equipment injects fuel-rich gas and oxygen-rich gas with the same mass flow rate and component ratio through the air inlet of the experimental device, replacing the process of generating gas from the self-sustaining combustion of the engine propellant grain and injecting it into the internal flow field of the engine. This simplifies the device and experimental steps, saves experimental costs and time, improves experimental safety, reduces experimental variables, and allows for a more accurate and singular study of the impact of the turbulence device on the engine's co-combustion efficiency.

[0047] S4. Begin the test and monitor the pressure in the combustion chamber;

[0048] S5. Repeat the experiment by changing the spoiler section device (without adding the spoiler device, and with adding spoilers of different numbers of blades);

[0049] S6. Organize monitoring data and calculate engine combustion efficiency;

[0050] S7. Compare the combustion efficiency of the engines in each group of experiments;

[0051] S8. The effects of adding a turbulence device on engine combustion efficiency were determined, and the influence of different numbers of turbulence blades on engine combustion efficiency was determined.

[0052] Among them: such as Figure 4 As shown, the experimental setup in S2 includes a flow stabilizing section 12, a flow turbulence section 13, a gas mixing section 14, a combustion chamber 18, and a tailpipe 21, which are detachably connected in series via flanges. To achieve better airtightness, each experimental device is welded to the flanges, allowing for flexible assembly between sections. The flanges are fixed together using 12 connection ports. Figure 4 As shown.

[0053] The gas mixing section 14 is externally fitted with an oxygen-enriched gas transition chamber 17. The top and bottom of the oxygen-enriched gas transition chamber 17 are integrally provided with oxygen-enriched gas inlets 16. The oxygen-enriched gas transition chamber 17 is connected to the gas mixing section 14 through a porous medium pipe 15 embedded in its groove. Multiple wireless pressure sensors 20 are welded inside the combustion chamber 18. An igniter 19 is installed on the combustion chamber 18. The gas-enriched gas inlet 11 and the oxygen-enriched gas inlet 16 at the head of the flow stabilization section 12 are both connected to the gas supply system through hoses. The gas supply system delivers the gas in the high-pressure gas cylinder to the flow stabilization section 12 and the oxygen-enriched gas transition chamber 17 respectively through pressure valves.

[0054] Rich gas is introduced into the fuel-rich gas inlet 11 of the experimental device to simulate the fuel-rich gas generated by the self-sustaining combustion of fuel-rich propellant in a solid rocket motor. In the steady flow section 12 of the experimental device, the gas flow in the flow regulation section of the solid rocket motor is simulated. Oxygen-rich gas is introduced into the oxygen-rich gas transition chamber 17 at the top and bottom of the gas mixing section 14 of the experimental device. The flow velocity of the oxygen-rich gas is reduced by the porous medium pipe 15, and the gas is uniformly injected into the combustion chamber 18 to more realistically simulate the gas flow generated by the thermal decomposition of oxygen-rich propellant in the oxygen-rich combustion chamber of the solid rocket motor.

[0055] The turbulence section 13 of the experimental device is connected to the main body of the device via a flange, which allows for flexible assembly and easy replacement of the turbulence device. In the study comparing the effects of adding the turbulence device before and after the addition of the turbulence device and the effects of different turbulence devices on the combustion efficiency of gas mixture, experimental time and cost are saved. At the same time, the experimental variables are controlled as much as possible, and the errors brought to the experimental results by different experimental equipment are reduced.

[0056] Before the experiment, an airtightness test was conducted on the experimental setup. To ensure the entire test section was a closed system, the outlet of the tailpipe 21 and the oxygen-enriched gas inlet 16 were sealed with caps, and the oxygen-enriched gas inlet 11 was connected to the gas supply system via a hose. Simultaneously, all bolt connections were pre-tightened using a diagonal pre-tightening method to ensure uniform force distribution and prevent bolt overload. The inlet valve was opened to allow the pressure to rise slowly. Once a certain pressure was reached, it was held for 10 minutes. The airtightness of the setup was judged by whether a buzzing sound was emitted. If a buzzing sound was emitted, the source of the sound was located, the cause was analyzed, and modifications and reinforcements were made. The experiment could only proceed after the airtightness of the experimental setup was deemed satisfactory.

[0057] Furthermore, in S6, the characteristic velocity method is used to characterize the engine's combustion efficiency:

[0058] The characteristic velocity is defined as:

[0059]

[0060] In the formula: C * Indicates characteristic velocity; A t P represents the area of ​​the nozzle throat. c * Indicates the total pressure of the combustion chamber; This indicates the mass flow rate through the nozzle;

[0061] Calculation of theoretical characteristic velocity:

[0062]

[0063] In the formula: C th *R0 represents the theoretical characteristic velocity; T represents the universal gas constant. f Indicates the adiabatic combustion temperature; τ represents the average molecular weight of the gas-phase combustion products; τ represents the specific heat ratio function.

[0064] Combustion efficiency:

[0065]

[0066] The combustion chamber pressure is monitored using six wireless pressure sensors 20 on the wall of the combustion chamber. The highest and lowest values ​​monitored by the six wireless pressure sensors 20 are removed, and the average of the remaining four values ​​is used to represent the combustion chamber pressure P. c * This avoids errors caused by equipment damage and the equipment's own precision errors; according to the law of conservation of mass, the mass flow rate at the nozzle... The mass flow rate of the combustion gas was the same as that of the injection experimental device; based on the engine chemical reaction mechanism, the parameters of the theoretical combustion products were calculated using Chemkin software.

[0067] It is understood that the present invention has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the invention. Furthermore, under the teachings of the present invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of the present invention.

Claims

1. An experimental method for a modular solid rocket motor with an embedded turbulence device, characterized in that: Includes the following steps: S1. Determine the mass flow rate and component ratio of the gas injected into the engine's internal flow field; S2. Install the experimental apparatus and check its airtightness; S3. The gas supply equipment is connected to the gas inlet of the experimental device to supply gas to the experimental device; S4. Begin the test and monitor the pressure in the combustion chamber; S5. Replace the spoiler section device and repeat the experiment; S6. Organize monitoring data and calculate engine combustion efficiency; S7. Compare the combustion efficiency of the engines in each group of experiments; S8. Determine the impact of adding a baffle device on engine combustion efficiency, and derive the influence of different numbers of baffle blades on engine combustion efficiency. The experimental setup in S2 includes a flow stabilizing section (12), a turbulence section (13), a gas mixing section (14), a combustion chamber (18), and a tail nozzle (21) that are detachably connected in series. The gas mixing section (14) is externally fitted with an oxygen-enriched gas transition chamber (17). The top and bottom of the oxygen-enriched gas transition chamber (17) are integrally provided with oxygen-enriched gas inlets (16). The oxygen-enriched gas transition chamber (17) is connected to the gas mixing section (14) through a porous medium pipe (15) embedded in its groove. Multiple wireless pressure sensors (20) are welded inside the combustion chamber (18). An igniter (19) is installed on the combustion chamber (18). The gas-enriched gas inlet (11) and the oxygen-enriched gas inlet (16) at the head of the flow stabilizing section (12) are both connected to the gas supply system. The gas supply device in S3 injects fuel-rich gas and oxygen-rich gas with the same mass flow rate and component ratio through the air inlet of the experimental device, respectively, to replace the self-sustaining combustion of the engine propellant grain to generate gas that is injected into the internal flow field of the engine.

2. The experimental method for the modular assembly of a solid rocket motor with an embedded turbulence device according to claim 1, characterized in that: The specific steps for determining the mass flow rate and component ratio of the gas injected into the engine internal flow field in S1 are as follows: based on the engine chemical reaction mechanism, determine the thermal decomposition products and component ratios of the fuel-rich and oxygen-rich propellants; and calculate the pressure of the two combustion chambers of the engine during stable operation, combined with the burning surface area of ​​the fuel-rich and oxygen-rich propellant grains, thereby calculating the mass flow rate and component ratio of the gas injected into the engine internal flow field.

3. The experimental method for the modular assembly of a solid rocket motor with an embedded turbulence device according to claim 1, characterized in that: In S5, the repeated experiment is to conduct experiments without adding a turbulence device and with adding different numbers of turbulence blades.

4. The experimental method for the modular solid rocket motor with embedded turbulence device according to claim 1, characterized in that: In step S6, the characteristic velocity method is used to characterize the combustion efficiency of the engine: The characteristic velocity is defined as: In the formula: Indicates characteristic velocity; Indicates the area of ​​the nozzle throat; Indicates the total pressure of the combustion chamber; This indicates the mass flow rate through the nozzle; Calculation of theoretical characteristic velocity: In the formula: Indicates the theoretical characteristic velocity; Represents the universal gas constant; Indicates the adiabatic combustion temperature; This represents the average molecular weight of the gas-phase combustion products. Represents the specific heat ratio function; Combustion efficiency: 。

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