A flame tube with swirling air intake

Abstract

The present invention relates to a flame tube with swirling air intake, which comprises a flame tube head cavity, an inner ring of the flame tube and an outer ring of the flame tube. The flame tube head cavity is connected to the inner ring of the flame tube and the outer ring of the flame tube, and the inner ring of the flame tube is located in the inner cavity of the outer ring of the flame tube. A main air intake hole and a forward air intake guiding groove are arranged at the front end of the flame tube head cavity, and a rear air intake guiding groove is arranged at the rear end of the flame tube head cavity. Inner wall mixing holes are arranged on the inner ring of the flame tube, and outer wall mixing holes are arranged on the outer ring of the flame tube. The present invention improves the fuel atomization quality, strengthens the fuel-air mixing, enables the combustion to be more sufficient, and improves the combustion efficiency.

Description

Technical Field

[0001] The present invention relates to a flame tube with swirling air intake, which can be used in a plateau trapped-vortex combustor and belongs to the field of aviation technology. Background Art

[0002] The combustor is the core component of a micro turbojet engine, which converts the chemical energy of fuel into heat energy to provide energy for the engine. Its performance directly determines the performance of the engine. There are two major problems with the combustor under the "low pressure and low oxygen" conditions on the plateau: First, efficient combustion; Second, reliable ignition. How to improve the ignition reliability, stability, and combustion efficiency as much as possible in a limited space, and at the same time, minimize the size of the combustor while ensuring performance is an urgent problem to be solved in the development of plateau-type turbojet engines. Therefore, it is necessary to theoretically master the performance characteristics and laws of plateau combustors, develop advanced combustion technologies in engineering, and propose a new type of combustor - the plateau trapped-vortex combustor.

[0003] The trapped-vortex combustor adopts a staged fuel supply and zoned combustion organization method, uses a cavity to generate a recirculation zone to stabilize the flame, has strong adaptability to the inlet aerodynamic parameters of the combustor, and has the advantages of compact structure, strong flame stability, wide operating range, easy ignition, low lean blowout limit, and high combustion efficiency. The structure of the flame tube is extremely important. Therefore, the research on the trapped-vortex combustor flame tube needs to be improved, which will be of great help to the improvement of the combustor performance. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the present invention aims to provide a flame tube with swirling air intake, which can improve the fuel atomization quality, strengthen the fuel-air mixing, make the combustion more complete, and improve the combustion efficiency.

[0005] The present invention is realized through the following technical solutions.

[0006] A flame tube with swirling air intake includes a concave cavity at the head of the flame tube, an inner ring of the flame tube, and an outer ring of the flame tube. The concave cavity at the head of the flame tube is connected to the inner ring and the outer ring of the flame tube, and the inner ring of the flame tube is located in the inner cavity of the outer ring of the flame tube;

[0007] At the front end of the concave cavity at the head of the flame tube, there are main air intake holes and forward air intake diversion grooves. At the rear end of the concave cavity at the head of the flame tube, there is a rear air intake diversion groove. The opening diameter of the main air intake holes is 6 - 8 mm, and 16 main air intake holes are evenly distributed. The width and height of the forward air intake diversion grooves are both 2 mm, and the length is 4 - 6 mm. The forward air intake diversion grooves are inclined holes rotating clockwise and are arranged circumferentially for 90. The width and height of the rear air intake diversion grooves are both 2 mm, and the length is 4 - 6 mm. The rear air intake diversion grooves are inclined holes rotating counterclockwise and are arranged circumferentially for 60;

[0008] The inner ring of the combustion chamber is provided with inner wall mixing holes. The opening diameter of the inner wall mixing holes is 6 - 8 mm, and there are 8 inner wall mixing holes arranged staggeredly.

[0009] The outer ring of the combustion chamber is provided with outer wall mixing holes. The opening diameter of the outer wall mixing holes is 6 - 8 mm, and there are 16 outer wall mixing holes arranged staggeredly.

[0010] Furthermore, the total length of the entire combustion chamber is 165 mm, the outer radius of the concave cavity at the head of the combustion chamber is 118 mm, the inner radius of the inner ring of the combustion chamber is 40 mm, and the thickness is 0.5 mm; the length of the concave cavity at the head of the combustion chamber is 50 mm, and the height is 35 mm; the outlet height of the combustion chamber is 36 mm, and the outer radius of the combustion chamber wall is 400 mm.

[0011] Compared with the prior art, the advantages and beneficial effects of the present invention are as follows:

[0012] First, the flame is more stable. The swirling intake air in the concave cavity at the head of the combustion chamber makes the recirculation zone in the concave cavity at the head of the combustion chamber more stable. The vortex structure in the concave cavity at the head of the combustion chamber is not affected by the mainstream, and the flame in the concave cavity at the head of the combustion chamber is more stable.

[0013] Second, the combustion efficiency is improved. The swirling intake air in the concave cavity at the head of the combustion chamber increases the circumferential flow distance of the air flow and the fuel residence time, enabling the fuel to burn fully in the concave cavity at the head of the combustion chamber and improving the combustion efficiency.

[0014] Third, the circumferential flame linking performance is improved. The aerodynamic force is used to accelerate the circumferential transmission speed of the flame, strengthen the mass and energy transfer between the heads, and improve the circumferential flame linking performance of the engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 An isometric view of the combustion chamber involved in the present invention.

[0016] Figure 2 A partial cross-sectional view of the combustion chamber involved in the present invention.

[0017] Figure 3 A side view of the combustion chamber involved in the present invention.

[0018] Figure 4 is Figure 3 an enlarged view of part A in

[0019] Figure 5 A partial cross-sectional view of the forward air guide groove involved in the present invention.

[0020] Figure 6 A cross-sectional flow field diagram of the combustion chamber involved in the present invention.

[0021] Figure 7It is the streamline diagram of the combustion chamber involved in the present invention.

[0022] In the figure: 1. Combustion chamber head cavity, 101. Mainstream intake hole, 102. Forward intake guide groove, 103. Rear intake guide groove;

[0023] 2. Inner ring of the combustion chamber, 201. Inner wall mixing hole;

[0024] 3. Outer ring of the combustion chamber, 301. Outer wall mixing hole. Specific embodiments

[0025] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but it is not limited to the present invention.

[0026] As Figures 1 to 7 shown, a combustion chamber with swirl intake includes a combustion chamber head cavity 1, an inner ring 2 of the combustion chamber, and an outer ring 3 of the combustion chamber. The combustion chamber head cavity 1 is connected to the inner ring 2 and the outer ring 3 of the combustion chamber. The inner ring of the combustion chamber is located in the inner cavity of the outer ring of the combustion chamber;

[0027] At the front end of the combustion chamber head cavity 1, there are a mainstream intake hole 101 and a forward intake guide groove 102. At the rear end of the combustion chamber head cavity 1, there is a rear intake guide groove 103; the opening diameter of the mainstream intake hole 101 is 6 - 8 mm, and 16 mainstream intake holes 101 are evenly distributed; the width and height of the forward intake guide groove 102 are both 2 mm, and the length is 4 - 6 mm. The forward intake guide groove 102 is an inclined hole rotating clockwise, and 90 are arranged circumferentially; the width and height of the rear intake guide groove 103 are both 2 mm, and the length is 4 - 6 mm. The rear intake guide groove 103 is an inclined hole rotating counterclockwise, and 60 are arranged circumferentially;

[0028] On the inner ring 2 of the combustion chamber, there is an inner wall mixing hole 201. The opening diameter of the inner wall mixing hole 201 is 6 - 8 mm, and there are 8 inner wall mixing holes 201, which are arranged staggeredly;

[0029] On the outer ring 3 of the combustion chamber, there is an outer wall mixing hole 301. The opening diameter of the outer wall mixing hole 301 is 6 - 8 mm, and there are 16 outer wall mixing holes 301, which are arranged staggeredly.

[0030] Furthermore, the total length of the entire combustion chamber is 165 mm, the outer radius of the combustion chamber head cavity 1 is 118 mm, the inner radius of the inner ring 2 of the combustion chamber is 40 mm, and the thickness is 0.5 mm; the length of the combustion chamber head cavity 1 is 50 mm, and the height is 35 mm; the outlet height of the combustion chamber is 36 mm, and the outer radius of the combustion chamber wall is 400 mm.

[0031] Working principle: After the high-pressure air flowing out of the centrifugal compressor diffuser enters the combustion chamber, it is mainly divided into two streams; most of the first stream of air flows into the cavity 1 at the head of the flame tube through the front air inlet guide groove 102 and the rear air inlet guide groove 103, forming a recirculation zone in the cavity 1 at the head of the flame tube to stabilize the flame. The cavity 1 at the head of the flame tube undertakes the ignition of the combustion chamber and combustion under all working conditions, and most of the fuel burns here; most of the second stream of air flows in from the main air inlet hole 101 and interacts with the air in the cavity 1 at the head of the flame tube to form an intermediate zone, participating in afterburning, which can further promote combustion and improve the combustion efficiency; a small part of the first and second streams of gas enter the flame tube through the outer wall mixing holes 301 and the inner wall mixing holes 201 to form a mixing zone for regulating the temperature at the outlet of the combustion chamber.

[0032] This kind of flame tube with swirl air intake adopts axial-zone combustion, increases the intermediate zone, can improve the combustion efficiency, reduce the combustion emission pollution, and has a relatively simple structure.

[0033] The above are only the preferred embodiments of the present invention, and do not limit the implementation manners and protection scope of the present invention. For those skilled in the art, it should be realized that all the equivalent replacements and obvious changes made by using the description and illustrations of the present invention should be included in the protection scope of the present invention.

Claims

1. A flame tube with swirl intake air, characterized in that, It includes a flame tube head cavity (1), an inner ring of the flame tube (2), and an outer ring of the flame tube (3). The flame tube head cavity (1) is connected to the inner ring of the flame tube (2) and the outer ring of the flame tube (3), and the inner ring of the flame tube is located in the inner cavity of the outer ring of the flame tube; At the front end of the flame tube head cavity (1), there are a main air inlet hole (101) and a forward air inlet guide groove (102). At the rear end of the flame tube head cavity (1), there is a rear air inlet guide groove (103). The opening diameter of the main air inlet hole (101) is 6 - 8 mm, and 16 main air inlet holes (101) are evenly distributed. The width and height of the forward air inlet guide groove (102) are both 2 mm, and the length is 4 - 6 mm. The forward air inlet guide groove (102) is an inclined hole rotating clockwise, and 90 are arranged circumferentially. The width and height of the rear air inlet guide groove (103) are both 2 mm, and the length is 4 - 6 mm. The rear air inlet guide groove (103) is an inclined hole rotating counterclockwise, and 60 are arranged circumferentially; On the inner ring of the flame tube (2), there are inner wall mixing holes (201). The opening diameter of the inner wall mixing holes (201) is 6 - 8 mm, and there are 8 inner wall mixing holes (201), which are arranged staggeredly; On the outer ring of the flame tube (3), there are outer wall mixing holes (301). The opening diameter of the outer wall mixing holes (301) is 6 - 8 mm, and there are 16 outer wall mixing holes (301), which are arranged staggeredly; The total length of the entire flame tube is 165 mm. The outer radius of the flame tube head cavity (1) is 118 mm. The inner radius of the inner ring of the flame tube (2) is 40 mm, and the thickness is 0.5 mm. The length of the flame tube head cavity (1) is 50 mm, and the height is 35 mm. The outlet height of the flame tube is 36 mm, and the outer radius of the flame tube wall is 400 mm.

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