Double-wall cooling structure and turbine blade

Abstract

The invention provides a double-wall cooling structure. The double-wall cooling structure comprises an air film hole plate, an impingement hole plate and a plurality of narrow walls, a plurality of air film holes are formed in the air film hole plate, a plurality of impact holes are formed in the impact hole plate, and the impact hole plate and the air film hole plate are arranged at intervals to form a cooling channel; the narrow walls are arranged in the cooling channel at intervals in the first direction parallel to the flow direction of gas outside the gas film hole plate, the cooling channel is divided into a plurality of cold air cavities, and the gas film hole communicates with the impact hole through the cold air cavities; wherein in the orthographic projection in the thickness direction of the gas film pore plate, the projections of the gas inlet ends of the gas film pores and the projections of the gas outlet ends of the impact pores are arranged in a staggered manner.

Description

Technical Field

[0001] The present disclosure relates to the technical field of turbine blade cooling of a gas turbine, and more specifically, to a double-wall cooling structure and a turbine blade. Background Art

[0002] The core components of a gas turbine include a compressor, a combustion chamber, and a turbine. The high-pressure air compressed by the compressor is mixed with the fuel and burned in the combustion chamber. The high-temperature and high-pressure gas generated then enters the turbine for energy conversion. In this process, the turbine blades and other components face extremely high temperature challenges.

[0003] In order to improve the efficiency and power density of the engine, increasing the temperature before the turbine is the key. However, this also puts higher requirements on the high temperature resistance of the turbine blades. For this reason, cooling technology has become an important means to extend the life of turbine blades and ensure the safe operation of turbines. In recent years, double-wall cooling technology, as an advanced micro-scale cooling technology, has reduced the size of heat exchange from the blade level (0.5-1.5cm) to the cold air cavity level (0.5-1.5mm), thereby improving the heat transfer coefficient and heat transfer area.

[0004] The double-wall cooling system combines multiple methods such as impingement cooling, column rib turbulence and external film cooling. Its internal flow is complex, involving multiple factors such as impingement jet, wall shear, turbulence column turbulence and film hole outflow. Under real working conditions, especially when there is an external pressure gradient, the double-wall cooling system may be affected by the migration of cold air, resulting in uneven distribution of film hole flow, which will have a serious impact on the cooling effect of the blade. Therefore, optimizing the work of this system is the key to improving blade cooling efficiency and ensuring engine performance. Summary of the invention

[0005] In view of this, the present disclosure provides a double-wall cooling structure, in which a plurality of narrow walls are arranged at intervals to divide the cooling channel between the film hole plate and the impact hole plate into a plurality of cold air cavities, and the film holes are ventilated separately to control the flow of the film holes.

[0006] One aspect of the present disclosure provides a double-wall cooling structure, including an air film orifice plate, an impact orifice plate and a plurality of narrow walls. The air film orifice plate is formed with a plurality of air film holes, the impact orifice plate is formed with a plurality of impact holes, the impact orifice plate and the air film orifice plate are arranged at intervals to form a cooling channel; the plurality of narrow walls are arranged at intervals in the cooling channel in a first direction parallel to the gas flow direction outside the air film orifice plate, and the cooling channel is divided into a plurality of cold air cavities, the air film holes and the impact holes are connected through the cold air cavities; wherein, in the orthographic projection in the thickness direction of the air film orifice plate, the projections of the air inlet end of the air film hole and the air outlet end of the impact hole are arranged in a staggered manner.

[0007] According to an embodiment of the present disclosure, it also includes a plurality of spoiler ribs, which are arranged on the surface of the above-mentioned air film orifice plate facing the above-mentioned impact orifice plate; in the orthographic projection of the above-mentioned air film orifice plate in the thickness direction, the projection of the above-mentioned spoiler ribs is located between the projections of the air inlet end of the above-mentioned air film hole and the air outlet end of the above-mentioned impact hole adjacent to each other in the second direction; wherein the above-mentioned second direction is orthogonal to the above-mentioned first direction.

[0008] According to an embodiment of the present disclosure, an angle between an extension direction of the spoiler rib and an extension direction of the narrow wall is 30 degrees to 150 degrees.

[0009] According to an embodiment of the present disclosure, the plurality of air film holes and the plurality of impact holes are configured to be arranged in a column array in the first direction and a row array in the second direction.

[0010] According to an embodiment of the present disclosure, the air film holes in adjacent column arrays are staggered in the second direction, and the impact holes in adjacent column arrays are staggered in the second direction.

[0011] According to an embodiment of the present disclosure, in the orthographic projection of the film hole plate in the thickness direction, the projections of the air inlet ends of the film holes and the air outlet ends of the impact holes are evenly spaced and distributed in the second direction.

[0012] According to an embodiment of the present disclosure, at least one row of the air film holes and at least one row of the impact holes are connected through one of the cold air cavities.

[0013] According to an embodiment of the present disclosure, the diameter of each of the air film holes is D, and the thickness of each of the narrow walls is 0.5D~2.5D.

[0014] According to an embodiment of the present disclosure, an extending direction of each of the air film holes extends in a direction inclined to a thickness direction of the air film hole plate.

[0015] Another aspect of the present disclosure provides a turbine blade, wherein the side wall of the turbine blade at least partially adopts the above-mentioned double-wall cooling structure.

[0016] According to an embodiment of the present disclosure, a double-wall cooling structure is provided, including an air film orifice plate, an impact orifice plate and a plurality of narrow walls arranged at intervals, wherein the narrow walls are arranged at intervals in the cooling channel parallel to the gas flow direction outside the air film orifice plate to form a plurality of cold air cavities, so that the air film holes and the impact holes are connected through the cold air cavities, and in the orthographic projection in the thickness direction of the air film orifice plate, the air inlet ends of the air film holes and the air outlet ends of the impact holes are arranged alternately, thereby not only achieving precise control of the air film hole flow rate, ensuring uniform distribution of the cooling airflow, and improving the cooling efficiency and effect, but also enhancing the stability of the cooling structure and the mixing effect of the gas flow, optimizing the overall cooling performance and extending the service life of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and other objects, features and advantages of the present disclosure will become more apparent through the following description of the embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0018] Figure 1 is a schematic diagram of a double-wall cooling structure according to an embodiment of the present disclosure.

[0019] Figure 2 is a three-dimensional cross-sectional view of a double-wall cooling structure according to an embodiment of the present disclosure.

[0020] Figure 3 is a schematic diagram of a double-wall cooling structure according to another embodiment of the present disclosure.

[0021] Figure 4 is a three-dimensional cross-sectional view of a double-wall cooling structure according to another embodiment of the present disclosure.

[0022] Figure 5 yes Figure 4 A three-dimensional view of the inner surface of the air film hole plate of the double-wall cooling structure is shown.

[0023] Figure 6 It is a schematic diagram of the arrangement of air film holes and impact holes according to an embodiment of the present disclosure.

[0024] Figure 7 It is a schematic diagram of the arrangement of air film holes and impact holes according to another embodiment of the present disclosure.

[0025] Figure 8 It is a cloud diagram of the Nusselt number distribution on the impact target surface of the double-wall cooling structure according to an embodiment of the present disclosure.

[0026] Fig. 9 It is a cloud diagram of the comprehensive cooling efficiency of the air film orifice plate of the double-wall cooling structure according to the embodiment of the present disclosure.

[0027] Fig.10 It is a flow distribution result diagram of each exhaust film hole of the double-wall cooling structure according to an embodiment of the present disclosure.

[0028] In the drawings, the meanings of the reference numerals are as follows:

[0029] 1. Air film orifice plate;

[0030] 11. Air film hole;

[0031] 111, air intake end;

[0032] 112, outlet end;

[0033] 2. Impact orifice plate;

[0034] 21. Impact hole

[0035] 3. Cooling channel;

[0036] 31. Air conditioning cavity;

[0037] 4. Narrow wall;

[0038] 5. Spoiler ribs;

[0039] α, a first angle; and

[0040] β, the second angle. DETAILED DESCRIPTION

[0041] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present disclosure. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present disclosure. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0042] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "include", "comprising", etc. used herein indicate the existence of the features, steps, operations and / or mechanisms, but do not exclude the existence or addition of one or more other features, steps, operations or mechanisms.

[0043] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0044] When using expressions such as "at least one of A, B, and C, etc.", they should generally be interpreted according to the meaning of the expression commonly understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0045] Figure 1 is a schematic diagram of a double-wall cooling structure according to an embodiment of the present disclosure. Figure 2 is a three-dimensional cross-sectional view of a double-wall cooling structure according to an embodiment of the present disclosure.

[0046] The embodiment of the present disclosure provides a blade, such as Figure 1 and Figure 2As shown, it includes an air film orifice plate 1, on which a plurality of air film holes 11 are formed; an impact orifice plate 2, on which a plurality of impact holes 21 are formed, and the impact orifice plate 2 and the air film orifice plate 1 are spaced apart to form a cooling channel 3; and a plurality of narrow walls 4, which are spaced apart in the cooling channel 3 in a first direction to divide the cooling channel 3 into a plurality of cold air cavities 31, and the first direction is parallel to the gas flow direction outside the air film orifice plate 1, and the air film holes 11 and the impact holes 21 are connected through the cold air cavities 31; wherein, in the orthographic projection in the thickness direction of the air film orifice plate 1, the projections of the air inlet end 111 of the air film hole 11 and the air outlet end of the impact hole 21 are staggered.

[0047] According to the above-mentioned setting method, a plurality of narrow walls 4 are arranged in the cooling channel 3 between the air film hole plate 1 and the impact hole plate 2 to form a plurality of cold air cavities 31, thereby achieving effective connection between the air film holes and the impact holes. The cold air cavities 31 are used to supply air to the connected air film holes 11 separately, thereby ensuring uniform distribution of the cooling airflow.

[0048] In detail, the air inlet end 111 of the air film hole 11 and the air outlet end of the impact hole 21 are arranged alternately in the orthographic projection, and the cold air impacts the inner surface of the external air film orifice plate 1 through the impact hole 21 and enhances the heat exchange. In addition, the impact jet formed by the cold air further exchanges heat with the narrow wall 4, and finally flows out through the air film hole 11, forming a cold air cover on the outer surface of the air film orifice plate 1 to isolate the external high-temperature mainstream.

[0049] It should also be noted that the air inlet end 111 of the air film hole 11 and the air outlet end of the impact hole 21 are not provided with a narrow wall 4 .

[0050] In an illustrative embodiment, the diameter of each air film hole 11 is D, and the thickness of each narrow wall 4 is 0.5D to 2.5D.

[0051] In detail, the thinner the narrow wall 4 is, the better the heat exchange effect is, but the thickness of the narrow wall 4 is related to the strength. Therefore, under the premise of ensuring the strength of the double-wall cooling structure, the thickness of the narrow wall 4 can be appropriately reduced.

[0052] In an illustrative embodiment, the thickness of the air film orifice plate 1 is 1D to 2.5D.

[0053] In an illustrative embodiment, the thickness of the impact orifice plate 2 is 0.5D to 1.5D.

[0054] In an illustrative embodiment, the height of the cooling channel 3 (ie, the distance between the film orifice plate 1 and the impact orifice plate 2 ) is 0.5D to 2.5D.

[0055] In an exemplary embodiment, the diameter of the impact hole 21 is 0.5D-2D.

[0056] In an illustrative embodiment, Figure 1 As shown, the impact hole 21 extends in the thickness direction of the impact hole plate 2, and the second angle between the central axis of the impact hole 21 and the wall surface of the cooling channel 3 is β, and β is 90 degrees.

[0057] According to the above-mentioned setting method, since the central axis of the impact hole 21 is perpendicular to the wall of the cooling channel 3, the cooling gas can directly and vertically impact the air film orifice plate 1, thereby achieving an efficient direct impact cooling effect. At the same time, the 90-degree impact angle helps to maximize the conversion of the kinetic energy of the cooling gas into heat exchange efficiency, thereby improving the overall cooling efficiency.

[0058] In an illustrative embodiment, Figure 1 As shown, the extension direction of each air film hole 11 extends in a direction inclined to the thickness direction of the air film hole plate 1 .

[0059] In detail, the included angle between the central axis of the air film hole 11 and the extending direction of the outer surface of the air film hole plate 1 is α, and α is 20 degrees to 90 degrees.

[0060] According to the above arrangement, the inclined film holes 11 design helps to improve the distribution of cooling gas on the surface of the film plate 1, thereby improving the cooling efficiency. The inclined film holes 11 help to form a more uniform air film coverage on the surface of the film plate 1, reducing local overheating.

[0061] In an illustrative embodiment, in the orthographic projection of the air film hole plate 1 in the thickness direction, the line connecting the midpoints of the projections of the air inlet end 111 and the air outlet end 112 of the air film hole 11 is parallel to the first direction, that is, inclined along the direction of external gas flow.

[0062] According to the above-mentioned arrangement, since the inclination direction of the air film hole is consistent with the flow direction of the external gas, the injection of cooling gas can more effectively cover the surface of the air film hole plate 1, thereby enhancing the cooling effect.

[0063] Figure 3 is a schematic diagram of a double-wall cooling structure according to another embodiment of the present disclosure. Figure 4 is a three-dimensional cross-sectional view of a double-wall cooling structure according to another embodiment of the present disclosure. Figure 5 yes Figure 4 A three-dimensional view of the inner surface of the air film hole plate of the double-wall cooling structure is shown.

[0064] In an illustrative embodiment, Figures 3 to 5 As shown, it also includes a plurality of spoiler ribs 5, which are arranged on the surface of the air film orifice plate 1 facing the impact orifice plate 2; in the orthographic projection of the air film orifice plate 1 in the thickness direction, the projection of the spoiler ribs 5 is located between the projections of the air inlet end 111 of the air film hole 11 and the air outlet end of the impact hole 21 adjacent to each other in the second direction; wherein the second direction is orthogonal to the first direction.

[0065] The surface of the air film orifice plate 1 facing the impact orifice plate 2 is the inner surface of the air film orifice plate 1, i.e., the impact target surface. The impact target surface refers to the impact effect on a solid surface when a fluid (such as gas or liquid) hits the solid surface in the form of a high-speed jet. The impact target surface usually has to withstand high pressure, high temperature and possible chemical corrosion, so special materials and designs are required to ensure the strength and durability of the structure.

[0066] According to the above-mentioned arrangement, spoiler ribs 5 are arranged on the impact target surface (inner surface of the air film orifice plate 1) of the double-wall cooling structure, and these spoiler ribs 5 are located in the cooling gas flow path, between the impact hole 21 and the air film hole 11. Such a layout effectively causes disturbance of the air flow, thereby significantly improving the heat exchange efficiency between the cooling gas and the air film orifice plate 1, and further significantly reducing the working temperature of the air film orifice plate 1.

[0067] In an illustrative embodiment, the narrow wall 4 is configured to extend in the second direction, so that the cold air cavity 31 separated by two adjacent narrow walls 4 also extends in the second direction.

[0068] According to the above-mentioned setting method, the cold air cavities extending in the second direction are distributed at intervals in the first direction, and the first direction is parallel to the external gas flow direction, thereby overcoming the cold air migration caused by the pressure gradient of the external gas of the air film orifice plate 1 under actual working conditions. The cold air cavity 31 supplies air to the air film hole 11 separately, ensuring uniform flow distribution of each air film hole 11.

[0069] In an illustrative embodiment, the height of the spoiler rib 5 is 0.1D-0.5D.

[0070] In an illustrative embodiment, the angle between the extension direction of the spoiler rib 5 and the extension direction of the narrow wall 4 is 30 degrees to 150 degrees.

[0071] According to the above-mentioned setting mode, the specific angle helps to guide the cooling gas to flow more effectively on the inner surface of the air film orifice plate 1, reducing the airflow dead zone and improving the cooling efficiency. By optimizing the direction of the spoiler ribs, the pressure loss in the gas flow can be reduced and the overall performance of the cooling system can be improved.

[0072] Figure 6 It is a schematic diagram of the arrangement of air film holes and impact holes according to an embodiment of the present disclosure.

[0073] In an illustrative embodiment, Figure 6 As shown, the plurality of air film holes 11 and the plurality of impact holes 21 are configured to be arranged in a column array in a first direction and a row array in a second direction.

[0074] According to the above-mentioned setting mode, through the arrangement of column array and row array, the cooling gas can be more evenly distributed to the entire surface of the air film orifice plate 1, reducing the cooling dead corners and improving the overall cooling efficiency. The orderly arrangement of the air film holes 11 and the impact holes 21 enhances the heat exchange between the cooling gas and the air film orifice plate 1, which helps to remove heat more quickly, and can effectively avoid local overheating, thereby extending the service life of the air film orifice plate 1.

[0075] In an illustrative embodiment, Figure 6 As shown, in the orthographic projection of the air film hole plate 1 in the thickness direction, the projections of the air inlet end 111 of the air film hole 11 and the air outlet end of the impact hole 21 are evenly spaced and distributed in the second direction.

[0076] According to the above-mentioned setting method, the air inlet end 111 of the air film hole 11 and the air outlet end of the impact hole 21 uniformly distributed in the second direction match the extension direction of the cold air cavity 31, which helps to form a stable airflow pattern inside each cold air cavity 31, avoids airflow short-circuiting and uneven cooling, ensures that the cooling gas is more evenly distributed on the air film hole plate 1, improves the cooling efficiency, and improves the thermal stress distribution on the air film hole plate 1, thereby reducing material fatigue and damage caused by uneven thermal stress.

[0077] Figure 7 It is a schematic diagram of the arrangement of air film holes and impact holes according to another embodiment of the present disclosure.

[0078] In an alternative exemplary embodiment, as Figure 7 As shown, the air film holes 11 of adjacent arrays are staggered in the second direction, and the impact holes 21 of adjacent arrays are staggered in the second direction.

[0079] According to the above-mentioned setting method, the staggered setting method of each column of air film holes 11 and each column of impact holes 21 makes the air film holes 11 and the impact holes 21 also present an interval distribution in the first direction, which can further optimize the distribution of cooling airflow and reduce local overheating, thereby improving the cooling efficiency, making the distribution of hot and cold areas of the air film hole plate 1 more even, and reducing the negative impact of uneven thermal stress distribution.

[0080] In an illustrative embodiment, at least one exhaust film hole 11 and at least one row of impact holes are connected through a cold air cavity 31 .

[0081] According to the above-mentioned arrangement, each cold air cavity 31 can be used to connect multiple exhaust film holes 11 and multiple rows of impact holes 21, thereby increasing the adaptability of the double-wall cooling structure.

[0082] Another aspect of an embodiment of the present disclosure provides a turbine blade, wherein at least a portion of a side wall of the turbine blade adopts the above-mentioned double-wall cooling structure.

[0083] According to the embodiments of the present disclosure, the thickness of the film orifice plate 1, the height of the cooling channel 3, and the thickness of the impact orifice plate 2 can be adjusted accordingly according to the heat load on the gas side and the structural strength, and the arrangement and density of the film holes 11 and the impact holes 21, the diameter of the impact holes 21, the height of the spoiler ribs 5 and the thickness of the narrow wall 4 are also adjusted according to the heat load on the gas side.

[0084] Figure 8 It is a cloud diagram of the Nusselt number distribution on the impact target surface of the double-wall cooling structure according to an embodiment of the present disclosure.

[0085] According to the embodiments of the present disclosure, Figure 8 As shown, the Nusselt number distribution of the impact target surface of the double-wall cooling structure and the combined structure of the cold air cavity 31 separated by the spoiler ribs 5 and the narrow wall 4 make the heat exchange distribution on the target surface arranged regularly.

[0086] The Nusselt number (Nu) is a dimensionless number that represents the intensity of convective heat transfer. It is an indicator of the characteristics of fluid flow and thermal boundary layers. In the turbine blade cooling technology of gas turbine engines, the distribution of the Nusselt number can provide important information about the heat transfer effect on the blade surface. In the double-wall cooling system, the Nusselt number is higher in the impingement cooling area because the cooling gas directly impinges on the inner wall of the blade, so the heat transfer effect here is better.

[0087] Fig. 9 It is a cloud diagram of the comprehensive cooling efficiency of the air film orifice plate of the double-wall cooling structure according to the embodiment of the present disclosure.

[0088] According to the embodiments of the present disclosure, Fig. 9 As shown, the cooling efficiency around the air outlet 112 of the air film hole 11 is evenly distributed, indicating that the cooling airflow ejected from the air film hole 11 of the double-wall cooling structure disclosed in the present invention is evenly distributed.

[0089] Fig.10 It is a flow distribution result diagram of each exhaust film hole of the double-wall cooling structure according to an embodiment of the present disclosure.

[0090] According to the embodiments of the present disclosure, Fig.10 As shown, compared with the existing impact divergent double-wall, the flow distribution of the air film holes 11 in different hole rows of the double-wall cooling structure of the present application is closer, indicating that the cold air migration phenomenon, that is, the problem of uneven flow distribution of the air film holes 11, is effectively improved.

[0091] It will be appreciated by those skilled in the art that the features described in the various embodiments of the present disclosure may be combined and / or combined in a variety of ways, even if such combinations or combinations are not explicitly described in the present disclosure. In particular, without departing from the spirit and teachings of the present disclosure, the features described in the various embodiments of the present disclosure may be combined and / or combined in a variety of ways. All of these combinations and / or combinations fall within the scope of the present disclosure.

[0092] The embodiments of the present disclosure are described above. However, these embodiments are only for illustrative purposes and are not intended to limit the scope of the present disclosure. Although the embodiments are described above, this does not mean that the measures in the various embodiments cannot be used in combination to advantage. Without departing from the scope of the present disclosure, those skilled in the art may make a variety of substitutions and modifications, which should all fall within the scope of the present disclosure.

Claims

1. A double-wall cooling structure, characterized in that: include: An air film orifice plate (1), wherein a plurality of air film holes (11) are formed on the air film orifice plate (1); An impact orifice plate (2), wherein a plurality of impact holes (21) are formed on the impact orifice plate (2), and the impact orifice plate (2) and the air film orifice plate (1) are arranged at intervals to form a cooling channel (3); and A plurality of narrow walls (4) are arranged in the cooling channel (3) at intervals in a first direction parallel to the gas flow direction outside the air film hole plate (1), so as to divide the cooling channel (3) into a plurality of cold air cavities (31), and the air film holes (11) and the impact holes (21) are connected via the cold air cavities (31); Wherein, in the orthographic projection of the air film hole plate (1) in the thickness direction, the projections of the air inlet ends (111) of the air film holes (11) and the air outlet ends of the impact holes (21) are arranged in a staggered manner.

2. The double-wall cooling structure according to claim 1, characterized in that: It also comprises a plurality of spoiler ribs (5) arranged on a surface of the air film orifice plate (1) facing the impact orifice plate (2); In an orthographic projection of the air film hole plate (1) in the thickness direction, the projection of the spoiler rib (5) is located between the projections of the air inlet end (111) of the air film hole (11) and the air outlet end of the impact hole (21) adjacent to each other in the second direction; The second direction is orthogonal to the first direction.

3. The double-wall cooling structure according to claim 2, characterized in that: The included angle between the extension direction of the spoiler rib (5) and the extension direction of the narrow wall (4) is 30 degrees to 150 degrees.

4. The double-wall cooling structure according to claim 2, characterized in that: The plurality of air film holes (11) and the plurality of impact holes (21) are both configured to be arranged in the form of a column array in the first direction and a row array in the second direction.

5. The double-wall cooling structure according to claim 4, characterized in that: The air film holes (11) of adjacent column arrays are staggered in the second direction, and the impact holes (21) of adjacent column arrays are staggered in the second direction.

6. The double-wall cooling structure according to claim 4 or 5, characterized in that: In the orthographic projection of the air film hole plate (1) in the thickness direction, the projections of the air inlet end (111) of the air film hole (11) and the air outlet end of the impact hole (21) are evenly spaced and distributed in the second direction.

7. The double-wall cooling structure according to claim 6, characterized in that: At least one row of the air film holes (11) and at least one row of the impact holes are connected via one cold air cavity (31).

8. The double-wall cooling structure according to claim 1, characterized in that: The diameter of each of the air film holes (11) is D, and the thickness of each of the narrow walls (4) is 0.5D-2.5D.

9. The double-wall cooling structure according to claim 1, characterized in that: The extension direction of each of the air film holes (11) extends in a direction inclined to the thickness direction of the air film hole plate (1).

10. A turbine blade, characterized in that: The side wall of the turbine blade at least partially adopts the double-wall cooling structure according to any one of claims 1 to 9.

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