A strut flame stabilizer with double wavy ribs

Abstract

The present invention relates to a strut flame stabilizer with double wavy ribs. The strut flame stabilizer is composed of a leading edge, a straight section, and a V-shaped bottom surface. Front wavy ribs and rear wavy ribs are arranged on both side surfaces of the straight section. The advantages and beneficial effects achieved by the present invention are as follows: When the afterburner adopts the strut flame stabilizer with double wavy ribs, it has good flame stabilization performance, high combustion efficiency, and small flow resistance loss.

Description

Technical Field

[0001] The present invention relates to a strut flame stabilizer with double wavy ribs, which can be used in an integrated afterburner of a high thrust-to-weight ratio aeroengine, belonging to the field of aviation technology. Background Art

[0002] The new generation of afterburning turbofan engines pursues a high thrust-to-weight ratio. In terms of the afterburner, it is required that the components are simple, the cold flow resistance loss is low, the proportion of the afterburning section length is small, and at the same time the afterburning efficiency is high. The afterburner uses a flame stabilizer to stabilize the flame for combustion. The performance of the flame stabilizer is a decisive factor affecting the performance of the afterburner. Most of the new generation of afterburning turbofan engines adopt an integrated afterburner with an integrated design of a fairing strut and a flame stabilizer. However, the conventional strut flame stabilizer generates a von Karman vortex street type recirculation vortex, and its recirculation vortex stability is poor, which will lead to locally unstable combustion.

[0003] Due to the small proportion of the afterburning section length, the distance from the fuel injection to the trailing edge of the flame stabilizer becomes correspondingly smaller. Before being ignited, the fuel atomization, evaporation and mixing are not sufficient, which is likely to lead to unstable combustion. After being superimposed 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 exit becomes correspondingly smaller, the combustion section becomes shorter, and the flame in the recirculation zone behind the flame stabilizer cannot spread across the entire combustion chamber laterally in time. Part of the oil-gas mixture is not fully burned, and part of the oil-gas mixture is directly discharged without participating in combustion, thus seriously affecting the afterburning efficiency. Summary of the Invention

[0004] The purpose of the present invention is to provide a strut flame stabilizer with double wavy ribs, and front and rear double wavy ribs are arranged on both sides of the strut flame stabilizer to improve the flame stability, reduce the flow loss and increase the combustion efficiency.

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

[0006] A strut flame stabilizer with double wavy ribs is provided with front wavy ribs and rear wavy ribs on both sides of the strut flame stabilizer.

[0007] Furthermore, for the strut flame stabilizer, the chord length is 90 - 150 mm, the span length is determined by the specific engine, and it is composed of a leading edge, a straight section and a V-shaped bottom surface. The leading edge is an elliptical surface, and the major axis dimension of the ellipse is 1.5 - 2.2 times that of the minor axis. The leading edge is tangent and continuous with the straight section. The width of the straight section is 24 - 36 mm, and the included angle of the V-shaped bottom surface is 100° - 150°.

[0008] Furthermore, the front wavy rib and the rear wavy rib have the same shape, with a wall thickness of 1.2 - 2 mm. They exhibit wavy geometric features in the front-back direction and at the upper edge. Both the front-back waviness and the upper-edge waviness contain 3 - 5 wavelengths, starting and ending at the wave crest positions. The waviness (front-back waviness and upper-edge waviness) is obtained by rounding the corners of the peaks and valleys of the zigzag waves. The amplitude of the front-back zigzag waves is 6 - 15 mm, the fillet radius of the front-back waviness is 15 - 26 mm, the height of the upper-edge zigzag waves is 4 - 7 mm, the fillet radius of the upper-edge waviness is 40 - 80 mm. The chordwise distance from the midline of the front-back waves of the rear wavy rib to the trailing edge of the strut flame stabilizer is 15 - 25 mm, and the distance between the midlines of the front-back waves of the front wavy rib and the rear wavy rib is 12 - 18 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, and the stability of this recirculation vortex is relatively poor, making it prone to combustion instability problems. After arranging double wavy ribs on both sides of the conventional strut flame stabilizer, a K-H type recirculation vortex is generated, and the stability of the recirculation vortex is enhanced. The double vortices behind the double wavy ribs are beneficial to the evaporation and mixing of fuel, facilitating stable and efficient combustion. The wavy geometric features of the double wavy ribs make the fuel more concentrated in the wake region of the wave valley relative to the wake region of the wave crest, and the fuel content along the span of the flame stabilizer is distributed in a wavy pattern, which is conducive to broadening the flame stabilization range. Therefore, better flame stabilization performance can be obtained.

[0011] Second, it has high combustion efficiency. After arranging double wavy ribs on both sides of the conventional strut flame stabilizer, a K-H type recirculation vortex is generated, and the stability of the recirculation vortex is enhanced. The double vortices behind the double wavy ribs are beneficial to the evaporation and mixing of fuel, and the wavy geometric features of the double wavy ribs make the fuel more concentrated in the wake region of the wave valley relative to the wake region of the wave crest, and the fuel content along the span of the flame stabilizer is distributed in a wavy pattern. These are conducive to obtaining stable and efficient combustion. Therefore, higher combustion efficiency can be obtained.

[0012] Third, the flow resistance loss is small. To achieve the same flame stabilization performance and combustion efficiency, compared with increasing the blockage thickness of the conventional strut flame stabilizer, arranging double wavy ribs on both sides of the conventional strut flame stabilizer causes less flow resistance loss. Moreover, replacing the von Kármán vortex street type recirculation vortex with a K-H type recirculation vortex is beneficial to reducing the flow resistance loss. Therefore, the flow resistance loss is smaller. Description of the Drawings

[0013] Figure 1 It is an isometric view of the strut flame stabilizer with double wavy ribs in the present invention.

[0014] Figure 2Side view of the splitter plate flame stabilizer with double wavy ribs in the present invention.

[0015] Figure 3 Top view of the splitter plate flame stabilizer with double wavy ribs in the present invention.

[0016] Figure 4 Front view of the splitter plate flame stabilizer with double wavy ribs in the present invention.

[0017] Figure 5 Rear view of the splitter plate flame stabilizer with double wavy ribs in the present invention.

[0018] Figure 6 Longitudinal section V X distribution of the splitter plate flame stabilizer with double wavy ribs in the present invention.

[0019] Figure 7 Transverse section V X distribution of the splitter plate flame stabilizer with double wavy ribs in the present invention.

[0020] Figure 8 Flow line Figure 1 of the splitter plate flame stabilizer with double wavy ribs in the present invention.

[0021] Figure 9 Flow line Figure 2 of the splitter plate flame stabilizer with double wavy ribs in the present invention.

[0022] Figure 10 Flow line Figure 3 of the splitter plate flame stabilizer with double wavy ribs in the present invention.

[0023] In the drawings, 1 is the leading edge; 2 is the straight section; 3 is the V-shaped bottom surface; 4 is the front wavy rib; 5 is the rear wavy rib; L1 is the span of the splitter plate flame stabilizer; L2 is the chord length of the splitter plate flame stabilizer; L3 is the chordwise distance from the midline of the front and rear waves of the rear wavy rib to the trailing edge of the splitter plate flame stabilizer; L4 is the distance between the midlines of the front and rear waves of the front wavy rib and the midlines of the front and rear waves of the rear wavy rib; L5 is the amplitude of the front and rear sawtooth waves of the wavy rib; W1 is the width of the straight section; H1 is the height of the sawtooth wave on the upper edge of the wavy rib; α1 is the included angle of the V-shaped bottom surface profile; R1 is the fillet radius of the front and rear waves of the wavy rib; R2 is the fillet radius of the upper edge wave of the wavy rib. Detailed implementation mode

[0024] The present invention will be further described in detail below in conjunction with the Figures 1 to 5 drawings and embodiments.

[0025] A strut flame stabilizer with double wavy ribs is provided with a front wavy rib 4 and a rear wavy rib 5 on both side surfaces of the strut flame stabilizer.

[0026] As a further improvement of the embodiment of the present invention, for the strut flame stabilizer, the chord length L2 is 90 - 150 mm, specifically 120 mm in this embodiment; the span length L1 is determined by the specific engine, specifically 180 mm in this embodiment; it consists 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 1.5 - 2.2 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 α1 of the V-shaped bottom surface 3 is 100° - 150°, specifically 120° in this embodiment.

[0027] As a further improvement of the embodiment of the present invention, the front wavy rib 4 and the rear wavy rib 5 have the same shape, with a wall thickness of 1.2 - 2 mm, specifically 1.5 mm in this embodiment. They have a wavy geometric feature in the front-back direction and at the upper edge. Both the front-back wavy and the upper-edge wavy contain 3 - 5 wavelengths, specifically 3 in this embodiment, starting and ending at the wave crest positions. The wavy shape (front-back wavy and upper-edge wavy) is obtained by rounding the wave crest and wave trough of the zigzag wave. The amplitude L5 of the front-back zigzag wave is 6 - 15 mm, specifically 12 mm in this embodiment. The fillet radius R1 of the front-back wavy is 15 - 26 mm, specifically 18 mm in this embodiment. The wave height H1 of the upper-edge zigzag wave is 4 - 7 mm, specifically 5 mm in this embodiment. The fillet radius R2 of the upper-edge wavy is 40 - 80 mm, specifically 50 mm in this embodiment. The chordwise distance L3 from the midline of the front-back wavy of the rear wavy rib 5 to the trailing edge of the strut flame stabilizer is 15 - 25 mm, specifically 20 mm in this embodiment. The distance L4 between the midlines of the front-back wavy of the front wavy rib 4 and the midlines of the front-back wavy of the rear wavy rib 5 is 12 - 18 mm, specifically 15 mm in this embodiment.

[0028] 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 double wavy ribs, characterized in that, The described strut flame stabilizer has a chord length of 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, where the major axis dimension of the ellipse is 1.5 - 2.2 times 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°. On both side surfaces of the strut flame stabilizer, there are front corrugated ribs (4) and rear corrugated ribs (5) with the same shape and a wall thickness of 1.2 - 2 mm. The front corrugated ribs (4) and the rear corrugated ribs (5) have a corrugated geometric feature in the front-rear direction and the upper edge. Both the front and rear corrugations and the upper edge corrugation contain 3 - 5 wavelengths, starting and ending at the peak positions. The front and rear corrugations and the upper edge corrugation are obtained by rounding the corners at the peaks and valleys of the sawtooth waves. The amplitude of the front and rear sawtooth waves is 6 - 15 mm, the fillet radius of the front and rear corrugations is 15 - 26 mm, the height of the upper edge sawtooth wave is 4 - 7 mm, and the fillet radius of the upper edge corrugation is 40 - 80 mm. The chordwise distance from the midline of the front and rear waves of the rear corrugated rib (5) to the trailing edge of the strut flame stabilizer is 15 - 25 mm, and the distance between the midlines of the front and rear waves of the front corrugated rib (4) and the midlines of the front and rear waves of the rear corrugated rib (5) is 12 - 18 mm.

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