V-shaped air film hole structure and turbine blade
Through the design of V-shaped air membrane pore structure, the cold air forms an inverse kidney vortex and a renal vortex pair each other, solving the problems of difficult processing and excessive material removal of existing air membrane pore structures, achieving high efficiency cooling and improvement of mechanical properties.
Patent Information
- Application Number
- CN202510684591.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-26
- Publication Date
- 2025-08-15
AI Technical Summary
The expansion section of the existing gas membrane pore structure is difficult to process, and the material removed increases, resulting in a decrease in the mechanical properties of the turbine blades.
Using a V-shaped air membrane pore structure, cold air flows out from the inner side to form an anti-renal vortex, and out from the outer side to form a renal vortex, forming an anti-renal vortex flow field. The renal vortex pairs and anti-renal vortex pairs are paired with each other, improving the cooling efficiency of the air membrane and reducing material removal.
It significantly improves the cooling efficiency and cooling effect of the air film, reduces the difficulty of processing, and reduces the impact on the mechanical properties of the turbine blades.
Smart Images
Figure CN120487256A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of aero-engines, and in particular to a V-shaped air film hole structure and a turbine blade. Background Art
[0002] To improve the thermal efficiency of aircraft engines, turbine inlet temperatures continue to rise, currently approaching 2400K. Excessively high temperatures inevitably cause turbine blade erosion, posing a serious challenge to the safe operation and lifespan of aircraft engines. This far exceeds the tolerance limits of all high-temperature alloys, making necessary cooling measures a key technology for addressing this core issue.
[0003] Film cooling is a highly efficient cooling technology currently used in aircraft engines. It utilizes a portion of the upstream compressor's bleed air to form a cooling film through discrete holes on the turbine blade surface, protecting the turbine blades from erosion by high-temperature combustion gases and ensuring safe and reliable component operation. The classic film hole shape is circular, which was once widely used due to its simple structure and ease of processing. However, the circular hole structure causes the cooling air to form a pair of kidney-shaped vortices during mixing. The movement of the kidney-shaped vortices can entrain the external high-temperature gas to the wall and promote the lifting of the cooling air from the wall, reducing the effectiveness of the film.
[0004] In order to improve the efficiency of film cooling, researchers have successively proposed a variety of new film hole structures, including expansion holes, convergent slot holes, groove holes, sister holes, cat ear holes, etc. Compared with cylindrical film holes, these hole shapes can significantly improve the efficiency of film cooling. Among them, expansion holes have been widely used in high-pressure turbine blades of aircraft engines and gas turbines. However, most of the above hole shapes are based on circular holes, and various special-shaped hole structures are realized through expansion sections. The expansion section has various complex shapes, which not only increases the difficulty of processing, but the enlarged hole structure also further increases the material removed, reducing the mechanical properties of the turbine blade. Summary of the Invention
[0005] The purpose of the present invention is to provide a V-shaped air film hole structure to solve the problem in the prior art that the expansion section of the air film hole structure is difficult to process and the increased material removed leads to a decrease in the mechanical properties of the turbine blade.
[0006] In order to solve the above problems, the present invention proposes a V-shaped air film hole structure, and the technical solution adopted is: A V-shaped air film hole structure comprises: an air film hole body, wherein the air film hole body comprises a symmetrically arranged left arm and a right arm, and the left arm and the right arm are connected by an arc segment, wherein the inner area wrapped by the left arm, the right arm and the arc segment is the inner side of the air film hole, and the outer area opposite thereto is the outer side of the air film hole, and the outer side of the air film hole is a V-shaped structure; when cold air flows out from the side position of the inner side of the air film hole, a pair of inverted kidney-shaped vortices are formed, and when cold air flows out from the side position of the outer side of the air film hole, a pair of kidney-shaped vortices are formed.
[0007] Furthermore, the V-shaped angle formed by the intersection of the outer side surface of the left arm and the outer side surface of the right arm is an opening and closing angle, and the opening and closing angle is 90°-120°.
[0008] Furthermore, the end positions of the extended ends of the left arm and the right arm are provided with a left arm end arc surface and a right arm end arc surface, so that the inner side surface of the left arm and one end of the outer side surface of the left arm are connected through the left arm end arc surface, and the inner side surface of the right arm and one end of the outer side surface of the right arm are connected through the right arm end arc surface.
[0009] Furthermore, the inner side surface of the left arm is arranged in parallel with the outer side surface of the left arm, and the inner side surface of the right arm is arranged in parallel with the outer side surface of the right arm, so that the inner side of the air film hole is a V-shaped structure.
[0010] Furthermore, the distance between the inner side surface of the left arm and the outer side surface of the left arm, and the distance between the inner side surface of the right arm and the outer side surface of the right arm are equal to the distance H1. Along the extension direction of the left arm and the right arm, the length L1 of the left arm and the right arm is 4 H1, and the radius R1 of the outer curved surface of the arc segment, the radius R2 of the inner curved surface, and the radius R3 of the left arm end curved surface and the right arm end curved surface are all equal to the distance H1.
[0011] Furthermore, the outer side surface of the left arm and the outer side surface of the right arm are symmetrically arranged, and the inner side surface of the left arm and the inner side surface of the right arm are parallelly arranged, so that the inner side of the air film hole is a U-shaped structure.
[0012] Furthermore, the arcuate surface at the end of the left arm includes an outer rounded corner and an inner rounded corner, and the outer rounded corner and the inner rounded corner are connected by a connecting plane. The outer side surface of the left arm is connected to the outer rounded corner, and the inner side surface of the left arm is connected to the inner rounded corner. The distance between the outer side surface of the left arm and the plane parallel to it and passing through the center position of the inner arcuate surface of the arc segment is H2. The radius R1 of the outer arcuate surface of the arc segment is equal to the distance H2. The radius R2 of the inner arcuate surface of the arc segment is 0.73 H2-1.2 H2. The radius R3 of the outer rounded corner is ， The radius R4 of the inner fillet is 0.67 H2.
[0013] Furthermore, in a direction parallel to the outer side surface of the left arm, the intersection line of the plane passing through the center position of the circle where the outer curved surface of the arc segment is located and the connecting plane is a first intersection line, and the distance L2 between the center line of the circle where the outer curved surface of the outer curved segment is located and the first intersection line is 4.7 H2-6 H2; in a direction perpendicular to the connecting plane, the intersection line of the plane passing through the center position of the circle where the outer curved surface of the outer curved segment is located and the connecting plane is a second intersection line, and the distance F1 between the first intersection line and the second intersection line is 4 H2-4.2 H2.
[0014] Furthermore, when the opening and closing angle is 90°, in the direction perpendicular to the connection plane, the distance F2 between the plane passing through the center position of the circle where the outer arc surface of the outer arc segment is located and the plane passing through the center position of the circle where the inner rounded corner is located is 2.1 H2; when the opening and closing angle is 120°, in the direction perpendicular to the connection plane, the distance F2 between the plane passing through the center position of the circle where the outer arc surface of the outer arc segment is located and the inner side surface of the left arm is ， is 1.2 H2.
[0015] The present invention also proposes a turbine blade, the technical solution adopted is: A turbine blade comprises the V-shaped air film hole structure described above.
[0016] Compared with the prior art, this application has the following beneficial effects: The present invention is an improved invention, which provides a V-shaped air film hole structure with a relatively simple structure. By setting the inner side of the air film hole and setting the outer side of the air film hole to a V-shaped structure, a pair of inverted kidney-shaped vortices are formed when the cold air flows out from the side position of the inner side of the air film hole, thereby constructing an inverted kidney-shaped vortex flow field. When the cold air flows out from the side position of the outer side of the air film hole, a pair of kidney-shaped vortices are formed, and the gas in the air film hole is formed into a pair of inverted kidney-shaped vortices, that is, a pair of inverted kidney-shaped vortices suppress the kidney-shaped vortex pairs in the flow field to the near-wall position of the outer area, which significantly reduces the lifting effect of the cold air; at the same time, the kidney-shaped vortex pairs and the inverted kidney-shaped vortex pairs are paired with each other, and the vortex motion promotes the lateral diffusion of the cold air, greatly improving the lateral coverage area of the air film hole, thereby improving the air film cooling efficiency and cooling effect within a wider range of working conditions; in addition, the V-shaped air film hole structure of the present invention can reduce the processing difficulty, avoid excessive material removal, improve the economy of processing, and reduce the influence of the air film hole on the mechanical properties of the turbine blade.
[0017] The V-shaped angle formed by the intersection of the outer side surfaces of the left arm and the right arm is the opening angle, and the opening angle is 90°-120°. The opening angle within this range weakens the kidney-shaped vortex pair, reduces the lift of cold air, and further effectively improves the film cooling efficiency.
[0018] The inner side of the left arm is arranged parallel to the outer side of the left arm, and the inner side of the right arm is arranged parallel to the outer side of the right arm, so that the inner side of the film hole has a V-shaped structure. The V-shaped inner side of the film hole corresponds to a simple structure, which increases the efficiency of film cooling while reducing processing difficulty and material removal.
[0019] The outer side of the left arm and the outer side of the right arm are arranged symmetrically, and the inner side of the left arm and the inner side of the right arm are arranged parallel to each other, resulting in a U-shaped structure on the inside of the air film hole. Based on the flow mixing mechanism of the V-shaped air film hole, this hole shape is further optimized, and the inner side of the air film hole is set into a U-shaped structure to strengthen the strength of the anti-kidney vortex pair, expand its influence area, and improve the adhesion of the cold air. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 This is a three-dimensional diagram of a V-shaped air film hole structure in which the inner side of the air film hole of the present invention is a V-shaped structure; Figure 2 This is a front view of a V-shaped air film hole structure of the present invention, wherein the inner side of the air film hole is a V-shaped structure; Figure 3 Schematic diagram of the vortex development of a V-shaped air film hole structure in which the inner side of the air film hole of the present invention is a V-shaped structure; Figure 4 : The downstream flow field distribution of the V-shaped air film hole structure of the present invention, in which the inner side of the air film hole is a V-shaped structure (X=3D), wherein (a) is the vorticity cloud map, and (b) is the temperature cloud map; Figure 5 The film cooling efficiency averaged in the span direction is the V-shaped film hole structure of the present invention with the inner side of the V-shaped film hole and the circular hole of the prior art; Figure 6 The figure shows the film cooling efficiency of the V-shaped film hole structure of the present invention and the circular hole structure of the prior art, wherein (a) is a circular hole and (b) is a film hole structure with a V-shaped inner side. Figure 7 This is a three-dimensional diagram of a V-shaped air film hole structure with a U-shaped structure and an opening and closing angle of 90 degrees according to the present invention; Figure 8 This is a front view of a V-shaped air film hole structure with a U-shaped structure and an opening and closing angle of 90 degrees according to the present invention; Figure 9 The film cooling efficiency averaged in the span direction between the V-shaped film hole structure with a U-shaped structure and a V-shaped film hole structure with an opening and closing angle of 90 degrees according to the present invention; Figure 10 The film cooling efficiency cloud diagram of the V-shaped film hole structure with a U-shaped opening and closing angle of 90 degrees and the V-shaped film hole structure with a V-shaped opening and closing angle of 90 degrees of the present invention, wherein (a) is the inner side of the film hole with a V-shaped structure, and (b) is the inner side of the film hole with a U-shaped structure; Figure 11 This is a three-dimensional diagram of a V-shaped air film hole structure with a U-shaped structure and an opening and closing angle of 120 degrees according to the present invention; Figure 12 This is a front view of a V-shaped air film hole structure with a U-shaped structure and an opening and closing angle of 120 degrees according to the present invention; Figure 13 The average air film cooling efficiency in the span direction of the V-shaped air film hole structure of the present invention with a U-shaped structure having an opening and closing angle of 90° and a U-shaped structure having an opening and closing angle of 120°; Figure 14 These are cloud diagrams of the film cooling efficiency of the V-shaped film hole structure with a U-shaped structure having an opening and closing angle of 90° and a U-shaped structure having an opening and closing angle of 120° according to the present invention, wherein (a) is θ=90° and (b) is θ=120°.
[0021] In the figure, 1. The air film hole body, 2. The anti-kidney vortex pair, 3. The kidney vortex pair. DETAILED DESCRIPTION
[0022] The following describes in detail embodiments of the present application, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.
[0023] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.
[0024] Specific embodiment 1 of the V-shaped air film hole structure of the present invention: In this embodiment, Figure 1 、 Figure 2 、 Figure 3 and Figure 4As shown, the V-shaped air film hole structure comprises: an air film hole body 1, the air film hole body 1 comprises a symmetrically arranged left arm and a right arm, the left arm and the right arm are connected by an arc segment, wherein the inner area wrapped by the left arm, the right arm and the arc segment is the inner side of the air film hole, the outer area opposite thereto is the outer side of the air film hole, and the outer side of the air film hole is a V-shaped structure; when the cold air flows out from the side position of the inner side of the air film hole, a pair of inverted kidney-shaped vortices is formed, and when the cold air flows out from the side position of the outer side of the air film hole, a pair of kidney-shaped vortices is formed, that is, under the mainstream gas, when the cold air flows out from the side position of the inner side of the air film hole, an inverted kidney-shaped vortex pair 2 is formed, and when the cold air flows out from the side position of the outer side of the air film hole, a kidney-shaped vortex pair 3 is formed.
[0025] The V-shaped angle formed by the intersection of the outer side surfaces of the left and right arms is the opening and closing angle, and the opening and closing angle is between 90° and 120°. The extended ends of the left and right arms are provided with left and right arm end curved surfaces, respectively. The inner side surface of the left arm is connected to one end of the outer side surface of the left arm via the left arm end curved surface, and the inner side surface of the right arm is connected to one end of the outer side surface of the right arm via the right arm end curved surface. The angle α between the outer side surfaces of the left and right arms and the horizontal plane is 30°.
[0026] Specific embodiment 2 of the V-shaped air film hole structure of the present invention: Based on the technical concept of the present invention described above, or based on the specific embodiment of the present invention described above, another embodiment is provided below.
[0027] In this embodiment, Figure 1 、 Figure 2 and Figure 3 As shown in the figure, the inner side of the left arm is arranged parallel to the outer side of the left arm, and the inner side of the right arm is arranged parallel to the outer side of the right arm, so that the inner side of the film hole has a V-shaped structure. The existence of the compound angle can affect the relative strength of the kidney-shaped vortex to the three branches, prompting the formation of a flow field dominated by a certain branch downstream. Utilizing the influence of the compound angle, a film hole with a V-shaped structure on the inner side of the film hole is constructed, so that when the cold air flows out from the side position of the V-shaped structure, a pair of anti-kidney-shaped vortices are formed. When the cold air flows out from the side position of the outer side of the film hole, it is pressed against the wall, suppressing the cold air from rising, thereby improving the film cooling efficiency.
[0028] Specifically, in this embodiment, the opening and closing angle θ1 is 90°. The spacing between the inner side of the left arm and the outer side of the left arm, as well as the spacing between the inner side of the right arm and the outer side of the right arm, is equal to H1. Along the extension direction of the left and right arms, the length L1 of the left and right arms is 4 H1. The radius R1 of the outer curved surface of the arc segment, the radius R2 of the inner curved surface, and the radius R3 of the left and right arm end curved surfaces are all equal to H1. That is, the radius R1 of the outer curved surface of the arc segment is H1, the radius R2 of the inner curved surface is H1, and the radius R3 of the left and right arm end curved surfaces is H1.
[0029] The above structure Figure 4 The inner side of the V-shaped air film hole is a V-shaped structure. From the vorticity cloud diagram (a) of the downstream flow field distribution of the V-shaped air film hole structure (X=3D), it can be concluded that the anti-kidney vortex pair 2 formed by the cold air flowing out of the inner side of the left and right arms of the V-shaped air film hole structure can effectively suppress the kidney vortex pair 3 formed by the cold air flowing out of the outer side of the left and right arms of the hole to the wall, reducing the lifting of the cold air from the wall ( Figure 4 (b) Temperature cloud diagram), improves the adhesion of cold air and increases the film cooling efficiency. The V-shaped film hole structure with a V-shaped inner side of the film hole in this embodiment is compared with the span-averaged film cooling efficiency of the circular hole in the prior art, as shown in FIG. Figure 5 and Figure 6 As shown, Figure 5 It can be concluded that the cooling efficiency of the V-shaped air film hole structure with the inner side of the air film hole being a V-shaped structure is much higher than the air film cooling efficiency of the circular hole. The design of the V-shaped air film hole structure with the inner side of the air film hole being a V-shaped structure can achieve a higher cooling effect. Figure 6 As Figure 5 In addition, the two-dimensional distribution of the film cooling efficiency of the V-shaped film hole structure with a V-shaped structure on the inner side of the film hole and the circular hole on the wall is demonstrated. The effective air film width and strength formed after the cold air flows out of the V-shaped film hole structure with a V-shaped structure on the inner side of the film hole are much higher than those of the circular hole.
[0030] Specific embodiment 3 of the V-shaped air film hole structure of the present invention: Based on the technical concept of the present invention described above, or based on the specific embodiment of the present invention described above, another embodiment is provided below.
[0031] In this embodiment, Figure 7 、 Figure 8 、 Figure 11 and Figure 12As shown, the outer side surface of the left arm and the outer side surface of the right arm are symmetrically arranged, and the inner side surface of the left arm and the inner side surface of the right arm are parallelly arranged, so that the inner side of the air film hole is a U-shaped structure, which can strengthen the strength of the anti-kidney vortex pair 2, expand its influence area, and improve the adhesion of the cold air. Specifically, the arc-shaped surface at the end of the left arm includes an outer fillet and an inner fillet, and the outer fillet and the inner fillet are connected by a connecting plane. The outer side surface of the left arm is connected to the outer fillet, and the inner side surface of the left arm is connected to the inner fillet; the distance between the outer side surface of the left arm and the plane parallel to it and passing through the center position of the inner arc surface of the arc segment is H2, the radius R1 of the outer arc surface of the arc segment is equal to the distance H2, the radius R2 of the inner arc surface of the arc segment is 0.73 H2-1.2 H2, and the radius R3 of the outer fillet is ， The radius R4 of the inner fillet is 0.53H2, and the radius R4 of the inner fillet is 0.67H2. In a direction parallel to the outer side surface of the left arm, the intersection line of the plane passing through the center of the circle where the outer curved surface of the arc segment is located and the connecting plane is the first intersection line. The distance L2 between the center line of the circle where the outer curved surface of the outer arc segment is located and the first intersection line is 4.7H2-6H2. In a direction perpendicular to the connecting plane, the intersection line of the plane passing through the center of the circle where the outer curved surface of the outer arc segment is located and the connecting plane is the second intersection line. The distance F1 between the first and second intersection lines is 4H2-4.2H2.
[0032] like Figure 7 、 Figure 8 As shown, when the opening and closing angle θ2 is 90°, the distance L2 between the center line of the outer arc surface of the outer arc segment and the first intersection line is 6H2; the radius R1 of the outer arc surface of the arc segment is equal to the spacing H2, that is, R1=H2, the radius R2 of the inner arc surface of the arc segment is 0.73H2, and the radius R3 of the outer rounded corner is 0.73H2. ， The radius R4 of the inner rounded corner is 0.67 H2; the distance F1 between the first intersection line and the second intersection line is 4.2 H2; in the direction perpendicular to the connecting plane, the distance F2 between the plane passing through the center position of the circle where the outer arc surface of the outer arc segment is located and the plane passing through the center position of the circle where the inner rounded corner is located is 2.1 H2.
[0033] The spanwise average film cooling efficiency of the V-shaped film hole structure with a U-shaped inner side corresponding to the film hole with an opening and closing angle of 90° is compared with that of the V-shaped film hole structure with a V-shaped inner side. Figure 9 and Figure 10As shown, it can be concluded that: at low blowing ratio, the cooling effect of the V-shaped air film hole structure with a U-shaped structure on the inner side of the air film hole is similar to that of the V-shaped air film hole structure with a V-shaped structure on the inner side of the air film hole. As the blowing ratio gradually increases, the V-shaped air film hole structure with a U-shaped structure on the inner side of the air film hole shows a better cooling effect.
[0034] like Figure 11 、 Figure 12 As shown, when the opening and closing angle θ3 is 120°, the distance L2 between the center line of the outer arc surface of the outer arc segment and the first intersection line is 4.7H2; the radius R1 of the outer arc surface of the arc segment is equal to the spacing H2, that is, R1=H2, the radius R2 of the inner arc surface of the arc segment is 1.2H2, and the radius R3 of the outer rounded corner is ， The radius R4 of the inner fillet is 0.67 H2; the distance F1 between the first intersection line and the second intersection line is 4 H2; in the direction perpendicular to the connecting plane, the distance F2 between the plane passing through the center of the circle where the outer arc surface of the outer arc segment is located and the inner side surface of the left arm ， is 1.2 H2.
[0035] The spanwise average film cooling efficiency of the V-shaped film hole structure with a U-shaped inner side corresponding to the film hole with an opening and closing angle of 90° is compared with that of the V-shaped film hole structure with a U-shaped inner side corresponding to the film hole with an opening and closing angle of 120°. Figure 13 and Figure 14 As shown in the figure, it can be concluded that: at low blowing ratios, the cooling effects of the V-shaped film hole structure with a U-shaped inner side corresponding to an opening and closing angle of 90° and the V-shaped film hole structure with a U-shaped inner side corresponding to an opening and closing angle of 120° are similar. However, as the blowing ratio gradually increases, the V-shaped film hole structure with a U-shaped inner side corresponding to an opening and closing angle of 120° exhibits better cooling effect. When the blowing ratio is greater than 1, the V-shaped film hole structure with a U-shaped inner side corresponding to an opening and closing angle of 120° exhibits even better film cooling effect.
[0036] The present invention also provides a turbine blade comprising the above-mentioned V-shaped air film hole structure.
[0037] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. The scope of patent protection of the present invention shall be based on the claims. Any equivalent structural changes made using the contents of the description and drawings of the present invention shall be included in the scope of protection of the present invention.
Claims
1. A V-shaped air film hole structure, characterized in that: include: The air film hole body comprises a symmetrically arranged left arm and a right arm, and the left arm and the right arm are connected by an arc segment, wherein the inner area wrapped by the left arm, the right arm and the arc segment is the inner side of the air film hole, and the outer area opposite thereto is the outer side of the air film hole, and the outer side of the air film hole is a V-shaped structure; when the cold air flows out from the side position of the inner side of the air film hole, a pair of inverted kidney-shaped vortices are formed, and when the cold air flows out from the side position of the outer side of the air film hole, a pair of kidney-shaped vortices are formed.
2. The V-shaped air film hole structure according to claim 1, characterized in that: The V-shaped angle formed by the intersection of the outer side surface of the left arm and the outer side surface of the right arm is an opening and closing angle, and the opening and closing angle is 90°-120°.
3. The V-shaped air film hole structure according to claim 2, characterized in that: The end positions of the extended ends of the left arm and the right arm are provided with a left arm end arc surface and a right arm end arc surface, so that the inner side surface of the left arm and one end of the outer side surface of the left arm are connected through the left arm end arc surface, and the inner side surface of the right arm and one end of the outer side surface of the right arm are connected through the right arm end arc surface.
4. The V-shaped air film hole structure according to claim 3, characterized in that: The inner side surface of the left arm is parallel to the outer side surface of the left arm, and the inner side surface of the right arm is parallel to the outer side surface of the right arm, so that the inner side of the air film hole is a V-shaped structure.
5. The V-shaped air film hole structure according to claim 4, characterized in that: The distance between the inner side surface of the left arm and the outer side surface of the left arm, and the distance between the inner side surface of the right arm and the outer side surface of the right arm are equal to the distance H1. Along the extension direction of the left arm and the right arm, the length L1 of the left arm and the right arm is 4 H1, and the radius R1 of the outer curved surface of the arc segment, the radius R2 of the inner curved surface, and the radius R3 of the curved surface at the end of the left arm and the curved surface at the end of the right arm are all equal to the distance H1.
6. The V-shaped air film hole structure according to claim 3, characterized in that: The outer side surface of the left arm and the outer side surface of the right arm are symmetrically arranged, and the inner side surface of the left arm and the inner side surface of the right arm are parallelly arranged, so that the inner side of the air film hole is a U-shaped structure.
7. The V-shaped air film hole structure according to claim 6, wherein: The arc-shaped surface at the end of the left arm includes an outer rounded corner and an inner rounded corner, and the outer rounded corner and the inner rounded corner are connected by a connecting plane. The outer side surface of the left arm is connected to the outer rounded corner, and the inner side surface of the left arm is connected to the inner rounded corner. The distance between the outer side surface of the left arm and the plane parallel to it and passing through the center position of the inner arc surface of the arc segment is H2. The radius R1 of the outer arc surface of the arc segment is equal to the distance H2. The radius R2 of the inner arc surface of the arc segment is 0.73 H2-1.2 H2. The radius R3 of the outer rounded corner is ， The radius R4 of the inner fillet is 0.67 H2.
8. The V-shaped air film hole structure according to claim 7, wherein: In a direction parallel to the outer side surface of the left arm, the intersection line of the plane passing through the center position of the circle where the outer curved surface of the arc segment is located and the connecting plane is the first intersection line, and the distance L2 between the center line of the circle where the outer curved surface of the outer curved segment is located and the first intersection line is 4.7 H2-6 H2; in a direction perpendicular to the connecting plane, the intersection line of the plane passing through the center position of the circle where the outer curved surface of the outer curved segment is located and the connecting plane is the second intersection line, and the distance F1 between the first intersection line and the second intersection line is 4 H2-4.2 H2.
9. The V-shaped air film hole structure according to claim 8, wherein: When the opening and closing angle is 90°, the distance F2 between the plane passing through the center of the circle where the outer arc surface of the outer arc segment is located and the plane passing through the center of the circle where the inner rounded corner is located in the direction perpendicular to the connecting plane is 2.1 H2; when the opening and closing angle is 120°, the distance F2 between the plane passing through the center of the circle where the outer arc surface of the outer arc segment is located and the inner side surface of the left arm in the direction perpendicular to the connecting plane is ， is 1.2 H2.
10. A turbine blade, characterized in that: It comprises the V-shaped air film hole structure described in any one of claims 1-9.