A multi-stage self-adapting augmented mixing device for solid fuel ramjet engines

Abstract

This invention discloses a multi-stage adaptive enhanced blending device for solid-fuel ramjet engines, belonging to the technical field of solid-fuel ramjet engines. It includes a front flange, a rear flange, a combustion chamber shell, blending baffles, an insulation layer, a pressure measuring seat, and a temperature measuring seat. The front and rear flanges are welded to the combustion chamber shell, and a hydrostatic test is performed after welding. The blending baffles are bonded to the inner wall of the combustion chamber shell with high-temperature resistant adhesive. The blending baffles are multi-stage, separated by the insulation layer and bonded together with high-temperature resistant adhesive. To verify the effectiveness of the multi-stage adaptive enhanced blending device for solid-fuel ramjet engines, pressure and temperature measuring points are set on the combustion chamber shell and the blending baffles. The multi-stage adaptive enhanced blending device provided by this invention can significantly improve the combustion efficiency of solid-fuel ramjet engines; the efficiency increases further with the increase in the number of blending baffles.

Description

Technical Field

[0001] This invention relates to the field of solid fuel ramjet engine technology, and more particularly to a multi-stage adaptive enhanced mixing device for solid fuel ramjet engines. Background Technology

[0002] In recent years, supersonic vehicles have gradually attracted the attention of experts and scholars both domestically and internationally due to their potential military and civilian value. For supersonic vehicles, selecting a suitable engine is crucial. Solid-fuel ramjet engines, because they do not require an oxidizer and rely solely on the combustion reaction between oxygen in the air and their own solid fuel, possess extremely high specific impulse (typically above 10,000 N·s / kg), which is 3 to 4 times that of solid rocket engines. Furthermore, they are inexpensive and have a simple structure, making them an ideal power source for supersonic vehicles.

[0003] The core of a solid-fuel ramjet engine is a tubular combustion chamber containing tubular solid fuel. During operation, the ramjet draws in and impounds incoming air through the intake duct, increasing its temperature and pressure before it flows through the tubular fuel's internal pores, where it diffuses and combusts with the fuel's pyrolysis gases in the boundary layer. Unlike solid rocket engines, oxygen in the air can mix with the fuel and undergo combustion within the tubular channel, eliminating the need for an oxidizer and resulting in superior engine performance.

[0004] However, calculations based on turbulent boundary layer theory show that only about 50% of the fuel is fully mixed and burned at the combustion chamber outlet, resulting in low engine combustion efficiency. This is because the diffusion combustion mode in solid-fuel ramjet engines leads to a low mixing rate between fuel and oxidizer. Furthermore, the high airflow velocity, limited space within the combustion chamber, and short fuel residence time further reduce fuel-air mixing. These factors make combustion organization difficult in solid-fuel ramjet engines, thus reducing their performance. Therefore, effectively organizing fuel-air mixing and combustion is crucial for improving overall engine performance.

[0005] The afterburner, as the primary site for fuel combustion and energy release in a solid-fuel ramjet engine, plays a decisive role in the engine's overall performance. In practical applications, incompletely combusted primary combustion gases enter the afterburner for secondary combustion. Considering the extremely short residence time of the combustion gases in the afterburner, achieving efficient secondary combustion within a short time is an important development direction. Since the fuel-air mixing and diffusion rate has a significant impact on the combustion process, researching ways to enhance the mixing of combustion gases and air is of great necessity.

[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 aims to provide a multi-stage adaptive enhanced mixing device for solid fuel ramjet engines to solve the problems mentioned in the background art.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

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

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

[0011] The inner wall of the combustion chamber cylinder is bonded with several blending baffles and an insulation layer. The blending baffles are distributed in multiple levels and are separated by the insulation layer. The blending baffles and the insulation layer are bonded together.

[0012] Both the combustion chamber shell and the insulation layer are provided with measuring holes, which are evenly distributed along the central axis circumference, with a total of four measuring holes. The measuring holes are divided into pressure test holes and temperature test holes, which are arranged in pairs and symmetrically distributed. When the combustion chamber shell and the insulation layer are assembled, they are aligned according to the pressure test holes and temperature test holes. Pressure measuring seats and temperature measuring seats are respectively provided on the outer wall of the combustion chamber shell at the pressure test holes and temperature test holes.

[0013] Preferably, the blending baffle is an annular baffle structure. The distribution of the blending baffle starts at the front end of the combustion chamber cylinder and is attached to the end of the combustion chamber. The remaining blending baffles are distributed at certain intervals in the combustion chamber through the insulation layer. A docking groove needs to be opened at the end of the insulation layer at the end of the combustion chamber cylinder. A boss is provided on the inner wall of the combustion chamber cylinder at the rear end. The docking groove can be engaged with the boss.

[0014] Preferably, the blending baffles are bonded to the inner wall of the combustion chamber cylinder with high-temperature resistant adhesive, the blending baffles are separated by an insulation layer, and the joint between the blending baffles and the insulation layer is bonded with high-temperature resistant adhesive.

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

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

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

[0018] Preferably, the blended partition is made of high-strength graphite material.

[0019] Preferably, the insulation layer is a high-strength graphite material.

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

[0021] 1. Improved mixing and combustion efficiency: Through a multi-stage mixing baffle structure, primary fuel gas and air are effectively mixed, significantly improving combustion efficiency;

[0022] 2. Enhanced combustion stability: The multi-stage mixing baffle generates complex multi-vortex motion, which stabilizes the combustion process, reduces combustion oscillations and instabilities, and ensures reliable engine operation under various operating conditions;

[0023] 3. Increase thrust and specific impulse: Optimize the mixing and combustion process, and the multi-stage blending baffle structure significantly improves engine thrust and specific impulse, enhancing engine 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 overall combustion performance;

[0025] 5. Simplified design and optimal performance: The multi-stage mixing baffle design is relatively simple, and optimal flow field control and combustion effect can be achieved through reasonable arrangement;

[0026] 6. Thermal Management and Extended Service Life: Multi-stage blending baffles effectively disperse and manage heat, reducing the thermal load on the combustion chamber and nozzle, and extending engine service life;

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

[0028] 8. Easy maintenance and replacement: The structure is relatively simple, and the multi-stage mixing baffle is easy to maintain and replace, reducing maintenance costs and time. Attached Figure Description

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

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

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

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

[0033] Figure 5 This is a schematic diagram showing the effect of the number of baffles on combustion efficiency in a multi-stage adaptive enhanced blending device.

[0034] The reference numerals in the accompanying drawings include:

[0035] 1. Front flange; 2. Rear flange; 3. Afterburner chamber shell; 301. Boss; 4. Mixing baffle; 5. Insulation layer; 501. Butt groove; 6. Temperature measuring seat; 601. Temperature test hole; 7. Pressure measuring seat; 701. Pressure test hole. Detailed Implementation

[0036] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments:

[0037] like Figure 1-4 As shown, a multi-stage adaptive enhanced blending device for a solid fuel ramjet engine includes a front flange 1, a rear flange 2, a combustion chamber cylinder 3, a blending 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 combustion chamber cylinder 3, and the rear flange 2 is welded to the rear end of the combustion chamber cylinder 3.

[0039] Several blending baffles 4 and a heat insulation layer 5 are bonded to the inner wall of the combustion chamber cylinder 3. The blending baffles 4 are distributed in multiple stages, and the multiple stages of blending baffles 4 are separated by the heat insulation layer 5. The blending baffles 4 and the heat insulation layer 5 are bonded together.

[0040] Both the combustion chamber shell 3 and the insulation layer 5 are provided with measuring point holes, which are evenly distributed along the central axis circumference, with a total of four holes. The measuring point holes are divided into pressure test holes 701 and temperature test holes 601, which are arranged in pairs and symmetrically distributed. When the combustion chamber shell 3 and the insulation layer 5 are assembled, they are aligned with the pressure test holes 701 and the temperature test holes 601. Pressure measuring seat 7 and temperature measuring seat 6 are respectively provided on the outer wall of the combustion chamber shell 3 at the pressure test holes 701 and the temperature test holes 601.

[0041] The blending baffle 4 is an annular baffle structure. The distribution of the blending baffle 4 starts at the front end of the combustion chamber cylinder 3. The remaining blending baffles are distributed at certain intervals in the combustion chamber through the insulation layer 5. The insulation layer 5 at the rear end of the combustion chamber cylinder 3 needs to have a docking groove 501. The inner wall of the combustion chamber cylinder 3 is provided with a boss 301 at the rear end. The docking groove 501 can be connected with the boss 301. The blending baffle 4 is made of high-strength graphite material.

[0042] The mixing partition 4 is bonded to the inner wall of the combustion chamber cylinder 3 with high-temperature resistant adhesive. The mixing partitions 4 are separated by a heat insulation layer 5, and the joint between the mixing partition 4 and the heat insulation layer 5 is bonded with high-temperature resistant adhesive.

[0043] The number and size of the blending baffles 4 are matched according to actual needs, thereby realizing the multi-stage adaptive blending enhancement of fuel and air by the baffles and improving combustion efficiency.

[0044] Both the combustion chamber cylinder 3 and the insulation layer 5 are provided with measuring point holes, which can be arranged in several groups along the axial direction.

[0045] Several sets of pressure measuring base 7 and temperature measuring base 6 can be set along the measuring point holes.

[0046] The specific implementation process is as follows:

[0047] A multi-stage adaptive enhanced blending device for a solid-fuel ramjet engine operates as follows: Unburned primary combustion gas from the combustion chamber flows into the multi-stage adaptive enhanced blending device at subsonic speed. Each time the primary combustion gas passes through a first-stage blending baffle 4, its velocity decreases. The structure of the blending baffle 4 increases the residence time of the primary combustion gas within the engine, resulting in more complete combustion with atmospheric oxygen. The blending baffle 4 also induces complex multi-vortex motion in the flow field, stabilizing the combustion process, reducing combustion oscillations and instabilities, and ensuring reliable engine operation under various conditions. The blending baffle 4 effectively controls and guides airflow, optimizing the flow field distribution within the afterburner, reducing flow separation and localized hot spots, and improving overall combustion performance. Due to the above effects of the blending baffle 4, the primary combustion gas undergoes further secondary reaction and complete combustion within the multi-stage adaptive enhanced blending device, finally expanding and accelerating before being discharged through the nozzle, generating thrust and improving performance.

[0048] The blended partition 4 is made of high-strength graphite material, which has the characteristics of high melting point and resistance to burn-off, and has the ability to withstand high temperature and high temperature airflow erosion.

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

[0050] The above descriptions are merely embodiments of the present invention, and common knowledge such as specific technical solutions and / or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solutions of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A multi-stage adaptive enhanced blending device for a solid fuel ramjet engine, characterized in that: It includes a front flange (1), a rear flange (2), a combustion chamber cylinder (3), a mixing baffle (4), an insulation 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 combustion chamber cylinder (3), and the rear flange (2) is welded to the rear end of the combustion chamber cylinder (3). The inner wall of the combustion chamber cylinder (3) is bonded with several blending baffles (4) and a heat insulation layer (5). The blending baffles (4) are distributed in multiple levels. The multiple levels of blending baffles (4) are separated by the heat insulation layer (5). The blending baffles (4) and the heat insulation layer (5) are bonded together. Both the combustion chamber cylinder (3) and the insulation layer (5) are provided with measuring holes. The measuring holes are evenly distributed along the central axis circumference, and there are four measuring holes. The measuring holes are divided into pressure test holes (701) and temperature test holes (601), which are arranged in pairs 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 temperature test holes (601). Pressure measuring seats (7) and temperature measuring seats (6) are respectively provided on the outer wall of the combustion chamber cylinder (3) at the pressure test holes (701) and temperature test holes (601).

2. The multi-stage adaptive enhanced blending device for a solid fuel ramjet engine according to claim 1, characterized in that: The mixing partition (4) is an annular partition structure. The distribution of the mixing partition (4) starts at the front end of the combustion chamber cylinder (3) and the remaining mixing partitions are distributed in the combustion chamber at certain intervals through the insulation layer (5). The insulation layer (5) at the rear end of the combustion chamber cylinder (3) needs to be provided with a docking groove (501). The inner wall of the combustion chamber cylinder (3) is provided with a boss (301) at the rear end. The docking groove (501) can be connected with the boss (301).

3. A multi-stage adaptive enhanced blending device for a solid fuel ramjet engine according to claim 1, characterized in that: The mixing partition (4) is bonded to the inner wall of the combustion chamber cylinder (3) with high temperature resistant adhesive. The mixing partitions (4) are separated by a heat insulation layer (5). The joint between the mixing partition (4) and the heat insulation layer (5) is bonded with high temperature resistant adhesive.

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

5. A multi-stage adaptive enhanced blending device for a solid fuel ramjet engine according to claim 1, characterized in that: Both the combustion chamber cylinder (3) and the insulation layer (5) are provided with measuring point holes, which can be arranged in several groups along the axial direction.

6. A multi-stage adaptive enhanced blending device for a solid fuel ramjet engine according to claim 5, characterized in that: Several sets of pressure measuring base (7) and temperature measuring base (6) can be set along the measuring point holes.

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

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