A strut flame stabilizer with a U-shaped groove

Abstract

The present invention relates to a strut flame stabilizer with hoof-shaped grooves. The strut flame stabilizer consists of a leading edge, a straight section, and a V-shaped bottom surface. There are 3 to 5 hoof-shaped grooves arranged on both side surfaces of the straight section. The advantages and beneficial effects of the present invention are as follows: When the afterburner adopts the strut flame stabilizer with hoof-shaped grooves, it has good flame stabilization performance, high combustion efficiency, and small flow resistance loss.

Description

Technical Field

[0001] The invention relates to a support plate flame stabilizer with a horseshoe-shaped groove, which can be used for an integrated afterburner combustion chamber of an aero-engine with a high thrust-to-weight ratio, and belongs to the field of aeronautical technology. Background Art

[0002] The new generation of afterburning turbofan engines pursues a high thrust-to-weight ratio. In terms of the afterburner, it requires simple parts, low cold flow resistance loss, a small proportion of the afterburner section length, and high afterburner combustion efficiency. The afterburner uses a flame stabilizer to stabilize the flame and organize combustion. The performance of the flame stabilizer is a decisive factor affecting the performance of the afterburner. Most of the new generation of afterburner turbofan engines use an integrated afterburner with an integrated design of a rectifier support plate and a flame stabilizer. However, conventional support plate flame stabilizers produce Karman vortex street-type recirculation vortices, which have poor stability and can lead to locally unstable combustion.

[0003] Due to the small proportion of the afterburner section length, the distance from the fuel injection to the trailing edge of the flame stabilizer becomes smaller accordingly. The fuel atomization, evaporation and mixing are not sufficient before ignition, which can easily lead to unstable combustion. When combined with the unstable combustion caused by the recirculation vortex, the combustion instability problem will be amplified, thereby affecting the combustion reaction process. The distance from the trailing edge of the flame stabilizer to the nozzle outlet becomes smaller accordingly, the combustion section becomes shorter, and the flame in the recirculation zone behind the flame stabilizer does not have time to spread horizontally throughout the entire combustion chamber. Part of the oil-gas mixture is not fully burned, and part of the oil-gas mixture does not participate in combustion and is directly discharged, which seriously affects the afterburner combustion efficiency. Summary of the invention

[0004] The object of the present invention is to provide a support plate flame stabilizer with horseshoe-shaped grooves, wherein horseshoe-shaped grooves are arranged on both sides of the support plate flame stabilizer to improve flame stability, reduce flow loss and increase combustion efficiency.

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

[0006] The utility model relates to a support plate flame stabilizer with horseshoe-shaped grooves. 3 to 5 horseshoe-shaped grooves are evenly arranged on both sides of the support plate flame stabilizer.

[0007] Furthermore, the support plate flame stabilizer has a chord length of 90 to 150 mm, and the extension is determined by the specific engine. It consists of a leading edge, a straight section, and a V-shaped bottom surface. The leading edge is an elliptical surface, and the major axis of the ellipse is 1.7 to 2.5 times the minor axis. The leading edge is tangent to the straight section, the straight section is 24 to 36 mm wide, and the V-shaped bottom surface has an angle of 100° to 150°.

[0008] Furthermore, for the U-shaped groove, its trailing edge is flush with the trailing edge of the strut flame stabilizer. The length of the trailing edge of the U-shaped groove is 40 - 50 mm, and the height is 1 - 2 mm. The bottom surface of the U-shaped groove is lower at the front and higher at the rear, with an angle of 10 - 20° with the surface of the straight section. The two leading edge curves of the U-shaped groove are both spline curves connecting the vertex and the trailing edge endpoints. In the top view direction, the distance from the vertex to the trailing edge of the leading edge curve within the surface of the straight section is 23 - 28 mm, and the distance from the vertex to the trailing edge of the leading edge curve within the bottom surface is 20 - 25 mm.

[0009] Compared with the prior art, the advantages and beneficial effects of the present invention are as follows:

[0010] First, it has good flame stabilization performance. The conventional strut flame stabilizer generates a von Kármán vortex street type recirculation vortex, whose recirculation vortex shedding frequency is relatively high, the stability of the recirculation vortex is poor, and combustion instability problems are likely to occur. Moreover, the distance from the fuel injection to the recirculation zone is very short, and the fuel evaporation and mixing are insufficient, which easily leads to unstable combustion. After arranging U-shaped grooves on both sides of the conventional strut flame stabilizer, a horn-shaped stagnation vortex is formed within the U-shaped grooves, which is conducive to fuel evaporation and mixing; the shedding frequency of the von Kármán vortex street type recirculation vortex behind the stabilizer also decreases significantly, and the stability of the recirculation vortex is enhanced. Therefore, the flame stabilization performance is better after arranging the U-shaped grooves.

[0011] Second, it has high combustion efficiency. After arranging U-shaped grooves on both sides of the conventional strut flame stabilizer, a horn-shaped stagnation vortex is formed within the U-shaped grooves, which is conducive to fuel evaporation and mixing; the shedding frequency of the von Kármán vortex street type recirculation vortex behind the stabilizer also decreases significantly, and the stability of the recirculation vortex is enhanced. Therefore, arranging the U-shaped grooves is conducive to obtaining more stable and efficient combustion, thereby achieving a higher combustion efficiency.

[0012] Third, the flow resistance loss is small. To achieve the same flame stabilization performance and combustion efficiency, compared with increasing the blockage width of the conventional strut flame stabilizer, arranging U-shaped grooves on both sides of the conventional strut flame stabilizer causes less flow resistance loss. Moreover, reducing the shedding frequency of the von Kármán vortex street type recirculation vortex is conducive to reducing the flow resistance loss. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 Isometric view of the strut flame stabilizer with U-shaped grooves in the present invention.

[0014] Figure 2 Side view of the strut flame stabilizer with U-shaped grooves in the present invention.

[0015] Figure 3 Top view of the strut flame stabilizer with U-shaped grooves in the present invention.

[0016] Figure 4 Front view of the strut flame stabilizer with U-shaped grooves in the present invention.

[0017] Figure 5 This is the rear view of the strut flame stabilizer with a hoof-shaped groove in the present invention.

[0018] Figure 6 Is the longitudinal section V of a conventional strut flame stabilizer X distribution.

[0019] Figure 7 Is the transverse section V of a conventional strut flame stabilizer X distribution.

[0020] Figure 8 Is the longitudinal section V of the strut flame stabilizer with a hoof-shaped groove in the present invention X distribution.

[0021] Figure 9 Is the transverse section V of the strut flame stabilizer with a hoof-shaped groove in the present invention X distribution.

[0022] Figure 10 Is the streamline of the strut flame stabilizer with a hoof-shaped groove in the present invention Figure 1 .

[0023] Figure 11 Is the streamline of the strut flame stabilizer with a hoof-shaped groove in the present invention Figure 2 .

[0024] In the drawings, 1 is the leading edge; 2 is the straight section; 3 is the V-shaped bottom surface; 4 is the hoof-shaped groove; L1 is the chord length of the strut flame stabilizer; L2 is the distance from the vertex of the leading edge curve of the hoof-shaped groove in the bottom surface of the hoof-shaped groove to the trailing edge; L3 is the distance from the vertex of the leading edge curve of the hoof-shaped groove in the surface of the straight section to the trailing edge; W1 is the width of the straight section; W2 is the height of the trailing edge of the hoof-shaped groove; H1 is the span of the strut flame stabilizer; H2 is the length of the trailing edge of the hoof-shaped groove; α is the V-shaped bottom surface angle of the strut flame stabilizer; Detailed implementation mode

[0025] The following will be combined with the attached Figures 1 to 5 drawings and embodiments to further elaborate on the present invention.

[0026] A strut flame stabilizer with a hoof-shaped groove has 3 to 5 hoof-shaped grooves 4 evenly arranged on both sides of the strut flame stabilizer. In this embodiment, it is specifically 3.

[0027] As a further improvement of the embodiment of the present invention, for the strut flame stabilizer, the chord length L1 is 90 - 150 mm, specifically 120 mm in this embodiment; the span length H1 is determined by the specific engine, specifically 180 mm in this embodiment. It is composed of a leading edge 1, a straight section 2, and a V-shaped bottom surface 3. The leading edge 1 is an elliptical surface, and the major axis dimension of the ellipse is 1.7 - 2.5 times the minor axis, specifically 1.77 times in this embodiment. The leading edge 1 is tangent and continuous with the straight section 2. The width W1 of the straight section 2 is 24 - 36 mm, specifically 26 mm in this embodiment. The included angle α of the V-shaped bottom surface 3 is 100° - 150°, specifically 120° in this embodiment.

[0028] As a further improvement of the embodiment of the present invention, for the horseshoe-shaped groove 4, its trailing edge is flush with the trailing edge of the strut flame stabilizer. The trailing edge length H2 of the horseshoe-shaped groove is 40 - 50 mm, specifically 46 mm in this embodiment; the trailing edge height w2 of the horseshoe-shaped groove is 1 - 2 mm, specifically 1 mm in this embodiment. The bottom surface of the horseshoe-shaped groove is lower at the front and higher at the rear, and the included angle with the surface of the straight section is 10 - 20°, specifically 15° in this embodiment. The two leading edge curves of the horseshoe-shaped groove are both spline curves connecting the vertex and the trailing edge endpoints. In the top view direction, the distance L3 from the vertex to the trailing edge of the leading edge curve within the surface of the straight section is 23 - 28 mm, specifically 25 mm in this embodiment; the distance L2 from the vertex to the trailing edge of the leading edge curve within the bottom surface is 20 - 25 mm, specifically 22 mm in this embodiment.

[0029] The above-described embodiments are only the preferred embodiments of the present invention, rather than an exhaustive list of all feasible embodiments of the present invention. For those of ordinary skill in the art, any obvious modifications made without departing from the principles and spirit of the present invention should be considered to be included within the protection scope of the claims of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the said claims.

Claims

1. A strut flame stabilizer with a hoof-shaped groove, characterized in that, Three to five horseshoe-shaped grooves (4) are evenly arranged on both side surfaces of the strut flame stabilizer; the chord length of the strut flame stabilizer is 90 - 150 mm, and the span length is determined by the specific engine. The strut flame stabilizer is composed of a leading edge (1), a straight section (2), and a V-shaped bottom surface (3). The leading edge (1) is an elliptical surface, and the major axis dimension of the ellipse is 1.7 - 2.5 times that of the minor axis. The leading edge (1) is tangent and continuous with the straight section (2). The width of the straight section (2) is 24 - 36 mm, and the included angle of the V-shaped bottom surface (3) is 100° - 150°. The trailing edge of the horseshoe-shaped groove (4) is flush with the trailing edge of the strut flame stabilizer. The length of the trailing edge of the horseshoe-shaped groove (4) is 40 - 50 mm, and the height of the trailing edge of the horseshoe-shaped groove (4) is 1 - 2 mm. The bottom surface of the horseshoe-shaped groove (4) is lower at the front and higher at the rear. The included angle between the bottom surface of the horseshoe-shaped groove (4) and the surface of the straight section (2) is 10 - 20°. The two leading edge curves of the horseshoe-shaped groove (4) are both spline curves connecting the vertex and the trailing edge endpoints. In the top view direction, the distance from the vertex to the trailing edge of the leading edge curve within the surface of the straight section (2) is 23 - 28 mm, and the distance from the vertex to the trailing edge of the leading edge curve within the bottom surface of the horseshoe-shaped groove (4) is 20 - 25 mm.

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