A vortex control stabilizer

Abstract

The invention discloses a vortex control stabilizer, comprising an air inlet nozzle, an oil injection pipe, an evaporation pipe, a U-shaped gradually expanding blunt body and a stabilizer wall surface, wherein the U-shaped gradually expanding blunt body is formed of a closed cavity by an arc-shaped front wall, a gradually expanding side wall and a rear end wall, the evaporation pipe is connected to the rear end wall, the evaporation pipe is provided with a plurality of nozzles leading to the area between the stabilizer wall surfaces, the air inlet nozzle is provided with a plurality of nozzles and is discretely arranged along the circumference of the vortex control stabilizer, the air inlet nozzle extends from the arc-shaped front wall into the closed cavity and is connected to the evaporation pipe, the oil injection pipe is connected to the air inlet nozzle from the side of the air inlet nozzle, the stabilizer wall surface comprises an inner wall surface and an outer wall surface, the inner wall surface and the outer wall surface are respectively located at the inner and outer edges of the rear end wall, an air inlet gap is left between the inner wall surface and the inner edge of the rear end wall, the inner wall surface is provided with a guide plate extending to the outer wall surface, an air inlet gap is formed between the guide plate and the rear end wall and is connected to the air inlet gap. The invention can achieve stable and efficient combustion in a wide range of working conditions, and improve the ignition and flameout performance and combustion efficiency.

Description

Technical Field

[0001] The invention relates to a vortex control stabilizer, belonging to the technical field of flame stabilization devices. Background Art

[0002] The afterburner of an aircraft engine is generally located after the turbine. The exhaust gas after combustion in the main combustion chamber enters the afterburner after expansion through the turbine. The exhaust gas entering the afterburner after expansion through the turbine has the following characteristics: 1) The total inlet pressure is low, the ignition conditions become worse, it is difficult to burn stably, and the combustion efficiency is reduced; 2) The intake speed is high, ignition is difficult, and the flame combustion is unstable; 3) The intake oxygen content is low, which is not conducive to ignition, combustion efficiency, and flame stability; 4) The intake temperature is high, which is conducive to ignition and combustion.

[0003] Based on the above characteristics of the air intake into the afterburner, how to achieve flame-stabilized combustion has become a key issue. The most common afterburner is the V-type stabilizer. When the airflow flows through the stabilizer at a certain speed, due to the effect of viscosity, the gas in the hidden area behind the stabilizer is sucked in and forms a low-pressure area. When the airflow flows through the tail of this area, a part of the fluid flows into the hidden area at a speed opposite to the mainstream, thereby forming two roughly symmetrical vortices, namely the reflow zone. However, the V-type stabilizer has the problem of narrow flame stabilization range and low combustion efficiency. The existing technology is to introduce mainstream air by opening a gap in the wall of the stabilizer to form a single vortex flow structure to improve the stabilization effect. At present, the flame stabilizer with a slit on the wall has the following technical defects: 1) The distance between the oil pipeline and the baffle and the fuel outlet slit inside the flame stabilizer is relatively close, and the mixing efficiency of fuel and air is low. 2) The outlet slits of the evaporator are distributed in a rectangular radial pattern, and the slits are on the same side as the side wall slits, which is not conducive to the fuel entering the stabilizer. 3) At higher airflow velocities, the vortex center in the recirculation zone of the flame stabilizer with slits on the side wall will gradually move backwards, which is not conducive to the stability of the flame. 4) If only the wall is slit, small vortices will be formed in the small triangles on the upper and lower sides of the stabilizer. On the one hand, it is easy to affect the formation of large-scale vortices at the rear. On the other hand, the high-temperature gas flowing back from the rear will increase the thermal stress on the evaporator, which is easy to cause damage to the device. Summary of the invention

[0004] In view of the above-mentioned defects in the prior art, the task of the present invention is to provide a vortex-controlled stabilizer to solve the problem that the stabilizer is easily affected by the high-speed main airflow, resulting in a narrow range of flame stabilization conditions, and the problem of low combustion efficiency.

[0005] The technical solution of the present invention is as follows: a vortex-controlled stabilizer, the vortex-controlled stabilizer includes an air inlet nozzle, an oil injection pipe, an evaporator pipe, a U-shaped gradually expanding blunt body and a stabilizer wall surface, the U-shaped gradually expanding blunt body is formed by an arc-shaped front wall, a gradually expanding side wall and a rear end wall to form a closed cavity, the evaporator pipe is connected to the rear end wall, the evaporator pipe is provided with a plurality of nozzles leading to the area between the stabilizer wall surfaces, the air inlet nozzle is provided with a plurality of nozzles and is discretely arranged along the circumferential direction of the vortex-controlled stabilizer, the air inlet nozzle extends from the arc-shaped front wall into the U-shaped The closed cavity of the gradually expanding blunt body is communicated with the evaporator tube, the fuel injection pipe is communicated with the air intake nozzle from the side of the air intake nozzle, the stabilizer wall surface includes an inner wall surface and an outer wall surface, the inner wall surface and the outer wall surface are respectively located at the inner and outer edges of the rear end wall of the U-shaped gradually expanding blunt body, an air intake gap is left between the inner wall surface and the inner edge of the rear end wall, the inner wall surface is provided with a guide plate extending toward the outer wall surface, an air intake gap is formed between the guide plate and the rear end wall, and the air intake gap is communicated with the air intake gap.

[0006] The present invention mixes oil and gas through the front air intake nozzle and the fuel injection pipe, and uses the heat of the burned gas in combination with the evaporation pipe to accelerate the evaporation and mixing process, shorten the time and length of the mixed gas formation, strengthen the fuel atomization, evaporation and mixing effects, improve the oil and gas mixing degree, and strengthen the combustion process. By forming an air intake gap between the inner wall and the U-shaped gradually expanding blunt body, a part of the airflow inside the stabilizer is introduced into the vortex-controlled stabilizer, and a large-scale stable single vortex flow structure is formed in conjunction with the jet of the evaporation pipe. The single vortex flow structure is protected by the small-scale secondary vortex formed by the stabilizer wall and the rear of the inner wall of the stabilizer, and is insensitive to changes in airflow velocity. The large-scale single vortex flow structure can further achieve that the airflow velocity in the wall boundary layer is always less than the flame propagation velocity, thereby achieving stable combustion of the flame.

[0007] Furthermore, in order to improve the atomization effect of the fuel in the air intake nozzle, improve the mixing effect with the airflow before entering the evaporator tube, and accelerate the gasification and mixing in the evaporator tube, an oil splash plate is provided at the outlet of the oil injection pipe in the air intake nozzle, and a gap is left between the oil splash plate and the outlet of the oil injection pipe.

[0008] Furthermore, the evaporation tube is embedded in the rear end wall, and the nozzle is arranged toward the outer wall surface.

[0009] Furthermore, the diameter of the fuel injection port formed by the fuel injection pipe being connected to the air intake nozzle is 1 to 5 mm.

[0010] Furthermore, the nozzle diameter of the evaporation tube is 1 to 5 mm.

[0011] Furthermore, the included angle of the gradually diverging side wall of the U-shaped gradually diverging blunt body is 20-40°.

[0012] Furthermore, the distance between the inner wall surface of the vortex control stabilizer and the outer wall surface is 20 to 70 mm.

[0013] Furthermore, the distance between the inner wall surface and the inner edge of the rear end wall is 2 to 8 mm.

[0014] Furthermore, the distance between the guide plate and the rear end wall is 2 to 8 mm.

[0015] Furthermore, the height of the guide plate is 5 to 30 mm.

[0016] The advantages of the present invention compared with the prior art are:

[0017] A stable large-scale single vortex flow structure is formed inside the vortex-controlled stabilizer. This large-scale single vortex flow structure is insensitive to changes in airflow velocity due to the protection of the stabilizer wall and the small-scale secondary vortex flow structure, achieving ignition and flame stability at high incoming flow velocities. Compared with conventional V-type stabilizers, it achieves stable and efficient combustion in a wider range of operating conditions with less added weight. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the three-dimensional structure of the vortex-controlled stabilizer of the present invention (partial sectioning and removal).

[0019] Figure 2 It is a three-dimensional schematic diagram of a unit structure of the vortex-controlled stabilizer of the present invention.

[0020] Figure 3 It is a left schematic diagram of a unit structure of the vortex-controlled stabilizer of the present invention.

[0021] Figure 4 It is a right side schematic diagram of a unit structure of the vortex control stabilizer of the present invention.

[0022] Figure 5 It is a schematic top view of a unit structure of the vortex-controlled stabilizer of the present invention.

[0023] Figure 6 for Figure 5 AA section diagram of .

[0024] Figure 7 This is a working principle diagram of the invented vortex-controlled stabilizer. DETAILED DESCRIPTION

[0025] The present invention will be further described below in conjunction with the embodiments, but are not intended to limit the present invention.

[0026] Please combine Figure 1 and Figure 2As shown, the vortex control stabilizer involved in the embodiment of the present invention is an annular structure as a whole, which includes an air inlet nozzle 1, an oil injection pipe 2, an evaporator pipe 3, a U-shaped gradually expanding blunt body 4 and a stabilizer wall surface, and the stabilizer wall surface includes an inner wall surface 5 and an outer wall surface 6 both of which are annular. The inner wall surface 5 is a wall surface located in the inner circle of the annular structure, and the outer wall surface 6 is a wall surface located in the outer circle of the annular structure. The stabilizer wall surface is connected to the rear end of the U-shaped gradually expanding blunt body 4, and together with the U-shaped gradually expanding blunt body 4, it forms the main structure of the vortex control stabilizer as a whole. According to the different sizes of the vortex control stabilizer, the distance between the inner wall surface 5 and the outer wall surface 6 is 20 to 70 mm.

[0027] The U-shaped gradually expanding blunt body 4 is a closed cavity formed by an arc-shaped front wall 401, a gradually expanding side wall 402 and a rear end wall 403. The arc-shaped front wall 401 is the front end of the U-shaped gradually expanding blunt body 4, the rear end wall 403 is the rear end of the U-shaped gradually expanding blunt body 4, and the gradually expanding side wall 402 is connected between the arc-shaped front wall 401 and the rear end wall 403. The outer edge of the rear end wall 403 is connected to the outer wall surface 6, the inner wall surface 5 is located at the inner side edge of the rear end wall 403, and the annular radius of the inner wall surface 5 is smaller than the radius of the inner side edge of the rear end wall 403, so that an air intake slit 7 is formed between the inner wall surface 5 and the inner side edge of the rear end wall 403, and the air intake slit 7 is connected to the cavity between the inner wall surface 5 and the outer wall surface 6. As a preferred embodiment, the front side edge of the inner wall surface 5 and the inner side edge of the rear end wall 403 are flush in the axial direction of the stabilizer, so that the air intake slit 7 directly faces the incoming flow. According to the size of the vortex control stabilizer, the width w of the air inlet slot 7, that is, the distance between the front edge of the inner wall surface 5 and the inner edge of the rear end wall 403, is 2 to 8 mm. The angle of the gradually diverging side wall 402 is 25 to 40°, and 30° is most conducive to the balance of combustion stability, combustion efficiency and flow loss.

[0028] A guide plate 8 extending toward the outer wall 6 is also provided on the side of the inner wall 5 facing the outer wall 6. Depending on the size of the vortex-controlled stabilizer, the extension length of the guide plate 8, i.e., the height of the guide plate 8, is 5 to 30 mm. The guide plate 8 is arranged in parallel with the rear end wall 403 of the U-shaped gradually expanding blunt body 4, and an air intake gap 9 is formed between the two. The air intake gap 9 is connected to the air intake gap 7. After the incoming flow enters the air intake gap 7, it turns and enters the air intake gap 9 for radial flow, and then enters the cavity between the inner wall 5 and the outer wall 6. Depending on the size of the vortex-controlled stabilizer, the spacing d between the guide plate 8 and the rear end wall 403 of the U-shaped gradually expanding blunt body 4 is 2 to 8 mm.

[0029] The evaporator tube 3 is used to quickly evaporate the fuel and provide an oil-gas mixer to the cavity between the inner wall surface 5 and the outer wall surface 6. The evaporator tube 3 is connected to the rear end wall 403 and is arranged along the circumferential direction of the vortex-controlled stabilizer. The heat in the cavity between the inner wall surface 5 and the outer wall surface 6 is directly transferred to the evaporator tube 3 through the rear end wall 403 to promote the evaporation of the fuel. In order to strengthen the process in this embodiment, the evaporator tube 3 is embedded in the rear end wall 403, that is, the tube wall of the evaporator tube 3 is connected to the rear end wall 403 as a part of the rear end wall 403. The evaporator tube 3 is provided with a plurality of nozzles 301 leading to the area between the stabilizer walls, and the nozzles 301 are arranged toward the outer wall surface 6. Depending on the size of the vortex-controlled stabilizer, the diameter of the nozzle 301 is 1 to 5 mm.

[0030] The oil-gas mixture of the evaporation tube 3 is provided by the air inlet nozzle 1. The air inlet nozzle 1 is provided with a plurality of discretely arranged in the circumferential direction of the vortex control stabilizer. Figures 2 to 6 The vortex control stabilizer is represented as a unit structure with a section having an air inlet nozzle 1 on the ring. The air inlet nozzle 1 is arranged in the radial direction of the stabilizer, and extends from the arc front wall 401 into the closed cavity of the U-shaped gradually expanding blunt body 4 and communicates with the evaporation tube 3. The injection pipe 2 is connected to the pipe wall of the air inlet nozzle 1 in front of the arc front wall 401 of the U-shaped gradually expanding blunt body 4 to form an injection port 201 with a diameter of 1 to 5 mm, so that the injection pipe 2 is connected to the air inlet nozzle 1 from the side. The specific size of the injection port 201 is determined according to the size of the vortex control stabilizer. An oil spray plate 101 is provided at the outlet of the injection pipe 2 (i.e., the injection port 201) in the air inlet nozzle 1. A gap is left between the oil spray plate 10 and the outlet of the injection pipe 2. The oil spray plate 10 can further break up the large oil droplets entering from the injection pipe 2 under the collision effect, thereby improving the atomization effect of mixing with the incoming flow.

[0031] Please combine Figure 7 As shown, the working process of the vortex control stabilizer of the present invention is as follows:

[0032] When the mainstream two-phase mixed gas 11 flows out of the nozzle 301 of the evaporator tube 3 at a certain speed under the coupling effect of the air intake nozzle 1 and the fuel injection pipe 2, the gas in the cavity between the inner wall surface 5 and the outer wall surface 6 is forced to be sucked to form a local low-pressure area under the action of the viscous force. The tail speed of the mainstream mixed gas near this area will decrease, and the static pressure will increase, forming a pressure difference with the local low-pressure area in front. Under the action of the pressure difference, a part of the mainstream mixed gas flows to the rear end wall 403 of the stabilizer in the opposite direction of the mainstream speed. The whole process is continuous, and a single large-scale single vortex 12 recirculation area will be formed in the entire space.

[0033] Part of the mainstream air 13 enters the cavity between the inner wall surface 5 and the outer wall surface 6 through the air inlet slit 7 and the air inlet gap 9, generates radial velocity under the drainage action of the guide plate 8, and the air 13 entering the vortex control stabilizer is sucked into the low-pressure area after passing through the guide plate 8. Under the combined action of the guide plate 8 and the rear end face 403 of the vortex control stabilizer, the inner wall surface 5 and the outer wall surface 6, a large-scale stable single vortex 12 is formed in the cavity between the inner wall surface 5 and the outer wall surface 6, and a small-scale secondary vortex 14 is formed at the rear of the vortex control flame stabilizer to protect the large-scale stable single vortex 12.

[0034] In addition, the fuel 15 is enhanced in atomization, evaporation and mixing effect under the action of the fuel spray splash plate 10 and the evaporation tube 3, thereby improving the oil-gas mixing degree and strengthening the combustion process.

[0035] By strengthening the combustion process and forming a large-scale single vortex 12 flow structure, it is insensitive to changes in airflow velocity due to the protection of the small-scale auxiliary vortex 14 formed on the various surfaces of the stabilizer and behind the stabilizer. It can remain stable within a wider range of operating conditions, thereby achieving ignition and flame stability at higher incoming flow velocities, improving ignition and flameout performance, strengthening the exchange of momentum and heat of the stabilizer, reducing combustion oscillations, and improving combustion efficiency.

Claims

1. A vortex-controlled stabilizer, wherein the vortex-controlled stabilizer is characterized in that: The invention comprises an air intake nozzle, an oil injection pipe, an evaporation pipe, a U-shaped gradually expanding blunt body and a stabilizer wall, wherein the U-shaped gradually expanding blunt body is formed with a closed cavity by an arc-shaped front wall, a gradually expanding side wall and a rear end wall, the evaporation pipe is connected to the rear end wall, the evaporation pipe is provided with a plurality of nozzles leading to the area between the stabilizer walls, the air intake nozzle is provided with a plurality of nozzles and is discretely arranged along the circumferential direction of the vortex control stabilizer, the air intake nozzle extends from the arc-shaped front wall into the closed cavity of the U-shaped gradually expanding blunt body and is connected to the evaporation pipe, the oil injection pipe is connected to the evaporation pipe from the side of the air intake nozzle The air intake nozzle is connected, and an oil splash plate is provided in the air intake nozzle at the outlet position of the oil injection pipe, and a gap is left between the oil splash plate and the outlet of the oil injection pipe; the stabilizer wall surface includes an inner wall surface and an outer wall surface, and the inner wall surface and the outer wall surface are respectively located at the inner and outer edges of the rear end wall of the U-shaped gradually expanding blunt body, and an air intake gap is left between the inner wall surface and the inner edge of the rear end wall, and the inner wall surface is provided with a guide plate extending toward the outer wall surface, and an air intake gap is formed between the guide plate and the rear end wall, and the air intake gap is connected to the air intake gap.

2. The vortex-controlled stabilizer according to claim 1, characterized in that: The evaporation tube is embedded in the rear end wall, and the nozzle is arranged toward the outer wall surface.

3. The vortex controlled stabilizer according to claim 1 or 2, characterized in that: The diameter of the fuel injection port formed by the fuel injection pipe being connected to the air intake nozzle is 1 to 5 mm.

4. The vortex controlled stabilizer according to claim 1 or 2, characterized in that: The nozzle diameter of the evaporation tube is 1 to 5 mm.

5. The vortex controlled stabilizer according to claim 1 or 2, characterized in that: The included angle of the gradually expanding side wall of the U-shaped gradually expanding blunt body is 20-40°.

6. The vortex controlled stabilizer according to claim 1 or 2, characterized in that: The distance between the inner wall surface and the outer wall surface of the vortex control stabilizer is 20 to 70 mm.

7. The vortex-controlled stabilizer according to claim 6, characterized in that: The distance between the inner wall surface and the inner edge of the rear end wall is 2 to 8 mm.

8. The vortex-controlled stabilizer according to claim 7, characterized in that: The distance between the guide plate and the rear end wall is 2 to 8 mm.

9. The vortex controlled stabilizer according to claim 6, characterized in that: The height of the guide plate is 5 to 30 mm.

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