Air film cooling structure of high-temperature hot end component of aero-engine

Abstract

The application discloses an air film cooling structure of an aero-engine high-temperature hot end component, wherein the air film hole adopts an elliptical annular expansion slit air film hole, the elliptical annular slit hole comprises an inner ring side wall and an outer ring side wall, the long axis directions of the two are basically perpendicular to the main flow direction of the high-temperature gas main flow, the short axis directions of the two are basically parallel to the main flow direction of the high-temperature gas main flow, and a rib plate extending from an air inlet end to an air outlet end is arranged between the inner ring side wall and the outer ring side wall. The structure aims at the technical problem that the existing cylindrical air film hole is easy to form a kidney-shaped vortex at the outlet, thereby causing the cold gas to be lifted, the coverage area of the air film to be reduced and the cooling effect to be deteriorated, the elliptical annular expansion air film hole provided with the rib plate is used to construct opposite kidney-shaped vortices in the rotating direction on the wall surface of the hot end component to be cooled, so that the effect of the kidney-shaped vortex is inhibited, the purpose of enhancing the air film adhesion is achieved, and the structure is simple and has wide applicability.

Description

Technical Field

[0001] This invention belongs to the field of cooling technology for hot-end components of aero-engines, and relates to a film cooling structure for high-temperature hot-end components of aero-engines. Specifically, it relates to a cooling structure for hot-end components of aero-engines with elliptical annular expansion film holes and ribs installed in the elliptical annular expansion film holes. This structure can form an anti-kidney vortex at the outlet of the film hole, which is opposite to the rotation direction of the kidney vortex. This can counteract or partially counteract the effect of the kidney vortex, enhance the adhesion ability of the film, improve the cooling effect, and the structure is relatively simple with no significant increase in aerodynamic losses, and has broad application prospects. Background Technology

[0002] Film cooling technology is widely used in existing technologies to protect high-temperature hot-end components of aero engines, such as turbine blades, combustion chambers, and exhaust nozzles, ensuring their normal operation in high-temperature gas environments. This helps to withstand the strong heat load generated by the high-temperature gas and prevent creep or damage due to high temperatures. With the increasing temperature of engine gas, the inlet temperature of turbines in advanced civil high-bypass aero engines has exceeded 2000K. Cooling high-temperature hot-end components of aero engines has become a key technology for developing high-performance gas turbine engines. Although film cooling requires more cooling air and leads to a decrease in engine cycle thermal efficiency, modern high-performance gas turbine engines almost universally adopt film cooling technology, and the amount of cooling air used is gradually increasing. This is because the performance benefits of increasing gas temperature far outweigh the performance degradation caused by the increased cooling air consumption.

[0003] In film cooling (FSL) technology, low-temperature cold gas enters the high-temperature mainstream region along a specific injection direction through film orifices or slits opened on the wall of the hot-end component. Due to the pressure of the high-temperature mainstream fluid and the friction of the wall, the low-temperature cold gas covers the surface of the hot-end component, isolating the mainstream high-temperature combustion gas from the component wall, weakening the heat exchange process between the mainstream combustion gas and the component wall, thereby reducing the temperature of the hot-end component and preventing corrosion of the hot-end component surface by impurities in the high-temperature combustion gas. FSL is one of the main cooling methods for high-temperature hot-end components in gas turbines due to its high cooling efficiency and flexible arrangement. The efficiency of FSL is not only affected by flow parameters such as the air-to-air ratio, the tightness ratio, and the mainstream Reynolds number, but also closely related to the geometric parameters of the film orifices. Currently, in the optimization research of the geometry of film orifices, researchers have conducted extensive studies on composite angle film orifices and irregularly shaped orifices. Research results show that compared with traditional cylindrical film orifices, improving the shape of the film orifices can effectively improve the film cooling effect. This is mainly because during the mixing of the cylindrical film cooling jet with the mainstream, the temperature and velocity difference between the jet and the mainstream creates a kidney-shaped vortex. This forces the low-temperature cooling jet to detach from the wall, while the high-temperature mainstream combustion jet re-attaches to the wall, reducing the film cooling area and decreasing the film cooling effect. Improving the shape of the film cooling orifice, to some extent, increases the outlet area, reduces the jet outlet velocity, and weakens the effect of the kidney-shaped vortex, thereby improving the film cooling effect. However, irregularly shaped orifices and other film cooling orifice structures are relatively complex, difficult to manufacture, and costly. Furthermore, they have a certain impact on the mainstream aerodynamic performance of the blade surface and increase aerodynamic losses. Summary of the Invention

[0004] (I) Purpose of the Invention

[0005] To address the aforementioned deficiencies and shortcomings of existing technologies, the present invention aims to propose a film cooling structure for high-temperature hot-end components of aero-engines. This structure employs elliptical annular expansion film cooling holes with ribbed structures within them. This design addresses the technical problem of existing cylindrical film cooling holes easily forming kidney-shaped vortices at the outlet, leading to the lifting of cool air, reduced film coverage, and deterioration of cooling effect. By using ribbed elliptical annular expansion film cooling holes to construct anti-kidney-shaped vortices with opposite rotation directions on the wall surface to be cooled of the hot-end component, the effect of kidney-shaped vortices is suppressed, thereby enhancing film adhesion to the wall. This design offers the advantages of simple structure and wide applicability.

[0006] (II) Technical Solution

[0007] To achieve its inventive purpose and solve its technical problems, the technical solution adopted by this invention is as follows:

[0008] A film cooling structure for a high-temperature hot-end component of an aero-engine, wherein a plurality of film cooling holes are arranged on the substrate of the high-temperature hot-end component to be cooled, wherein the inlet end of each film cooling hole is formed on the low-temperature side surface of the substrate to be cooled, and the outlet end is formed on the high-temperature side surface of the substrate to be cooled, the film cooling hole is used to inject a low-temperature cooling jet into the high-temperature combustion gas stream and form a cooling film covering the low-temperature side surface of the substrate to be cooled, characterized in that...

[0009] Each of the aforementioned film cooling holes has an elliptical annular slit-like cross-section. The elliptical annular slit-like hole includes an inner annular sidewall located radially inward and an outer annular sidewall located radially outward. The major axes of the inner and outer annular sidewalls are substantially perpendicular to the mainstream direction of the high-temperature gas flow, and their minor axes are substantially parallel to the mainstream direction of the high-temperature gas flow. At the outlet end, the major axis radius of the outer annular sidewall is a1, and the minor axis radius is b1; the major axis radius of the inner annular sidewall is a2, and the minor axis radius is b2. At the inlet end, the major axis radius of the outer annular sidewall is a3, and the minor axis radius is b3; the major axis radius of the inner annular sidewall is a4, and the minor axis radius is b4. Furthermore, a4 ≤ a2, b4 ≤ b2, a3 ≤ a1, and b3 ≤ b1.

[0010] Each of the aforementioned air film cooling holes is provided with a rib plate located between its inner ring sidewall and outer ring sidewall and extending from the air inlet end to the air outlet end. The two ends of the rib plate in its length direction are respectively flush with the low temperature side surface and the high temperature side surface of the substrate to be cooled, and the two ends of the rib plate in its width direction are respectively perpendicular to the inner ring sidewall and the outer ring sidewall.

[0011] Each of the aforementioned air film cooling holes is arranged at an angle on the wall substrate to be cooled, and the angle θ between its center line and the tangent direction of the wall substrate to be cooled is an acute angle. Furthermore, the inner and outer ring sidewalls of each of the aforementioned air film cooling holes are both in an expanding shape with an expansion angle α from their air inlet end to their air outlet end.

[0012] In a preferred embodiment of the present invention, the thickness of the stiffener gradually changes along its length, with a thickness of f at the air inlet and e at the air outlet, where e is greater than f. The stiffener is mainly used to connect the air film pores and the substrate. Since the air film pores are expansion-shaped, the gradual thickening of the stiffener is to ensure the strength of the annular air film pores.

[0013] In a further preferred embodiment of the present invention, the thickness f of the air inlet end plate of the rib plate is b3-b4, and the thickness e of the air outlet end plate is b1-b2.

[0014] In a preferred embodiment of the present invention, the angle θ between the centerline of each of the air film cooling holes and the tangent direction of the wall surface of the substrate 1 to be cooled is in the range of 20 to 60°.

[0015] In a preferred embodiment of the present invention, the expansion angle α between the inner and outer ring sidewalls of each of the air film cooling holes, from their inlet to outlet, ranges from 0 to 6°.

[0016] In a preferred embodiment of the present invention, the gas film cooling holes are arranged in an array on the substrate of the wall to be cooled, and the hole spacing P between two adjacent gas film cooling holes in the direction perpendicular to the mainstream of the high-temperature gas flow is between 3a1 and 6a1.

[0017] The working principle of the film cooling structure for the high-temperature hot-end component of the aero-engine of the present invention is as follows:

[0018] The present invention relates to a film cooling structure for high-temperature hot-end components of aero-engines. This structure addresses the technical problem that existing cylindrical film cooling orifices easily form kidney-shaped vortices at the outlet, leading to the lifting of cold air, reduced film coverage area, and deterioration of cooling effect. The structure optimizes the geometry of the film cooling orifice by replacing the commonly used cylindrical one with an elliptical annular expansion slit film cooling orifice. The elliptical annular expansion slit film cooling orifice is equipped with a rib structure. Since the major axis of the inner and outer ring sidewalls of the elliptical annular expansion slit film cooling orifice is substantially perpendicular to the mainstream direction of the high-temperature gas flow, and the minor axis is substantially parallel to the mainstream direction of the high-temperature gas flow, the size of the film cooling orifice perpendicular to the mainstream direction is larger than the size parallel to the mainstream direction. This increases the lateral coverage width and area of ​​the film cooling formed on the surface of the substrate to be cooled, thereby improving the film cooling effect to a certain extent. On the other hand, the flow cross-sectional area of ​​existing cylindrical orifices is fixed, making precise flow control impossible. In contrast, the elliptical annular slit allows for adjustment of the flow cross-sectional area by modifying the major and minor axes of its ellipse, enabling better control of the cooling gas flow rate and velocity. The elliptical annular slit also reduces gas flow resistance and inertial drag, improving ejection velocity and cooling efficiency. Furthermore, the elliptical annular slit design incorporates an expansion angle, allowing the cooling gas to diffuse at the film gas outlet, further reducing velocity and pressure, and enhancing ejection velocity and cooling efficiency. Simultaneously, the elliptical annular slit design increases turbulence intensity around the film gas orifice, enhancing gas mixing and improving cooling performance. Additionally, the expansion angle stabilizes gas flow, reducing flow disturbance and improving film gas stability and cooling effect.

[0019] Finally, it's important to emphasize that incorporating ribs within the film cooling orifice can induce opposite-rotational reniform vortices on the cooling wall surface of the hot-end component, thus suppressing the effect of reniform vortices. The ribs guide the flow direction towards curvature, creating a rotating flow that counteracts the reniform vortex's influence. This reduces the longitudinal height (m1) and increases the lateral length (n1) of the reniform vortex, thereby increasing the film cooling coverage width, improving film stability and cooling efficiency, and enhancing film adhesion to the wall. Furthermore, the presence of ribs improves gas mixing, allowing the cooling gas to mix more thoroughly with the surrounding flow field, further enhancing the cooling effect.

[0020] (III) Technical Effects

[0021] Compared with the prior art, the film cooling structure for high-temperature hot-end components of aero-engines provided by this invention has the following characteristics and significant technical effects:

[0022] (1) Simple structure: The air film cooling structure for high-temperature hot end components of aero-engines provided by the present invention is an elliptical annular expansion air film hole, which does not rely on any existing air film hole structure. The overall structure is relatively simple and does not have high requirements for processing technology.

[0023] (2) Good adjustability: The air film cooling structure of the high-temperature hot end component of the aero-engine provided by the present invention can change the structure of the kidney vortex and the anti-kidney vortex by adjusting the major axis and minor axis of the ellipse, so as to obtain good cooling effect on different applications.

[0024] (3) Wide range of applications: The air film cooling structure for high-temperature hot end components of aero engines provided by the present invention can be used for hot end components of aero engines such as turbine guide vanes, moving blades, and combustion chambers to achieve efficient cooling for different needs.

[0025] (4) Significant improvement in cooling effect: The air film cooling structure for high-temperature hot-end components of aero-engines provided by the present invention suppresses the negative effects of the kidney vortex from the source, resulting in a significant improvement in cooling effect. Attached Figure Description

[0026] Figure 1 This is a top view of the film cooling structure for the high-temperature hot-end components of an aero-engine provided by the present invention.

[0027] Figure 2 This is a cross-sectional view of the elliptical annular expansion film pore in this invention.

[0028] Figure 3 This is a schematic diagram of a kidney-shaped vortex structure formed by an existing cylindrical air film aperture.

[0029] Figure 4 This is a schematic diagram of the kidney-shaped vortex and anti-kidney-shaped vortex structure formed by the elliptical annular expansion air film holes of the present invention.

[0030] Explanation of reference numerals in the attached figures:

[0031] 1-The substrate of the wall surface to be cooled for the high-temperature hot end component of an aero-engine; 2-Elliptical annular expansion film ventilation hole; 3-Firming plate; 4-Inner ring sidewall; 5-Outer ring sidewall; 6-Inlet end; 7-Outlet end; 8-Main stream; 9-Jet; 10-Kidney-shaped vortex formed by existing cylindrical film ventilation holes; 11-Kidney-shaped vortex formed by the elliptical annular expansion film ventilation hole of the present invention; 12-Anti-kidney-shaped vortex of elliptical annular expansion film ventilation hole; e-Plate thickness at the outlet end of the rig; f-Plate thickness at the inlet end of the rig; a1-Major axis radius of the outlet end of the outer ring sidewall; b1-Minor axis radius of the outlet end of the outer ring sidewall; a2-Major axis radius of the outlet end of the inner ring sidewall; b2-Minor axis radius of the outlet end of the inner ring sidewall; a3-Major axis radius of the inlet end of the outer ring sidewall; b3-Minor axis radius of the inlet end of the outer ring sidewall; a4-Inner ring... The major axis radius of the side wall inlet end, b4 - minor axis radius of the inner ring side wall inlet end, θ - angle between the center line of the film cooling hole and the tangent direction of the wall surface of the substrate to be cooled, α - expansion angle between the inner ring side wall and the outer ring side wall from their inlet end to their outlet end, P - hole spacing between two adjacent film cooling holes in the direction perpendicular to the mainstream of the high-temperature gas flow, m1 - height dimension of the kidney-shaped vortex formed by the existing cylindrical film cooling hole, n1 - width dimension of the kidney-shaped vortex formed by the existing cylindrical film cooling hole, m2 - height dimension of the kidney-shaped vortex formed by the elliptical annular expansion film cooling hole, n2 - width dimension of the kidney-shaped vortex formed by the elliptical annular expansion film cooling hole, m3 - height dimension of the anti-kidney-shaped vortex formed by the elliptical annular expansion film cooling hole, n3 - width dimension of the anti-kidney-shaped vortex formed by the elliptical annular expansion film cooling hole. Detailed Implementation

[0032] To better understand the present invention, the following embodiments further illustrate the content of the invention, so that the advantages and features of the invention can be more easily understood by those skilled in the art. It should be noted that the following descriptions are merely preferred embodiments of the present invention, but the content of the invention is not limited to the following embodiments. In fact, various modifications and variations can be made to the present invention without departing from the scope or spirit of the invention, which will be apparent to those skilled in the art. For example, features shown or described as part of one embodiment can be used with another embodiment to produce yet another embodiment. Therefore, it is intended that such modifications and variations be included within the scope of the appended claims and their equivalents.

[0033] like Figures 1-2As shown, the present invention provides a film cooling structure for a high-temperature hot-end component of an aero-engine. A plurality of film cooling holes 2 are arranged on the substrate 1 of the high-temperature hot-end component of the aero-engine. The inlet end 6 of each film cooling hole 2 is formed on the low-temperature side surface of the substrate 1 and the outlet end 7 is formed on the high-temperature side surface of the substrate 1. The film cooling hole 2 is used to inject a low-temperature cooling jet 9 into the high-temperature combustion stream 8 and form a cooling film covering the low-temperature side surface of the substrate 1.

[0034] Each film cooling hole 2 has an elliptical annular slit in cross-section. The elliptical annular slit includes an inner annular sidewall 4 located radially inward and an outer annular sidewall 5 located radially outward. The major axis of the inner annular sidewall 4 and the outer annular sidewall 5 is substantially perpendicular to the mainstream direction of the high-temperature gas flow 8, and the minor axis is substantially parallel to the mainstream direction of the high-temperature gas flow 8. At the outlet end, the major axis radius of the outer annular sidewall 5 is a1 and the minor axis radius is b1, while the major axis radius of the inner annular sidewall 4 is a2 and the minor axis radius is b2. At the inlet end, the major axis radius of the outer annular sidewall 5 is a3 and the minor axis radius is b3, while the major axis radius of the inner annular sidewall 4 is a4 and the minor axis radius is b4. Furthermore, a4≤a2, b4≤b2, a3≤a1, and b3≤b1.

[0035] Each film cooling hole 2 is provided with a stiffener 3 located between its inner ring sidewall 4 and outer ring sidewall 5, extending from the air inlet end to the air outlet end. The two ends of the stiffener 3 in its length direction are flush with the low-temperature side surface and high-temperature side surface of the substrate 1 to be cooled, respectively, and the two ends of the stiffener 3 in its width direction are perpendicular to the inner ring sidewall 4 and outer ring sidewall 5, respectively. Along its length direction, the thickness of the stiffener 3 gradually changes, with a thickness of f at the air inlet end and e at the air outlet end, where e > f. The thickness f at the air inlet end is b3-b4, and the thickness at the air outlet end is eb1-b2. The stiffener mainly serves to connect the film cooling hole and the substrate. Since the film cooling hole is expansion-shaped, the gradual thickening of the stiffener ensures the strength of the annular film cooling hole.

[0036] Each film cooling hole 2 is set on the wall substrate 1 to be cooled in an inclined state, and the angle θ between its center line and the tangent direction of the wall surface of the wall substrate 1 to be cooled is an acute angle. Furthermore, the inner ring sidewall 4 and the outer ring sidewall 5 of each film cooling hole 2 are both in an expansion type with an expansion angle α from its air inlet end to its air outlet end.

[0037] In a preferred embodiment of the present invention, the angle θ between the centerline of each film cooling hole 2 and the tangent direction of the wall surface of the substrate 1 to be cooled ranges from 20° to 60°. The expansion angle α between the inner ring sidewall 4 and the outer ring sidewall 5 of each film cooling hole 2 from its inlet end to its outlet end ranges from 0° to 6°. The film cooling holes 2 are arranged in an array on the substrate 1 to be cooled, and the hole spacing P between two adjacent film cooling holes 2 in the direction perpendicular to the mainstream of the high-temperature gas flow 8 is between 3a1 and 6a1.

[0038] More specifically, Figure 1 The image shown is a top view (xz plane) of the film cooling structure for the high-temperature hot-end component of an aero-engine according to the present invention. The dashed lines represent the internal structure of the holes. It can be seen that, based on the traditional cylindrical film cooling hole, the structure of the present invention is an elliptical annular slit film cooling hole. The elliptical annular slit film gas orifice includes an inner annular sidewall 4 located radially inward and an outer annular sidewall 5 located radially outward. The major axes of the inner and outer annular sidewalls 4 and 5 are substantially perpendicular to the mainstream direction of the high-temperature gas flow 8, and the minor axes are substantially parallel to the mainstream direction of the high-temperature gas flow 8. The major axis radius of the inner annular sidewall 4 at the inlet end is a4, and the minor axis radius is b4; the major axis radius of the outer annular sidewall 5 at the inlet end is a3, and the minor axis radius is b3; the major axis radius of the inner annular sidewall 4 at the outlet end is a2, and the minor axis radius is b2; the major axis radius of the outer annular sidewall 5 at the outlet end is a1, and the minor axis radius is b1; wherein, a4≤a2, b4≤b2, a3≤a1, and b3≤b1. The annular slit air film vent of the present invention is not a 360° full ring, but has a stiffening plate 3 between the inner ring sidewall 4 and the outer ring sidewall 5, which is connected to the base 1. The thickness of the stiffening plate 3 at the air inlet end is f, and the thickness at the air outlet end is e. Along its length direction, the thickness of the stiffening plate 3 gradually changes, that is, e≠f. The air film cooling holes 2 are arranged in an array on the base 1 of the wall surface to be cooled. The hole spacing between two adjacent air film cooling holes 2 in the mainstream direction perpendicular to the mainstream of the high temperature gas flow 8 is P.

[0039] Figure 2 The figure shown is a cross-sectional view (yz section) of the elliptical annular expansion film cooling hole of the present invention. The angle between the center line of the elliptical annular expansion film cooling hole and the tangent direction of the wall surface of the substrate 1 to be cooled is θ (20-60°). The elliptical ring is expanded from the air inlet end 6 to the air outlet end 7. The inner ring sidewall 4 and the outer ring sidewall 5 of each film cooling hole 2 have an expansion angle α from its air inlet end to its air outlet end. The expansion angle is α (0-6°).

[0040] Figure 3 The existing cylindrical air film jet and the mainstream form a kidney-shaped vortex 10 on the xy section. This vortex 10 easily causes the air film to detach from the wall, weakening the cooling effect. Figure 4 The kidney-shaped vortex 11 and the anti-kidney-shaped vortex 12 formed by the elliptical annular expansion air film holes of the present invention.

[0041] contrast Figure 3 , 4 It can be seen that the improved film cooling structure of this invention brings obvious technical effects: The film cooling structure of the high-temperature hot end component of the aero-engine of this invention addresses the technical problem that existing cylindrical film cooling holes easily form kidney-shaped vortices at the outlet, resulting in the lifting of cold air, reduction of film coverage area, and deterioration of cooling effect. The geometry of the film cooling hole is optimized, and the film cooling hole adopts an elliptical annular expansion slit film cooling hole instead of the commonly used cylindrical film cooling hole. The elliptical annular expansion slit film cooling hole is provided with a rib structure. Since the major axis direction of the inner ring sidewall 4 and the outer ring sidewall 5 of the elliptical annular expansion slit film cooling hole is basically perpendicular to the mainstream direction of the high-temperature gas mainstream 8, and the minor axis direction is basically parallel to the mainstream direction of the high-temperature gas mainstream 8, that is, the size of the film cooling hole in the direction perpendicular to the mainstream direction is larger than the size in the direction parallel to the mainstream direction, which increases the lateral coverage width and coverage area of ​​the film cooling formed on the surface of the substrate to be cooled, thus improving the film cooling effect to a certain extent. On the other hand, the flow cross-sectional area of ​​existing cylindrical orifices is fixed, making precise flow control impossible. In contrast, the elliptical annular slit allows for adjustment of the flow cross-sectional area by modifying the major and minor axes of its ellipse, enabling better control of the cooling gas flow rate and velocity. The elliptical annular slit also reduces gas flow resistance and inertial drag, improving ejection velocity and cooling efficiency. Furthermore, the elliptical annular slit design incorporates an expansion angle, allowing the cooling gas to diffuse at the film gas outlet, further reducing velocity and pressure, and enhancing ejection velocity and cooling efficiency. Simultaneously, the elliptical annular slit design increases turbulence intensity around the film gas orifice, enhancing gas mixing and improving cooling performance. Additionally, the expansion angle stabilizes gas flow, reducing flow disturbance and improving film gas stability and cooling effect.

[0042] It is also important to emphasize that installing ribs in the film cooling orifice can induce anti-kidney vortices with opposite rotation directions on the wall surface to be cooled in the hot end component, thus suppressing the effect of kidney vortices. The function of the ribs is to guide the flow direction to bend, thereby forming a rotating flow that corresponds to the kidney vortex, counteracting its influence. This reduces the longitudinal height m1 and increases the lateral length n1 of the kidney vortex, increasing the width of the film cooling coverage, improving the stability and cooling effect of the film, and ultimately enhancing film adhesion to the wall. Furthermore, the presence of ribs can improve gas mixing, allowing the cooling gas to mix more thoroughly with the surrounding flow field, further enhancing the cooling effect.

[0043] Finally, it should be noted that the film cooling structure for high-temperature hot-end components of aero-engines provided by this invention has been verified through numerical simulation of film cooling characteristics under different parameters. Compared with a simple cylindrical orifice, the kidney-shaped vortex is significantly suppressed, and the film adhesion capability is greatly improved. Typical operating condition analysis shows that the cooling efficiency is improved by an average of 12%. Furthermore, this structure is simple, has wide applicability, and is a promising new cooling structure.

[0044] The objectives of this invention have been fully and effectively achieved through the above embodiments. All equivalent or simple variations made to the structures, features, and principles described in this patent concept are included within the protection scope of this patent. Those skilled in the art can make various modifications or additions to the described specific embodiments or use similar methods to replace them, as long as they do not deviate from the structure of this invention or exceed the scope defined in these claims, all of which should fall within the protection scope of this invention.

Claims

1. A film cooling structure for a high-temperature hot-end component of an aero-engine, wherein a plurality of film cooling holes are arranged on the substrate of the high-temperature hot-end component of the aero-engine, the inlet end of each film cooling hole is formed on the low-temperature side surface of the substrate of the substrate of the substrate of the substrate of the aero-engine, and the outlet end is formed on the high-temperature side surface of the substrate of the substrate of the substrate of the aero-engine, the film cooling hole is used to inject a low-temperature cooling jet into the high-temperature combustion gas stream and form a cooling film covering the low-temperature side surface of the substrate of the substrate of the substrate of the aero-engine, characterized in that, Each of the aforementioned film cooling holes has an elliptical annular slit-like cross-section. The elliptical annular slit-like hole includes an inner annular sidewall located radially inward and an outer annular sidewall located radially outward. The major axis of the inner and outer annular sidewalls is perpendicular to the mainstream direction of the high-temperature gas flow, and their minor axis is parallel to the mainstream direction of the high-temperature gas flow. At the outlet end, the major axis radius of the outer annular sidewall is a1, and the minor axis radius is b1; the major axis radius of the inner annular sidewall is a2, and the minor axis radius is b2. At the inlet end, the major axis radius of the outer annular sidewall is a3, and the minor axis radius is b3; the major axis radius of the inner annular sidewall is a4, and the minor axis radius is b4. Furthermore, a4 ≤ a2, b4 ≤ b2, a3 ≤ a1, and b3 ≤ b1. Each of the aforementioned air film cooling holes is provided with a rib plate located between its inner ring sidewall and outer ring sidewall and extending from the air inlet end to the air outlet end. The two ends of the rib plate in its length direction are respectively flush with the low temperature side surface and the high temperature side surface of the wall surface substrate to be cooled, and the two ends of the rib plate in its width direction are respectively perpendicular to the inner ring sidewall and the outer ring sidewall. Each of the aforementioned air film cooling holes is disposed at an angle on the substrate of the wall to be cooled, with the angle between its centerline and the tangent direction of the wall surface of the substrate being cooled being... θ The angle is acute, and the inner and outer ring sidewalls of each of the aforementioned film cooling holes form an expansion angle from their inlet to outlet ends. α Expansion type; Along its length, the thickness of the rib gradually changes, with a thickness of f at the air inlet and e at the air outlet, where e > f; The thickness f of the rib at the air inlet end is b3-b4, and the thickness e of the rib at the air outlet end is b1-b2; The air film cooling holes are arranged in an array on the substrate of the wall to be cooled, and the hole spacing P between two adjacent air film cooling holes in the mainstream direction perpendicular to the mainstream of the high temperature gas is between 3a1 and 6a1.

2. The film cooling structure for high-temperature hot-end components of an aero-engine according to claim 1, characterized in that, The angle between the centerline of each of the aforementioned film cooling holes and the tangent direction of the wall surface of the substrate to be cooled. θ The numerical range is between 20 and 60°.

3. The film cooling structure for high-temperature hot-end components of an aero-engine according to claim 1, characterized in that, The expansion angle between the inner and outer annular sidewalls of each of the aforementioned film cooling holes from its inlet end to its outlet end. α The numerical range is between 0 and 6°.

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