Single-chamber double-thrust solid rocket engine charging structure

Abstract

The invention belongs to the field of solid rocket engine design, and provides a single-chamber double-thrust solid rocket engine charging structure which is installed in an engine combustion chamber shell and above a heat insulation layer and is composed of a coating layer, boosting-stage charging and endurance-stage charging, the coating layer coats the outer side of a boosting-stage charging cavity and the outer side of an endurance-stage charging cavity, and the boosting-stage charging cavity and the endurance-stage charging cavity are communicated with each other. The boosting-level charge is arranged at one end, close to a spray pipe, in an engine combustion chamber, the endurance-level charge is arranged at the other end, away from the spray pipe, in the combustion chamber, an air layer is arranged between the boosting-level charge and the endurance-level charge, and the boosting-level charge and the endurance-level charge do not make direct contact with each other. The boosting-level charging structure and the endurance-level charging structure are arranged in the mode that end-burning grains are embedded into a net array structure. According to the invention, through organic combination of the full-filling end combustion charging technology and the embedded net array speed control technology, the requirements of the maximum filling ratio and low-thrust long-time working are met, the negative mass of an engine is reduced, the safety requirement and the use risk of the engine are met, and the development of miniaturization and light weight of weaponry is effectively promoted.

Description

Technical Field

[0001] The invention belongs to the field of solid rocket engine design, and in particular relates to a single-chamber dual-thrust solid rocket engine charge structure. Background Art

[0002] Solid rocket engines are currently the most widely used power devices in the field of tactical missiles because of their simple structure, easy use, high reliability and long-term storage. In order to meet the requirements of large thrust boost launch and low thrust long-term flight of air-to-surface vehicles, single-chamber dual-thrust, dual-pulse, dual-chamber dual-thrust and other solid rocket engines have been vigorously developed and gradually become efficient power devices in the field of air-to-surface weapons. However, with the increasing demand for lightweight, miniaturized and cost-controlled combat of air-to-surface vehicles, solid rocket engines that account for more than half of the weight and volume of aircraft and 30% of the total cost of missiles are also facing increasingly stringent technical requirements. Compared with single-chamber dual-thrust solid rocket engines, dual-pulse and dual-chamber dual-thrust solid rocket engines have more advantages in energy management and working time, but the negative mass increase and volume increase caused by the additional structure make them lack competitiveness in lightweight and miniaturization, and the added ignition device also leads to higher costs. Therefore, it is particularly important to develop single-chamber dual-thrust solid rocket engines.

[0003] At present, in order to achieve two thrust changes in the same combustion chamber, the single-chamber dual-thrust solid rocket engine mainly adopts a large-burning-surface booster stage and a small-burning-surface endurance stage. The booster stage is generally a large-burning-surface charge such as an inner tube, an inner hole star, and a wing column, while the endurance stage generally adopts an end-face burning charge to achieve the working requirements of large thrust boost and small thrust endurance. Although the booster-stage charge is effectively increased by opening a hole groove in the middle to achieve a high-thrust launch, the existence of the hole groove also makes the space utilization rate of the charge column not high. Compared with the end-burning charge column with the highest loading ratio, the space occupied by it is significantly increased, which leads to an increase in the volume of related structures such as the insulation layer and the shell on the outside of the charge column, which will eventually lead to an increase in the volume of the engine and a decrease in the mass number. At the same time, the increase in related structures such as insulation and shells will also lead to an increase in the raw materials required for production, and the production cost of the engine will also increase accordingly, which is very unfavorable for the development of weapons and equipment that pursue miniaturization, lightweight, and cost control.

[0004] In order to solve the problems of low space utilization and low mass number of the conventional single-chamber dual-thrust solid rocket engine propellant, a new single-chamber dual-thrust solid rocket engine propellant structure was proposed by combining the fully filled end-burning propellant column configuration and the embedded grid array speed control technology. Summary of the invention

[0005] The purpose of the present invention is to improve the filling ratio of the engine combustion chamber and increase the engine mass number, thereby achieving a reduction in the volume and mass of the engine, and a single-chamber dual-thrust solid rocket engine charge structure is proposed.

[0006] The technical solution of the present invention is as follows:

[0007] A single-chamber dual-thrust solid rocket engine charge structure is installed in an engine combustion chamber casing (1) and above a heat insulation layer (2), and comprises a coating layer, a booster-stage charge and an endurance-stage charge. The coating layer covers the outside of the booster-stage charge cavity and the endurance-stage charge cavity and is used to control the combustion surface of the charge column. The booster-stage charge is arranged at one end in the engine combustion chamber, close to the nozzle position, and the endurance-stage charge is arranged at the other end in the combustion chamber, away from the nozzle position. There is an air layer between the booster-stage charge and the endurance-stage charge, and there is no direct contact. Both the booster-stage charge and the endurance-stage charge can adopt a free-loading, end-burning charge column loading method with an embedded grid array structure.

[0008] Furthermore, the booster stage charge structure is embedded with a metal mesh array, which is composed of two parts: a booster stage propellant and a metal mesh array, and the metal mesh array is embedded in the booster stage propellant.

[0009] Furthermore, the booster stage propellant is fully loaded and end-burned, which can achieve the maximum loading ratio. Furthermore, the metal mesh array can be made of silver, copper, tungsten or aluminum, and the mesh array cross-section can be circular, rectangular or square.

[0010] The mesh is rectangular, parallelogram or triangular. The grid array is arranged in a single layer or multiple layers according to the diameter of the grain, so that the diameter of the grain is equally divided by the double-layer grid array. This can accelerate the transfer of gas heat from one end of the grain close to the nozzle to the other end away from the nozzle, reliably improve the burning rate of the booster stage charge, and thus increase the booster thrust.

[0011] Furthermore, the booster-stage propellant is loaded in a free-loading manner, and the booster-stage propellant is directly loaded into the combustion chamber after being embedded with the metal mesh array.

[0012] Furthermore, the booster stage propellant uses a medium / low burning rate propellant.

[0013] The endurance-level charge adopts an embedded non-metallic mesh array, which is composed of two parts: an endurance-level propellant and a non-metallic mesh array; and the non-metallic mesh array is embedded in the endurance-level propellant.

[0014] Furthermore, the cross-section of the non-metallic mesh array is circular, rectangular or diamond-shaped, the mesh opening is rectangular, parallelogram or triangular, and the mesh array is arranged in a single layer or multiple layers according to the diameter of the grain, so that the diameter of the grain is equally divided by the double-layer mesh array and pre-buried in the endurance-level propellant.

[0015] Furthermore, the mesh material can be made of carbon fiber, graphite or rubber. During the combustion of the grain, the heat of the gas is absorbed by the non-metallic mesh, which slows down the time it takes for the front propellant to reach the ignition point, thereby reducing the burning rate of the grain and meeting the requirements of low thrust and long-term operation.

[0016] Furthermore, the endurance-class propellant uses medium / low burning rate propellant, and can also be filled by wall casting.

[0017] The beneficial effects of the present invention are as follows:

[0018] The present invention constructs a single-chamber dual-thrust solid rocket engine charge structure through the organic combination of fully loaded end-burning charge and embedded grid array speed control technology, which can achieve:

[0019] (1) The booster-stage charge has an end-burning charge column embedded with a metal mesh array and selected medium / low burning rate propellants, which achieves a fully loaded charge configuration with high thrust. At the same time, it can meet the safety requirements of the engine to the greatest extent and reduce the risk of engine use.

[0020] (2) The endurance-grade charge combines a non-metallic mesh array and an end-burning charge column, which can effectively reduce the burning rate while achieving full filling and long-term operation requirements with low thrust. The mesh array structure is firm and reliable, not prone to deformation and displacement, and makes the axial heat transfer in the charge column have good consistency.

[0021] (3) Both stages of the charge use end-burning columns and grid array technology. Compared with the ordinary single-chamber dual-thrust solid rocket engine charge loading ratio of about 0.85, this charge structure can achieve a maximum loading ratio of 0.95 and can reduce the passive mass of the engine, which can effectively reduce the volume and mass of the power system and efficiently promote the development of miniaturization and lightweight of weapons and equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Attached Figure 1 A cross-sectional view of the charge structure of a single-chamber dual-thrust solid rocket engine

[0023] Attached Figure 2 Schematic diagram of the metal mesh array column embedded in the booster stage

[0024] Attached Figure 3 Schematic diagram of the endurance-class pre-buried non-metallic mesh array charge column

[0025] Among them, 1 is the combustion chamber shell; 2 is the insulation layer; 3 is the coating layer; 4 is the booster propellant; 5 is the metal mesh array; 6 is the endurance propellant; 7 is the non-metal mesh array; 8 is the nozzle seat; 9 is the convergence section; 10 is the throat liner; 11 is the expansion section; 12 is the ignition device. DETAILED DESCRIPTION

[0026] The specific implementation of the present invention is described clearly and completely below in conjunction with the accompanying drawings:

[0027] like Figure 1 to Figure 3 As shown, the present invention is a charge structure of a single-chamber dual-thrust solid rocket engine, which is mainly composed of a combustion chamber, a charge structure, a nozzle and an ignition device.

[0028] The combustion chamber is composed of a combustion chamber shell 1 and an insulation layer 2. The combustion chamber shell 1 serves as a charge space and a pressure container; the insulation layer 2 is pasted inside the combustion chamber shell 1 to isolate the high temperature of the gas and prevent the combustion chamber shell 1 from being heated and decreasing in strength; the nozzle includes a nozzle seat 8, a convergent section 9, a throat liner 10, an expansion section 11 and other components. The ignition device 12 is arranged at the position of the convergent section 9, passes through the nozzle seat 8 and the convergent section 9, and is used to ignite the initial combustion surface of the booster charge to start the engine.

[0029] A single-chamber dual-thrust solid rocket engine charge structure is installed in an engine combustion chamber casing (1) and above a heat insulation layer (2). The structure comprises a coating layer 3, a booster-stage charge 4-5 and an endurance-stage charge 6-7. The coating layer 3 covers the outside of the booster-stage charge 4-5 and the endurance-stage charge 6-7 and is used to control the combustion surface of the charge column. The booster-stage charge 4-5 is arranged at one end of the engine combustion chamber, close to the nozzle position, and the endurance-stage charge 6-7 is arranged at the other end of the combustion chamber, away from the nozzle position. There is an air layer between the booster-stage charge 4-5 and the endurance-stage charge 6-7, but there is no direct contact. The booster-stage charge 4-5 and the endurance-stage charge 6-7 can be freely loaded and loaded in an end-burning charge column with an embedded grid array structure.

[0030] The booster charge structure adopts an embedded metal mesh array 5, which is composed of two parts: a booster propellant 4 and a metal mesh array 5, and the metal mesh array 5 is embedded in the booster propellant 4. The booster propellant 4 adopts a medium / low burning rate propellant and adopts a fully filled end-burning form, which is a solid cylindrical shape and can achieve a maximum filling ratio of 0.95. The metal mesh array 5 can be made of silver, copper, tungsten or aluminum materials, and the mesh array cross-section adopts a circular, rectangular or diamond shape, and the mesh adopts a rectangular, parallelogram or triangle shape. The mesh array adopts a single-layer or multi-layer arrangement according to the diameter of the grain, so that the diameter of the grain is equally divided by the mesh array. The cross-sectional shape of the mesh array affects the radial heat transfer of the cylindrical grain. The circular cross-section has the best radial heat transfer effect and the combustion surface will be larger, while the radial heat transfer effect of the rectangular or diamond shape is relatively weak, and the radial displacement of the combustion surface is small, so that the thrust is controlled. The mesh mainly affects the axial heat transfer of the grain. Rectangles and triangles can transfer heat axially more quickly, thereby obtaining greater thrust. Parallelograms can allow the axial displacement of the combustion surface to deviate with the shape of the mesh, which can resist the lateral scouring of the gas when the engine is lateral overloaded. The arrangement of the number of mesh layers is related to the radial heat transfer effect and the diameter of the grain. If the radial heat transfer is strong and the diameter of the grain is small, a single-layer mesh array can meet the technical requirements. Otherwise, multiple layers of mesh arrays are required. The embedded metal mesh array can accelerate the transfer of gas heat from one end of the grain close to the nozzle to the other end away from the nozzle, which can reduce the time it takes for the charge far away from the nozzle to reach the ignition point, reliably increase the burning rate of the booster charge, and thus increase the booster thrust. The booster charge is loaded in a free loading manner. After the booster charge is embedded with the metal mesh array, it is directly loaded into the combustion chamber.

[0031] Among them, the structure of the endurance-level charge adopts an embedded non-metallic mesh array arrangement, which consists of two parts: the endurance-level propellant 6 and the non-metallic mesh array 7. The non-metallic mesh array 7 is embedded in the endurance-level propellant 6. According to the selected material, the non-metallic mesh array 7 can be woven, solidified or pressed, and the cross-section can be designed as a circular, rectangular or diamond cross-section. The mesh is designed to be rectangular, parallelogram or triangle. The non-metallic mesh array 7 can be arranged in a single layer or multiple layers according to the diameter of the grain, so that the diameter of the grain is equally divided by the mesh array. The material of the non-metallic mesh array 7 can be carbon fiber, graphite or rubber. During the combustion of the grain, the heat of the fuel gas is absorbed by the non-metallic mesh array 7, which slows down the time for the front propellant to reach the ignition point, thereby reducing the burning rate of the grain and meeting the requirements of low thrust and long-term operation. The endurance-level charge adopts a free filling or wall casting filling method.

[0032] The implementation principle of the present invention is: the ignition device is stimulated by the ignition current, and the ignition powder ignites the end face of the booster-stage charge close to the nozzle. When the booster-stage charge burns, the embedded metal mesh array accelerates the high temperature of the gas from one end of the charge close to the nozzle to the other end away from the nozzle, so that the temperature of the charge at the other end exceeds the ignition point faster and is ignited, the burning rate of the booster-stage charge increases significantly, and the engine thrust also increases accordingly, realizing the high-thrust boost launch requirements of weapons and equipment. After the booster stage is finished working, the endurance-stage charge is ignited by the remaining gas of the booster stage, and the endurance-stage charge whose burning rate is slowed down by the non-metallic mesh array is propelled according to the end face combustion, and after being ejected through the nozzle at an accelerated speed, a stable long-term low-thrust endurance power is generated.

[0033] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they are aware of the basic creative concepts. Therefore, the scope of protection of the present application is intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present application. Obviously, those skilled in the art may make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the protection scope of the present application and its equivalent technology, the present application is also intended to include these modifications and variations.

Claims

1. A single-chamber dual-thrust solid rocket engine charge structure, installed in the engine combustion chamber casing (1) and above the insulation layer (2), characterized in that: The charge structure consists of a coating layer (3), a booster-stage charge and an endurance-stage charge, wherein the coating layer (3) covers the outside of the booster-stage charge and the endurance-stage charge, the booster-stage charge is arranged at one end in the engine combustion chamber, close to the nozzle position, and the endurance-stage charge is arranged at the other end in the combustion chamber, away from the nozzle position, an air layer is provided between the booster-stage charge and the endurance-stage charge, and both the booster-stage charge and the endurance-stage charge adopt a propellant embedded mesh array structure and a free loading end-burning charge column method.

2. The single-chamber dual-thrust solid rocket engine charge structure according to claim 1, characterized in that: The booster-stage charge propellant is a booster-stage propellant (4), and the mesh array structure is a metal mesh array (5).

3. The single-chamber dual-thrust solid rocket engine charge structure according to claim 1, characterized in that: The booster-stage charge consists of two parts: an end-burning charge column booster-stage propellant (4) and a metal mesh array (5); the metal mesh array (5) is embedded in the booster-stage propellant (4).

4. The single-chamber dual-thrust solid rocket engine charge structure according to claim 1, characterized in that: The booster-stage propellant (4) uses a medium / low burning rate propellant in a fully filled end-burning form, and the filling ratio can reach 0.

95.

5. The single-chamber dual-thrust solid rocket engine charge structure according to claim 1, characterized in that: The metal mesh array (5) is made of silver, copper, tungsten or aluminum; the mesh array cross section can be circular, rectangular or diamond-shaped; the mesh opening can be rectangular, parallelogram or triangular, and the mesh array can be arranged in a single layer or multiple layers according to the diameter of the drug column.

6. The single-chamber dual-thrust solid rocket engine charge structure according to any one of claims 1 to 5, characterized in that: The endurance-grade charge propellant is an endurance-grade propellant (6), and the mesh array structure is a non-metallic mesh array (7) with low thermal conductivity and high heat capacity.

7. The single-chamber dual-thrust solid rocket engine charge structure according to claim 6, characterized in that: The endurance-level charge consists of two parts: an endurance-level propellant (6) and a non-metallic mesh array (7), and the non-metallic mesh array (7) is embedded in the endurance-level propellant (6).

8. The single-chamber dual-thrust solid rocket engine charge structure according to claim 6, characterized in that: The non-metallic mesh array (7) is made of carbon fiber, graphite or rubber material, and can be woven, cured or pressed according to the different materials.

9. The single-chamber dual-thrust solid rocket engine charge structure according to claim 6, characterized in that: The cross section of the non-metallic mesh array (7) can be circular, rectangular or diamond-shaped, and the mesh opening can be rectangular, parallelogram or triangular. The mesh array can be arranged in a single layer or multiple layers according to the diameter of the drug column.

10. The single-chamber dual-thrust solid rocket engine charge structure according to claim 6, characterized in that: The endurance-grade propellant (6) uses a medium / low burning rate propellant and can also be filled in a wall-attached casting manner.

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