Multi-stage self-adaptive enhanced mixing device for solid fuel ramjet engine

Abstract

The invention discloses a multistage self-adaptive enhanced mixing device for a solid fuel ramjet engine, which belongs to the technical field of solid fuel ramjet engines and comprises a front flange, a rear flange, an afterburning chamber barrel, a mixing partition plate, a heat insulating layer, a pressure measuring seat and a temperature measuring seat. The front flange and the rear flange are welded with the afterburning chamber barrel, a water pressure test is carried out after welding is completed, the mixing partition plates are bonded to the inner wall of the afterburning chamber barrel through high-temperature-resistant glue, and the mixing partition plates are distributed in a multi-stage mode, are separated through a heat insulation layer and are bonded through the high-temperature-resistant glue. In order to verify the effect of the multi-stage self-adaptive enhanced mixing device for the solid fuel ramjet engine, a pressure measuring point and a temperature measuring point are arranged on an afterburning chamber barrel and a mixing partition plate; according to the multi-stage self-adaptive enhanced mixing device, the combustion efficiency of a solid fuel ramjet can be remarkably improved, and the efficiency is further improved along with the increase of the number of the mixing partition plates.

Description

Technical Field

[0001] The invention relates to the technical field of solid fuel ramjet engines, and in particular to a multi-stage adaptive enhanced mixing device for solid fuel ramjet engines. Background Art

[0002] In recent years, supersonic vehicles have gradually attracted the attention of experts and scholars at home and abroad due to their potential military and civilian value. For supersonic vehicles, it is very important to choose a suitable engine. Solid fuel ramjet engines do not need to carry oxidizers, but only rely on oxygen in the air to react with the solid fuel they carry, so they have extremely high specific impulse (usually more than 10,000 N·s / kg), which is 3 to 4 times that of solid rocket engines. In addition, they are low in cost and simple in structure, making them ideal power devices for supersonic vehicles.

[0003] The working core of a solid fuel ramjet is a ducted combustion chamber containing solid fuel in a tubular structure. During operation, the solid fuel ramjet absorbs and stagnates incoming air through the air inlet, increases the air temperature and pressure, and flows through the inner hole of the tubular fuel, where it diffuses and burns with the fuel pyrolysis gas in the boundary layer. Unlike solid rocket engines, the oxygen in the air can mix with the fuel in the tubular channel and undergo a combustion reaction, which means that the solid fuel ramjet does not need to carry any oxidizer and has better engine performance.

[0004] However, calculations based on turbulent boundary layer theory show that at the combustion chamber outlet, only about 50% of the fuel can be fully mixed and burned, resulting in low engine combustion efficiency. This is because the diffusion combustion method in solid fuel ramjet engines results in a low mixing rate between the fuel and the oxidizer. In addition, due to the high air flow velocity and limited space in the combustion chamber, the fuel stays in the combustion chamber for a short time, further reducing the degree of mixing between the fuel and the air. These factors lead to difficulties in organizing the combustion of solid fuel ramjet engines, which in turn reduces their working performance. Therefore, how to effectively organize the mixed combustion of fuel and air is of great significance to improving the overall performance of the engine.

[0005] As the main place for fuel combustion and energy release in solid fuel ramjet engines, the structure of the afterburner plays a decisive role in the overall performance of the engine. In practical applications, incompletely burned primary fuel gas will enter the afterburner for secondary combustion. Considering that the fuel gas stays in the afterburner for a very short time, achieving efficient secondary combustion in a short time is an important development direction. Since the diffusion rate of fuel and air mixing has an important influence on the combustion process, it is necessary to study how to enhance the mixing of fuel and air.

[0006] Therefore, a multi-stage adaptive enhanced mixing device for solid fuel ramjet engines is proposed to improve the combustion efficiency and overall performance of solid fuel ramjet engines. Summary of the invention

[0007] The present invention is intended to provide a multi-stage adaptive enhanced mixing device for a solid fuel ramjet engine to solve the problems raised in the above background technology.

[0008] In order to achieve the above object, the present invention provides the following technical solutions:

[0009] A multi-stage adaptive enhanced mixing device for a solid fuel ramjet engine, comprising a front flange, a rear flange, a secondary combustion chamber cylinder, a mixing baffle, a heat insulation layer, a pressure measuring seat and a temperature measuring seat;

[0010] The front flange is welded to the front end of the afterburning chamber cylinder, and the rear flange is welded to the rear end of the afterburning chamber cylinder;

[0011] A plurality of mixing partitions and a heat insulating layer are bonded to the inner wall of the afterburning chamber cylinder, the mixing partitions are distributed in multiple stages, the multiple stages of mixing partitions are separated by a heat insulating layer, and the mixing partitions and the heat insulating layer are bonded;

[0012] The combustion chamber cylinder and the insulation layer are both provided with measuring point holes, which are evenly distributed along the circumference of the central axis, and there are four measuring point holes in number; the measuring point holes are divided into pressure test holes and temperature test holes, which are arranged in groups of two and symmetrically distributed; when the combustion chamber cylinder and the insulation layer are assembled, they are aligned according to the pressure test holes and the temperature test holes, and the outer wall of the combustion chamber cylinder is provided with a pressure measuring seat and a temperature measuring seat at the pressure test holes and the temperature test holes, respectively.

[0013] Preferably, the mixing baffle is an annular baffle structure, and the distribution of the mixing baffle starts from the front end of the afterburning chamber cylinder, and the remaining mixing plates are distributed in the afterburning chamber at certain intervals through the insulation layer. A docking groove is required to be opened at the tail of the insulation layer at the tail end of the afterburning chamber cylinder, and a boss is provided on the inner wall of the afterburning chamber cylinder at the rear end, and the docking groove can cooperate with the boss for docking.

[0014] Preferably, the mixing baffles are bonded to the inner wall of the afterburning chamber cylinder by means of high temperature resistant adhesive, the mixing baffles are separated by an insulating layer, and the joints between the mixing baffles and the insulating layer are bonded by means of high temperature resistant adhesive.

[0015] Preferably, the mixing partitions are matched in corresponding quantity and size according to actual needs.

[0016] Preferably, the afterburning chamber cylinder and the insulation layer are both provided with measuring point holes which can be distributed in several groups along the axial array.

[0017] Preferably, the pressure measuring seats and temperature measuring seats can be arranged in several groups along the measuring point holes.

[0018] Preferably, the mixed separator is made of high-strength graphite material.

[0019] Preferably, the thermal insulation layer is made of high-strength graphite material.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. Improve mixing and combustion efficiency: Through the multi-stage mixing baffle structure, the primary gas and air are effectively mixed, which significantly improves the combustion efficiency;

[0022] 2. Enhanced combustion stability: Multi-stage mixing baffles generate complex multi-vortex motion, stabilize the combustion process, reduce combustion oscillation and instability, and ensure reliable operation of the engine under various operating conditions;

[0023] 3. Increase thrust and specific impulse: Optimize the mixing and combustion process, and the multi-stage mixing baffle structure significantly improves the engine thrust and specific impulse, and enhances the engine's working efficiency and performance indicators;

[0024] 4. Optimize the flow field in the combustion chamber: The mixing baffle controls and guides the airflow, optimizes the flow field distribution in the combustion chamber, reduces flow separation and local hot spots, and improves the overall combustion performance;

[0025] 5. Simplify design and achieve the best effect: The design of multi-stage mixing baffles is relatively simple, and the best flow field control and combustion effect can be achieved through reasonable arrangement;

[0026] 6. Heat management and extended service life: Multi-stage mixing baffles effectively disperse and manage heat, reduce the heat load of the combustion chamber and nozzle, and extend the service life of the engine;

[0027] 7. Flexible adjustment of performance parameters: By adjusting the number and spacing of mixing baffles, the engine performance parameters can be flexibly adjusted to meet different mission requirements and working conditions;

[0028] 8. Easy maintenance and replacement: The structure is relatively simple, and the multi-stage mixing partitions are easy to maintain and replace, reducing maintenance costs and time. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the overall structure of a multi-stage adaptive enhanced mixing device for a solid fuel ramjet engine;

[0030] Figure 2 It is a cross-sectional view of the overall structure of a multi-stage adaptive enhanced mixing device for a solid fuel ramjet engine;

[0031] Figure 3A schematic diagram of a mixing baffle structure of a multi-stage adaptive enhanced mixing device for a solid fuel ramjet engine;

[0032] Figure 4 A schematic diagram of a mixing baffle of the last stage of a multi-stage adaptive enhanced mixing device for a solid fuel ramjet engine;

[0033] Figure 5 Schematic diagram of the effect of the number of baffles on combustion efficiency in a multi-stage adaptive enhanced mixing device.

[0034] The reference numerals in the drawings of the specification include:

[0035] 1. Front flange; 2. Rear flange; 3. Afterburning chamber cylinder; 301. Boss; 4. Mixing baffle; 5. Insulation layer; 501. Docking groove; 6. Temperature measuring seat; 601. Temperature test hole; 7. Pressure measuring seat; 701. Pressure test hole. DETAILED DESCRIPTION

[0036] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments:

[0037] like Figure 1-4 As shown, a multi-stage adaptive enhanced mixing device for a solid fuel ramjet engine comprises a front flange 1, a rear flange 2, a secondary combustion chamber cylinder 3, a mixing baffle 4, an insulation layer 5, a pressure measuring seat 7 and a temperature measuring seat 6;

[0038] The front flange 1 is welded to the front end of the afterburning chamber cylinder 3, and the rear flange 2 is welded to the rear end of the afterburning chamber cylinder 3;

[0039] A plurality of mixing partitions 4 and a heat insulating layer 5 are bonded to the inner wall of the afterburning chamber cylinder 3. The mixing partitions 4 are distributed in multiple stages. The multiple stages of mixing partitions 4 are separated by the heat insulating layer 5. The mixing partitions 4 and the heat insulating layer 5 are bonded.

[0040] Both the combustion chamber cylinder 3 and the insulation layer 5 are provided with measuring point holes, which are evenly distributed along the circumference of the central axis, and there are four measuring point holes in total; the measuring point holes are divided into pressure test holes 701 and temperature test holes 601, which are arranged in groups of two and symmetrically distributed; when the combustion chamber cylinder 3 and the insulation layer 5 are assembled, they are aligned according to the pressure test holes 701 and the temperature test holes 601, and the outer wall of the combustion chamber cylinder 3 is provided with a pressure measuring seat 7 and a temperature measuring seat 6 at the pressure test holes 701 and the temperature test holes 601, respectively.

[0041] The mixing baffle 4 is an annular baffle structure. The distribution of the mixing baffle 4 starts from the front end of the afterburning chamber cylinder 3. The remaining mixing plates are distributed in the afterburning chamber at a certain interval through the insulation layer 5. A docking groove 501 needs to be opened at the tail of the insulation layer 5 at the tail end of the afterburning chamber cylinder 3. The inner wall of the afterburning chamber cylinder 3 is provided with a boss 301 at the rear end, and the docking groove 501 can be docked with the boss 301; the mixing baffle 4 is made of high-strength graphite material.

[0042] The mixing baffles 4 are bonded to the inner wall of the afterburning chamber cylinder 3 by means of high temperature resistant adhesive, the mixing baffles 4 are separated by the insulation layer 5, and the joints between the mixing baffles 4 and the insulation layer 5 are bonded by means of high temperature resistant adhesive.

[0043] The mixing baffles 4 are matched with corresponding quantity and size according to actual needs, so as to realize multi-stage adaptive mixing enhancement of fuel and air by the baffles and improve combustion efficiency.

[0044] Both the afterburning chamber cylinder 3 and the heat insulation layer 5 are provided with measuring point holes which can be distributed in several groups along the axial array.

[0045] The pressure measuring seats 7 and the temperature measuring seats 6 can be arranged in several groups along the measuring point holes.

[0046] The specific implementation process is as follows:

[0047] A working method of a multi-stage adaptive enhanced mixing device for a solid fuel ramjet engine is as follows: the incompletely burned primary gas from the combustion chamber flows into the multi-stage adaptive enhanced mixing device at a subsonic speed. Each time the primary gas passes through the first-stage mixing baffle 4, the speed of the primary gas will be reduced. The mixing baffle 4 structure will increase the residence time of the primary gas in the engine, making the combustion of the primary gas and the oxygen in the atmosphere more complete; the mixing baffle 4 also causes the flow field to produce complex multi-vortex motion, stabilize the combustion process, reduce combustion oscillation and instability, and ensure the reliable operation of the engine under various working conditions; the mixing baffle 4 effectively controls and guides the airflow, optimizes the flow field distribution in the afterburning chamber, reduces flow separation and local hot spots, and improves the overall combustion performance. Due to the above effects of the mixing baffle 4, the primary gas further undergoes secondary reactions and fully burns in the multi-stage adaptive enhanced mixing device, and finally expands and accelerates to be discharged through the nozzle, generating thrust and improving performance.

[0048] The mixing partition 4 is made of high-strength graphite material. The high-strength graphite material has the characteristics of high melting point and resistance to burning, and has the ability to resist high temperature and high-temperature airflow erosion.

[0049] like Figure 5As shown, an experiment was conducted on the effect of the number of mixing baffles 4 in the multi-stage adaptive enhanced mixing device on the engine combustion efficiency. The multi-stage adaptive enhanced mixing device can significantly improve the combustion efficiency of the solid fuel ramjet engine. As the number of mixing baffles 4 increases, the efficiency is also improved more.

[0050] The above is only an embodiment of the present invention, and the common knowledge such as the known specific technical solutions and / or characteristics in the solution is not described in detail here. It should be pointed out that for those skilled in the art, without departing from the technical solution of the present invention, several modifications and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A multi-stage adaptive enhanced mixing device for a solid fuel ramjet engine, characterized in that: It comprises a front flange (1), a rear flange (2), a combustion chamber cylinder (3), a mixing baffle (4), a heat insulating layer (5), a pressure measuring seat (7) and a temperature measuring seat (6); The front flange (1) is welded to the front end of the afterburning chamber cylinder (3), and the rear flange (2) is welded to the rear end of the afterburning chamber cylinder (3); A plurality of mixing partitions (4) and a heat insulating layer (5) are bonded to the inner wall of the afterburning chamber cylinder (3); the mixing partitions (4) are distributed in multiple stages, the multiple stages of mixing partitions (4) are separated by the heat insulating layer (5), and the mixing partitions (4) and the heat insulating layer (5) are bonded; The combustion chamber cylinder (3) and the insulation layer (5) are both provided with measuring point holes, and the measuring point holes are evenly distributed along the circumference of the central axis, and the number is four; the measuring point holes are divided into pressure test holes (701) and temperature test holes (601), which are arranged in groups of two and symmetrically distributed; when the combustion chamber cylinder (3) and the insulation layer (5) are assembled, they are aligned according to the pressure test holes (701) and the temperature test holes (601), and the outer wall of the combustion chamber cylinder (3) is respectively provided with a pressure measuring seat (7) and a temperature measuring seat (6) at the pressure test holes (701) and the temperature test holes (601).

2. A multi-stage adaptive enhanced mixing device for a solid fuel ramjet engine according to claim 1, characterized in that: The mixing baffle (4) is an annular baffle structure. The distribution of the mixing baffle (4) starts from the front end of the afterburning chamber cylinder (3). The remaining mixing baffles are distributed in the afterburning chamber at a certain interval through the insulation layer (5). A docking groove (501) is required to be provided at the tail end of the insulation layer (5) at the tail end of the afterburning chamber cylinder (3). A boss (301) is provided on the inner wall of the afterburning chamber cylinder (3) at the rear end. The docking groove (501) can be docked with the boss (301).

3. The multi-stage adaptive enhanced mixing device for a solid fuel ramjet engine according to claim 1, characterized in that: The mixing baffles (4) are bonded to the inner wall of the afterburning chamber cylinder (3) by means of high temperature resistant adhesive, the mixing baffles (4) are separated by the insulation layer (5), and the joints between the mixing baffles (4) and the insulation layer (5) are bonded by means of high temperature resistant adhesive.

4. According to claim 3, a multi-stage adaptive enhanced mixing device for a solid fuel ramjet engine is characterized in that: The mixing partitions (4) are matched in number and size according to actual needs.

5. The multi-stage adaptive enhanced mixing device for a solid fuel ramjet engine according to claim 1, characterized in that: The afterburning chamber cylinder (3) and the heat insulation layer (5) are both provided with measuring point holes which can be distributed in a plurality of groups along the axial array.

6. A multi-stage adaptive enhanced mixing device for a solid fuel ramjet engine according to claim 5, characterized in that: The pressure measuring seats (7) and temperature measuring seats (6) can be arranged in several groups along the measuring point holes.

7. A multi-stage adaptive enhanced mixing device for a solid fuel ramjet engine according to any one of claims 1 to 3, characterized in that: The mixed partition (4) and the heat insulating layer (5) are made of high-strength graphite material.

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