An air-cooled vortex control stabilizer

Abstract

The invention discloses an air-cooled vortex control stabilizer, comprising an oil supply pipe, an evaporator pipe, a U-shaped gradually expanding blunt body and a stabilizer wall surface, wherein the oil supply pipe and the evaporator pipe are arranged in the U-shaped gradually expanding blunt body, the evaporator pipe is connected to the rear end wall and is provided with a mixed gas outlet hole, the air inlet nozzle is located on the arc front wall and is discretely arranged along the annular direction of the air-cooled vortex control stabilizer, the air inlet nozzle is connected to the evaporator pipe through an air inlet duct, the side wall of the air inlet duct is provided with an oil inlet connected to the oil supply pipe, the stabilizer wall surface is arranged on both sides of the rear end wall and includes a first wall surface and a second wall surface, each side wall surface is an annular groove structure composed of an inner wall surface and an outer wall surface, the opening is located on both sides of the rear end wall and is directly facing the incoming flow, a plurality of cooling holes are provided on the inner wall surface, a first air inlet hole with a larger aperture than the cooling hole is provided on the inner wall surface of the first wall surface close to the rear end surface, and the mixed gas outlet hole of the evaporator pipe faces the second wall surface. The invention can maintain flame stability and device durability when a high temperature rise phenomenon occurs in an afterburner.

Description

Technical Field

[0001] The invention relates to an air-cooled vortex control stabilizer, belonging to the technical field of flame stabilization devices in aircraft combustion chambers. Background Art

[0002] With the continuous improvement of thrust-to-weight ratio requirements for advanced military aviation engines, afterburners are developing towards higher temperature rise. However, they are facing huge technical challenges during their development: the total oil-gas ratio and heat release rate of high temperature rise afterburners are very high, and due to the heat resistance of the device materials, a lower temperature distribution coefficient of the afterburner is required; the heat capacity of high temperature rise afterburners is relatively large, which brings technical challenges in terms of visible smoke and wall cooling; at the same time, high temperature rise afterburners are prone to fuel-poor flameout or unstable combustion, and the flameout oil-gas ratio is much higher than the general flameout oil-gas ratio of the combustion chamber. How to take into account the harsh working environment of high temperature and high pressure and ensure a certain degree of reliability and durability is the basic challenge faced by afterburners.

[0003] Based on the above characteristics of high temperature rise in the afterburner, how to achieve flame-stabilized combustion and the durability of the device has become a key issue. The vortex-controlled stabilizer disclosed in Publication No. CN118328419A still has the following problems: 1) The oil pipeline is mainly arranged on the outside of the stabilizer, resulting in a large total pressure loss in the afterburner, and is easily subject to thermal stress in the high-temperature rise afterburner, and the oil pipeline is easily damaged. 2) The oil pipeline is installed on the outside, and the internal fuel directly faces the high-temperature airflow discharged by the turbine, which is easy to cause coke inside the pipeline and block the fuel transportation. 3) Due to the overheating of the wall temperature of the vortex-controlled stabilizer during the operation of the afterburner, the stabilizer wall warps and cracks and other faults. 4) In the single-side wall-guided intake mode of the vortex-controlled stabilizer, the fuel stays in the stabilizer for a short time, which is easy to cause partial waste of fuel. Summary of the invention

[0004] In view of the above-mentioned defects of the prior art, the task of the present invention is to provide an air-cooled vortex control stabilizer to solve the problems of stabilizer reliability and durability in the harsh working environment of high temperature and high pressure of afterburner.

[0005] The technical solution of the present invention is as follows: an air-cooled vortex control stabilizer comprises an air inlet nozzle, an oil supply pipe, an evaporator pipe, a U-shaped gradually expanding blunt body and a stabilizer wall surface, wherein the U-shaped gradually expanding blunt body is formed into a closed cavity by an arc-shaped front wall, a gradually expanding side wall and a rear end wall, wherein the oil supply pipe and the evaporator pipe are arranged in the U-shaped gradually expanding blunt body, wherein the evaporator pipe is connected to the rear end wall, wherein the evaporator pipe is provided with a plurality of mixed gas outlet holes leading to the area between the stabilizer wall surfaces, wherein the air inlet nozzle is located on the arc-shaped front wall and is discretely arranged in a plurality of circumferential directions of the air-cooled vortex control stabilizer, wherein the air inlet nozzle is connected to the evaporator pipe through an air inlet duct, wherein the An oil inlet is provided on the side wall of the intake duct, and the oil supply pipe is connected to the intake duct through the oil inlet. The stabilizer wall surface is arranged on both sides of the rear end wall and includes a first wall surface and a second wall surface. The stabilizer wall surface is an annular groove structure composed of an inner wall surface and an outer wall surface. The opening of the stabilizer wall surface is located on both sides of the rear end wall and faces the incoming flow. A plurality of cooling holes are provided on the inner wall surface. A first air inlet hole with an aperture larger than that of the cooling hole is provided on a side of the inner wall surface of the first wall surface close to the rear end wall, and the mixed gas outlet hole of the evaporator tube faces the second wall surface.

[0006] The present invention combines the advantages of oil-gas mixing and flame stabilization of the vortex-controlled stabilizer, arranges the oil supply pipe inside the U-shaped gradually expanding blunt body, protects the oil supply pipe from overheating in the high temperature rise environment of the afterburner, and continuously provides mixed oil and gas for the stabilizer; at the same time, the outer wall and the inner wall adopt a sandwich design and an inner wall cooling hole design to prevent the wall from being overheated and causing damage to the device; the first air inlet hole arranged on the first wall cooperates with the mixed gas outlet hole on the second wall to form a stable larger-scale vortex, thereby achieving stable combustion of the flame and improving the durability of the device.

[0007] Furthermore, a second air inlet hole having a larger aperture than that of the cooling hole is provided on the inner wall of the second wall away from the rear end wall. Air inlet holes are provided on both the first wall and the second wall, forming front and rear air inlets between the stabilizer walls, which can extend the residence time of the fuel inside the stabilizer and improve the combustion efficiency.

[0008] Furthermore, a first baffle is provided between the inner wall and the outer wall of the first wall, the first baffle is provided with a plurality of first air holes arranged toward the opening of the stabilizer wall, the first baffle is located between the first air inlet hole and the cooling hole of the inner wall of the first wall, a second baffle is provided between the inner wall and the outer wall of the second wall, the second baffle is provided with a plurality of second air holes arranged toward the opening of the stabilizer wall, and the second baffle is located before the cooling holes of the inner wall of the second wall. By providing the first baffle with the first air holes and the second baffle with the second air holes, it is ensured that the incoming air forms a pressure difference, and that the cooling holes of the inner wall and the inside of the stabilizer continuously and stably inlet air.

[0009] Furthermore, in order to improve the atomization effect of the fuel, improve the oil-gas mixing effect before entering the evaporator tube, and accelerate the degree of fuel fragmentation, a splash baffle is provided at the fuel inlet in the intake duct, and a gap is left between the splash baffle and the fuel inlet.

[0010] Furthermore, the evaporation tube is embedded in the rear end wall.

[0011] Furthermore, the diameter of the mixed gas outlet hole of the evaporation tube is 1 to 3 mm.

[0012] Furthermore, the included angle of the gradually diverging side wall of the U-shaped gradually diverging blunt body is 10° to 40°.

[0013] Furthermore, the distance between the inner wall surface and the outer wall surface of the stabilizer wall on one side is 2 to 5 mm.

[0014] Furthermore, the apertures of the first air inlet hole and the second air inlet hole are 3-7 mm, and the aperture of the cooling hole is 0.5-2 mm.

[0015] Furthermore, the diameters of the first pores and the second pores are 2 to 5 mm.

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

[0017] The double-layer wall is combined with the cooling hole. The cooling hole gives full play to the heat exchange process of the divergent hole wall, improves the utilization rate of the cooling air in the outer duct, reduces the consumption of cooling air, and reduces the device breakage or distortion caused by thermal stress of the stabilizer. The embedded layout of the fuel supply pipe reduces the carbonization and premature combustion of the fuel supply pipe caused by overheating of the afterburner, ensuring the durability of the stabilizer device. The internal double-sided air intake conforms to the flow law of the larger-scale vortex formed, enhances the stability of the vortex, and increases the residence time of the fuel. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the three-dimensional structure of the air-cooled vortex control 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 air-cooled vortex control stabilizer of the present invention.

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

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

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

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

[0024] Figure 7 for Figure 5 Schematic diagram of BB section.

[0025] Figure 8 This is a working principle diagram of the invented air-cooled vortex control stabilizer. DETAILED DESCRIPTION

[0026] The present invention will be further described below in conjunction with the embodiments, but are not intended to limit the present invention.

[0027] Please combine Figure 1 and Figure 2 As shown, the air-cooled vortex control stabilizer involved in the embodiment of the present invention is an annular extended structure as a whole, which includes an air inlet nozzle 1, an oil supply pipe 2, an evaporator pipe 3, a U-shaped gradually expanding blunt body 4 and a stabilizer wall.

[0028] 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 a connecting wall surface connected between the arc-shaped front wall 401 and the rear end wall 403. The angle of the gradually expanding side wall 402 is 10 to 40 degrees, and when it is 30 degrees, it is most conducive to the balance of combustion stability, combustion efficiency and flow loss.

[0029] The stabilizer wall has two surfaces, namely the first wall and the second wall, which are arranged on both sides of the rear end wall 403 of the U-shaped gradually expanding bluff body 4 and connected to the rear end wall 403. The first wall and the second wall and the U-shaped gradually expanding bluff body 4 together form the main structure of the air-cooled vortex control stabilizer.

[0030] The first wall and the second wall are both annular groove structures and are arranged parallel to the incoming air flow (i.e., arranged along the axial direction of the air-cooled vortex control stabilizer). The first wall is composed of an inner wall 5 and an outer wall 6, and the second wall is composed of an inner wall 501 and an outer wall 601, wherein the inner wall 5 of the first wall and the inner wall 501 of the second wall are the walls located in the inner ring of the annular structure of the air-cooled vortex control stabilizer body, and the outer wall 6 of the first wall and the outer wall 601 of the second wall are the walls located in the outer ring of the annular structure. The first wall and the second wall form openings 9, 901 facing the incoming air flow on both sides of the rear end wall 403, that is, there is a gap between the inner wall 5 and the outer wall 6 of the first wall and between the inner wall 501 and the outer wall 601 of the second wall, so that air enters the first wall and the second wall. According to the different sizes of the air-cooled vortex control stabilizer, the spacing between the inner wall surface 5 and the outer wall surface 6 of the first wall surface and between the inner wall surface 501 and the outer wall surface 601 of the second wall surface are both 2 to 5 mm, and the spacing between the inner wall surface 5 of the first wall surface and the inner wall surface 501 of the second wall surface is 20 to 80 mm.

[0031] A plurality of first air inlet holes 8 and cooling holes 10 are opened on the inner wall surface 5 of the first wall surface, and the first air inlet hole 8 is on the side of the inner wall surface 5 close to the rear end wall 403 of the U-shaped gradually expanding blunt body 4. A plurality of cooling holes 101 and second air inlet holes 801 are opened on the inner wall surface 501 of the second wall surface, and the second air inlet hole 801 is on the side of the inner wall surface 501 away from the rear end wall 403 of the U-shaped gradually expanding blunt body 4. The apertures of the cooling holes 10, 101 are 0.5-2 mm, and the apertures of the first air inlet holes 8 and the second air inlet holes 801 are 3-7 mm. As a preferred embodiment, baffles are provided between the inner wall surface 5 and the outer wall surface 6 of the first wall surface and between the inner wall surface 501 and the outer wall surface 601 of the second wall surface, wherein the baffle of the first wall surface is located between the first air inlet hole 8 and the cooling hole 10 of the inner wall surface 5, and the baffle of the second wall surface is located before the cooling hole 101 of the inner wall surface 501. The baffle plate of the first wall is provided with a first air hole 7 parallel to the incoming flow direction, and the first air hole 7 is perpendicular to the first air inlet 8. The baffle plate of the second wall is provided with a second air hole 701 parallel to the incoming flow direction, and the second air hole 701 is perpendicular to the second air inlet 801. The apertures of the first air hole 7 and the second air hole 701 are 2 to 5 mm. The air inlet holes 7 and 701 are in a vertical layout relationship with the guide holes 8 and 801, and the two are arranged in a staggered distributed manner.

[0032] The evaporation tube 3 is used to quickly evaporate the fuel and provide an oil-gas mixer to the cavity between the inner wall surface 5 of the first wall and the inner wall surface 501 of the second wall. The evaporation tube 3 is connected to the rear end wall 403 and is arranged along the circumferential direction of the air-cooled vortex control stabilizer. The heat in the cavity between the inner wall surface 5 of the first wall and the inner wall surface 501 of the second wall is directly conducted to the evaporation tube 3 through the rear end wall 403 to promote the evaporation of the fuel. In this embodiment, in order to strengthen the process, the evaporation tube 3 is embedded in the rear end wall 403, that is, the tube wall of the evaporation tube 3 is connected to the rear end wall 403 as a part of the rear end wall 403. The evaporation tube 3 is provided with a plurality of mixed gas outlet holes 301 leading to the area between the stabilizer walls, and the mixed gas outlet holes 301 are arranged toward the inner wall surface 501 of the second wall. According to the size of the air-cooled vortex control stabilizer, the aperture of the mixed gas outlet hole 301 is 1 to 3 mm.

[0033] The oil-gas mixture of the evaporator tube 3 is provided by the air intake nozzle 1 and the oil supply pipe 2. The air intake nozzle 1 is provided with a plurality of air intake nozzles and is discretely arranged along the annular direction of the air-cooled vortex control stabilizer. The air intake nozzle 1 is connected to the evaporator tube 3 through a corresponding number of air intake ducts arranged along the axial direction of the air-cooled vortex control stabilizer. In addition, the oil supply pipe 2 is connected in a circular ring shape, and the oil supply pipe 2 is connected to the air intake duct through a sub-oil supply pipe 201 corresponding to the number of air intake nozzles 1 to form an oil inlet on the air intake duct. The specific size of the oil inlet is determined according to the size of the air-cooled vortex control stabilizer. A splash baffle 11 is provided at a certain distance from the oil inlet in the air intake duct. The splash baffle 11 can further break up the large oil droplets entering from the sub-oil supply pipe 201 under the action of collision, thereby improving the atomization effect of mixing with the incoming flow.

[0034] Please combine Figure 8 As shown, the working process of the air-cooled vortex control stabilizer of the present invention is as follows:

[0035] When the mainstream air 14 passing through the air inlet nozzle 1 and the fuel 15 passing through the fuel supply pipe 2 and the sub-fuel supply pipe 201 form a two-phase mixed gas 12 and flow out from the mixed gas outlet 301 of the evaporator tube 3 at a certain speed, under the action of the viscous force, the gas in the cavity between the inner wall surface 5 of the first wall surface and the inner wall surface 501 of the second wall surface is forced to be sucked to form a local low-pressure area. The tail speed of the two-phase 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 two-phase 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 13 recirculation area will be formed in the entire space.

[0036] Part of the mainstream air 14 enters between the first wall and the second wall through the opening 9 of the first wall and the opening 901 of the second wall. The staggered arrangement of the first air inlet 8, the second air inlet 801 and the first air hole 7, the second air hole 701 allows part of the air to enter the cavity between the inner wall surface 5 of the first wall and the inner wall surface 501 of the second wall along the first air inlet 8, the second air inlet 801, and generates opposite radial velocities under the drainage action of the first air inlet 8, the second air inlet 801. The air 14 entering the air-cooled vortex control stabilizer is sucked into the low-pressure area after passing through the first air inlet 8, the second air inlet 801. Under the combined action of the first air inlet 8, the second air inlet 801 and the rear end wall 403 of the air-cooled vortex control stabilizer, the inner wall surface 5 of the first wall and the inner wall surface 501 of the second wall, a large-scale stable single vortex 13 is formed in the cavity between the inner wall surface 5 of the first wall and the inner wall surface 501 of the second wall. At the same time, another part of the air radially enters the cavity between the inner wall surface 5 of the first wall and the inner wall surface 501 of the second wall through the cooling holes 10 of the first wall and the cooling holes 101 of the second wall. This part of the cooling air can reduce the temperature of the stabilizer wall, ensure that the wall temperature gradient of the stabilizer is within the acceptable range of thermal stress, and improve the service life of the stabilizer.

[0037] The air-cooled vortex control stabilizer adopts trapped vortex combustion organization technology and utilizes the aerodynamics and turbulent combustion principles of the afterburner to organically coordinate the flow of air 14 and the distribution of fuel 15 in the cavity between the inner wall surface 5 of the first wall and the inner wall surface 501 of the second wall, organizing them into optimal oil and gas distribution and robust reflow zone 13, achieving controllable, stable and continuous combustion while ensuring the temperature resistance and durability of the stabilizer, achieving stable combustion in the afterburner while meeting the challenges of high temperature rise afterburner.

Claims

1. An air-cooled vortex control stabilizer, comprising an air inlet nozzle, an oil supply pipe, an evaporator pipe, a U-shaped gradually expanding blunt body and a stabilizer wall, wherein the U-shaped gradually expanding blunt body is formed into a closed cavity by an arc-shaped front wall, a gradually expanding side wall and a rear end wall, characterized in that: The oil supply pipe and the evaporator pipe are arranged in the U-shaped gradually expanding blunt body, the evaporator pipe is connected to the rear end wall, the evaporator pipe is provided with a plurality of mixed gas outlet holes leading to the area between the stabilizer wall surfaces, the air inlet nozzle is located on the arc-shaped front wall and is discretely arranged in a plurality of directions along the circumferential direction of the air-cooled vortex control stabilizer, the air inlet nozzle is connected with the evaporator pipe through the air inlet duct, the side wall of the air inlet duct is provided with an oil inlet, the oil supply pipe is connected with the air inlet duct through the oil inlet, the stabilizer wall surface is arranged on both sides of the rear end wall and includes a first wall surface and a second wall surface, the stabilizer wall surface is an annular groove structure composed of an inner wall surface and an outer wall surface, the openings of the stabilizer wall surface are located on both sides of the rear end wall and face the incoming flow, a plurality of cooling holes are provided on the inner wall surface, and the inner wall surface of the first wall surface is close to the A first air inlet hole with a larger aperture than that of the cooling hole is formed on one side of the rear end wall, and a mixed gas outlet hole of the evaporator tube faces the second wall surface, and a second air inlet hole with a larger aperture than that of the cooling hole is formed on the inner wall surface of the second wall surface away from the rear end wall; a first baffle is provided between the inner wall surface and the outer wall surface of the first wall surface, and a plurality of first air holes are provided on the first baffle surface and are opened toward the stabilizer wall surface, and the first baffle is located between the first air inlet hole and the cooling hole on the inner wall surface of the first wall surface, and a second baffle is provided between the inner wall surface and the outer wall surface of the second wall surface, and a plurality of second air holes are provided on the second baffle surface and are opened toward the stabilizer wall surface, and the second baffle is located before the cooling holes on the inner wall surface of the second wall surface.

2. The air-cooled vortex control stabilizer according to claim 1, characterized in that: A splash baffle is provided at the oil inlet in the air inlet passage, and a gap is left between the splash baffle and the oil inlet.

3. The air-cooled vortex control stabilizer according to claim 1, characterized in that: The evaporation tube is embedded in the rear end wall.

4. The air-cooled vortex control stabilizer according to claim 1, characterized in that: The diameter of the mixed gas outlet hole of the evaporation tube is 1 to 3 mm.

5. The air-cooled vortex control stabilizer according to claim 1, characterized in that: The included angle of the gradually expanding side wall of the U-shaped gradually expanding blunt body is 10-40°.

6. The air-cooled vortex control stabilizer according to claim 1, characterized in that: The distance between the inner wall surface and the outer wall surface of the stabilizer wall on one side is 2 to 5 mm.

7. The air-cooled vortex control stabilizer according to claim 1, characterized in that: The apertures of the first air inlet hole and the second air inlet hole are 3-7 mm, and the aperture of the cooling hole is 0.5-2 mm.

8. The air-cooled vortex control stabilizer according to claim 1, characterized in that: The diameters of the first pores and the second pores are 2 to 5 mm.

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