Gas turbine blade

Abstract

The invention provides a gas turbine blade which comprises a blade wall, an inner cavity, a plurality of first gas film holes and at least one groove-shaped gas film hole, the inner cavity is located in the blade, the gas turbine blade further comprises a gas collecting cavity, and the first gas film holes, the groove-shaped gas film holes and the gas collecting cavity are all located in the blade wall. The air collecting cavity is in fluid communication with the inner cavity through the multiple first air film holes, and the air collecting cavity is in fluid communication with the exterior of the blade through at least one groove-shaped air film hole. The mode that the first air film holes of the hole-shaped structures are combined with the groove-shaped air hole films is adopted, and the cooling efficiency of the air film holes is improved while the strength of the blade is guaranteed.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of gas turbine technology, in particular, to a gas turbine blade. BACKGROUND

[0002] The inlet temperature of the gas turbine is very high, and the excessively high temperature has a great influence on the service life of the turbine blade and the mechanical properties of the material. In order to reduce the temperature of the blade, gas film holes are generally processed on the surface of the blade for cooling. The most commonly used hole type for discrete hole gas film cooling is cylindrical hole or profiled hole. This hole type has the advantages of simple structure, no influence on blade strength, easy to process, etc., and is widely used in gas turbine blades. However, with the gradual increase of the inlet temperature of the turbine, the disadvantages of discrete holes gradually appear, such as low cooling effect, small gas film coverage area, easy to blow off the wall under high blowing ratio, large mixing loss, etc. The use of slot-type gas film holes can effectively reduce the separation of gas film cooling gas and the wall, but since the long slot is processed along the wall, it is easy to cause the structural strength of the blade wall to be weakened, reducing the service life of the blade.

[0003] To solve the above technical problems, the prior art, such as CN119373558A, proposes a discrete gas film cooling structure combined with holes and slots and a turbine blade. The discrete gas film cooling structure comprises: a plurality of cold gas inlets, each cold gas inlet comprising at least two discrete distributed gas film holes, the diameter of the gas film hole being smaller than the diameter of the cross section of the standard cylindrical hole, and the gas film hole being used for passing in cold gas; each gas film hole is sequentially connected with a straight section cold gas channel and an expansion section cold gas channel; wherein, the expansion section cold gas channels corresponding to the adjacent gas film holes in each cold gas inlet are penetrated by a connecting structure plane at a predetermined distance from the outlet end, forming a slot type structure at the outlet end, and the expansion section cold gas channel and the slot type structure are used to expand the coverage width of the ejected cold gas. This technical solution can significantly expand the outlet gas film coverage width and form a multi-peak gas film form at the outlet, significantly improving the gas film cooling effect without increasing the amount of cold gas. For example, CN115045720A proposes a turbine blade leading edge gas film cooling structure, which comprises a blade leading edge and a plurality of gas film holes with an equivalent diameter D arranged on the blade leading edge. The plurality of gas film holes are slot-type holes, and the plurality of gas film holes comprise a plurality of circumferential gas film hole rows. Among the plurality of circumferential gas film hole rows, the circumferential gas film hole row closest to the stagnation line of the blade leading edge, the offset distance S between the center line of each gas film hole and the stagnation line of the blade leading edge, and the equivalent diameter D of the gas film hole satisfy the following numerical relationship: S = 0.5D - 1.0D.

[0004] However, the prior art solutions cannot completely solve the above technical problems. SUMMARY

[0005] The purpose of the present application is to solve the above technical problems.

[0006] To achieve the above object, the present application provides a gas turbine blade, comprising a blade wall, an internal chamber, a plurality of first film holes and at least one slot film hole, the internal chamber is located inside the blade, further comprising a collecting chamber, the first film holes, the slot film hole and the collecting chamber 4 are all located in the blade wall, the collecting chamber is in fluid communication with the internal chamber through a plurality of first film holes, and the collecting chamber is in fluid communication with the outside of the blade through at least one slot film hole.

[0007] Further, each of the plurality of first film holes is a hole structure with equal cross-sectional area.

[0008] Further, the distance between two adjacent first film holes is 1-1.5 times the maximum inner diameter of the first film hole.

[0009] Further, the flow area of the slot film hole is not greater than 1.2 times the total flow area of all the first film holes.

[0010] Further, from one end close to the internal chamber to one end close to the collecting chamber, the first film hole is inclined to the direction of gas flow in the gas turbine gas flow passage.

[0011] Further, from one end close to the collecting chamber to one end close to the outside of the blade, the slot film hole is inclined to the direction of gas flow in the gas turbine gas flow passage.

[0012] Further, it further comprises a collecting groove and a cover plate, the collecting groove is located on the outer side of the blade wall, the cover plate is located on the outer side of the blade wall, the cover plate covers part of the collecting groove, and the collecting chamber is located between the cover plate and the bottom surface of the collecting groove.

[0013] Further, the depth of the collecting groove is 10%-50% of the thickness of the corresponding blade wall.

[0014] Further, the bottom surface of the collecting groove and the inner side surface of the cover plate are both flat surfaces, the bottom surface of the collecting groove and the inner side surface of the cover plate are parallel, and the height of the collecting chamber along the normal direction of the bottom surface of the collecting groove is constant.

[0015] Further, the total cross-sectional area of the plurality of first film holes close to the end port of the collecting chamber is 30%-50% of the area of the bottom surface of the collecting groove.

[0016] Further, the slot film hole is located between the side wall of the collecting groove and the cover plate.

[0017] Further, the slot-shaped air film hole is located on the cover plate, and the slot-shaped air film hole penetrates the cover plate and fluidly communicates the outside of the blade and the gas collecting cavity.

[0018] The above technical solutions of the present application achieve at least the following technical effects: 1. In the present application, the gas collecting cavity is arranged in the blade wall, and the first air film hole and the slot-shaped air film hole are communicated through the gas collecting cavity, which improves the inlet air flow stability of the slot-shaped air film hole, the outlet flow is more stable, and the covering effect of the cold air is ensured.

[0019] 2. In the present application, the first air film hole with a hole structure is combined with the slot-shaped air film hole, which improves the cooling efficiency of the air film hole while ensuring the strength of the blade.

[0020] 3. In the present application, the spacing between the first air holes is small, the cooling is uniform, and the stress concentration problem caused by the large temperature difference of different parts of the blade is avoided.

[0021] 4. In the present application, the first air film hole and the slot-shaped air film hole can be machined respectively, avoiding the machining of special-shaped hole structures, and the shapes of the first air film hole and the slot-shaped air film hole are relatively simple, without machining precision problems, greatly reducing the machining difficulty.

[0022] Additional aspects and advantages of the present application will be partially given in the following description, partially will become obvious from the following description, or will be understood by the practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0023] The drawings accompanying the specification of the present application serve to provide a further understanding of the present application, the illustrative embodiments of the present application and their descriptions serve to explain the present application, and do not constitute an improper limitation on the present application. In the drawings: Figure 1 A structure schematic view of a part of a blade in an embodiment is shown; Figure 2 A structure slope view of a part of a blade in an embodiment is shown; Figure 3 A front view of a part of a blade in an embodiment is shown; Figure 4 A schematic view of the cooling air flow direction in an embodiment is shown; Figure 5 A structure schematic view of a cover plate in an embodiment is shown.

[0024] Reference signs: 1, blade wall; 2, first air film hole; 3, slot-shaped air film hole; 4, gas collecting cavity; 5, gas collecting groove; 6, cover plate. DETAILED DESCRIPTION

[0025] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0026] The present invention will be further described in detail below with reference to specific embodiments, which should not be construed as limiting the scope of protection claimed by the present invention.

[0027] Example According to one aspect of the present invention, a gas turbine blade, such as Figures 1-3 As shown, the blade includes a blade wall 1, an internal chamber, a plurality of first film gas holes 2, and at least one grooved film gas hole 3. The internal chamber is located inside the blade. The blade also includes a gas collecting chamber 4. The first film gas holes 2, the grooved film gas holes 3, and the gas collecting chamber 4 are all located on the blade wall 1. The gas collecting chamber 4 is fluidly connected to the internal chamber through the plurality of first film gas holes 2, and the gas collecting chamber 4 is fluidly connected to the outside of the blade through at least one grooved film gas hole 3.

[0028] It should be noted here that the fluid connectivity refers to connecting different containers or devices through pipes, pipelines, etc., to realize the transmission and distribution of fluids such as gases or liquids; in such a connectivity system, fluids such as gases or liquids can flow from one container to another or from one device to another under the action of pressure difference.

[0029] Specifically, such as Figure 4 As shown, the cooling airflow flows from the internal chamber through the first air film hole 2, the air collection chamber 4, and the grooved air film hole 3 to the outside of the blade.

[0030] Each of the first air film pores 2 is a pore structure with an equal cross-sectional area. Preferably, as follows: Figures 1-3 As shown, the cross-section of the first air film hole 2 is elliptical.

[0031] In other embodiments, the first gas film hole 2 may also be a gradually widening hole or a gradually narrowing hole along the direction of gas flow in the gas turbine gas flow channel.

[0032] The distance between two adjacent first air film holes 2 is 1-1.5 times the maximum inner diameter of the first air film hole 2. Preferably, the distance between two adjacent first air film holes 2 is 1.2 times the maximum inner diameter of the first air film hole 2.

[0033] The flow area of ​​the grooved air film orifice 3 is no greater than 1.2 times the total flow area of ​​all the first air film orifices 2. Preferably, the flow area of ​​the grooved air film orifice 3 is less than the total flow area of ​​all the first air film orifices 2.

[0034] It should be noted that the distance between two adjacent first gas film holes 2 refers to the distance between the cross-sectional centers of two adjacent first gas film holes. The flow area refers to the minimum cross-sectional area actually passed by the fluid flow in the passage.

[0035] The vane further comprises a gas collection groove 5 on the outer side of the vane wall 1 and a cover plate 6 on the outer side of the vane wall 1, the cover plate 6 covering a part of the gas collection groove 5, and the gas collection cavity 4 being located between the cover plate 6 and the bottom surface of the gas collection groove 5. The bottom surface of the gas collection groove 5 and the inner side of the cover plate 6 are both flat, the bottom surface of the gas collection groove 5 and the inner side of the cover plate 6 are parallel, and the height of the gas collection cavity 4 along the normal direction of the bottom surface of the gas collection groove 5 is constant.

[0036] Specifically, as shown in Figures 1-5 First, the gas collection groove 5 is processed on the outer side of the vane wall, and the first gas film hole 2 is punched on the gas collection groove 5, the cover plate 6 covers the gas collection groove 5 to form the gas collection cavity 4, and the cover plate 6 is welded with the vane wall 1 at the edge directly above the outlet of the first gas film hole 2, and the outer side of the cover plate 6 is flush with the outer side of the vane wall.

[0037] In other embodiments, the vane can not include the gas collection groove 5 and the cover plate 6, and the gas collection cavity 4, the first gas film hole 2, and the slot-shaped gas film hole 3 and other structures are realized by 3D printing technology.

[0038] The depth of the gas collection groove 5 accounts for 10% to 50% of the thickness of the vane wall 1 at the corresponding position. Preferably, the depth of the gas collection groove 5 accounts for 15% of the thickness of the vane wall 1 at the corresponding position.

[0039] The provision of the gas collection cavity can significantly reduce the turbulence degree of the gas flow outlet, and ensure the stability of the subsequent cold gas flow. The bottom surface area of the gas collection cavity 4 should be larger than the area of the cold gas inlet to ensure the gas collection effect. Specifically, the total cross-sectional area of the plurality of first gas film holes 2 near one end of the gas collection cavity 4 accounts for 30% to 50% of the bottom surface area of the gas collection groove 5. Preferably, the total cross-sectional area of the plurality of first gas film holes 2 near one end of the gas collection cavity 4 accounts for 40% of the bottom surface area of the gas collection groove 5, which can achieve better gas collection effect.

[0040] The slot-shaped gas film hole 3 is located between the side wall of the gas collection groove 5 and the cover plate 6. From one end close to the gas collection cavity 4 to one end close to the outside of the vane, the slot-shaped gas film hole 3 is inclined to the direction of the gas flow in the gas turbine gas flow passage. Specifically, as shown in Figures 1-4As shown, the side wall of the gas collecting groove 5 and the side of the cover plate 6 forming the slot-shaped film hole 3 are inclined to the direction of the gas flow in the gas turbine gas flow passage from the end close to the inner chamber to the end close to the outer part of the blade.

[0041] In other embodiments, the slot-shaped film hole 3 is located on the cover plate 6, and the slot-shaped film hole 3 penetrates the cover plate 6 and fluidly communicates the outer part of the blade and the gas collecting cavity 4. Specifically, one cover plate 6 can be provided with a plurality of slot-shaped film holes 3 to improve the heat dissipation efficiency.

[0042] The first film hole 2 is inclined to the direction of the gas flow in the gas turbine gas flow passage from the end close to the inner chamber to the end close to the gas collecting cavity 4. Specifically, as shown in the drawings, Figures 1-4 The inclination direction of the first film hole 2 is consistent with the inclination direction of the slot-shaped film hole 3.

[0043] The above technical solutions of the present application at least achieve the following technical effects: 1. In the present application, the gas collecting cavity is arranged in the blade wall, and the first gas hole and the slot-shaped gas hole are communicated through the gas collecting cavity, which improves the inlet gas flow stability of the slot-shaped film hole, the outlet flow is more stable, and the cold gas coverage effect is guaranteed.

[0044] 2. In the present application, the first film hole with a hole structure is combined with the slot-shaped film hole, which improves the cooling efficiency of the film hole while ensuring the strength of the blade.

[0045] 3. In the present application, the spacing between the first gas holes is small, the cooling is uniform, and the stress concentration problem caused by the large temperature difference of different parts of the blade is avoided.

[0046] 4. In the present application, the first film hole and the slot-shaped film hole can be machined respectively, which avoids machining special-shaped hole structure, and the shapes of the first film hole and the slot-shaped film hole are relatively simple, without machining precision problems, greatly reducing the machining difficulty.

[0047] The above is only a plurality of specific embodiments of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can make equivalent replacement or change according to the technical solutions and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

[0048] It is to be noted that, as used in this specification and the appended claims, the singular forms "a," "an" and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a component" can include a combination of two or more components. Additionally, the terms "first," "second," and the like, as used in this specification, can be used to describe various elements, and do not imply any particular order or chronology unless otherwise indicated by the context. Furthermore, the terms "include," "contain," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to those elements, but can include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "comprises... a" does not, without more constraints, exclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0049] Note that, in the description of the specification, the description using the terms "one embodiment", "some embodiments", "an example", "a specific example" or "some examples" etc. means that the particular feature, structure, material or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. Descriptive expressions of the above terms in the specification do not necessarily refer to the same embodiment or example. Moreover, the particular feature, structure, material or characteristic described can be combined in any appropriate manner in one or more embodiments or examples. Furthermore, the person skilled in the art can combine and combine the different embodiments or examples described in the specification and the features of the different embodiments or examples, without contradiction.

Claims

1. A gas turbine blade, comprising a blade wall (1), an internal chamber, a plurality of first film gas holes (2), and at least one grooved film gas hole (3), wherein the internal chamber is located inside the blade, characterized in that, It also includes an air collection chamber (4), the first air film hole (2), the grooved air film hole (3) and the air collection chamber (4) are all located on the blade wall (1), the air collection chamber (4) is fluidly connected to the internal chamber through multiple first air film holes (2), and the air collection chamber (4) is fluidly connected to the outside of the blade through at least one grooved air film hole (3).

2. The gas turbine blade according to claim 1, characterized in that, The multiple first air film pores (2) are all pore structures with equal cross-sectional area.

3. The gas turbine blade according to claim 2, characterized in that, The distance between two adjacent first air film holes (2) is 1-1.5 times the maximum inner diameter of the first air film hole (2).

4. The gas turbine blade according to claim 3, characterized in that, The flow area of ​​the groove-shaped air film hole (3) is no more than 1.2 times the total flow area of ​​all the first air film holes (2).

5. The gas turbine blade according to claim 4, characterized in that, From one end near the internal chamber to the other end near the gas collecting chamber (4), the first gas film hole (2) is inclined in the direction of gas flow in the gas turbine gas flow channel.

6. The gas turbine blade according to claim 5, characterized in that, From one end near the gas collecting chamber (4) to the other end near the outside of the blade, the grooved gas film hole (3) is inclined in the direction of gas flow in the gas turbine gas flow channel.

7. The gas turbine blade according to claim 6, characterized in that, It also includes an air collecting groove (5) and a cover plate (6), the air collecting groove (5) being located on the outer side of the blade wall (1), the cover plate (6) being located on the outer side of the blade wall (1), the cover plate (6) covering a part of the air collecting groove (5), and the air collecting chamber (4) being located between the cover plate (6) and the bottom surface of the air collecting groove (5).

8. The gas turbine blade according to claim 7, characterized in that, The depth of the gas collecting groove (5) is 10% to 50% of the thickness of the corresponding blade wall (1).

9. The gas turbine blade according to claim 8, characterized in that, The bottom surface of the gas collecting groove (5) and the inner surface of the cover plate (6) are both planes. The bottom surface of the gas collecting groove (5) and the inner surface of the cover plate (6) are parallel. The height of the gas collecting cavity (4) along the normal direction of the bottom surface of the gas collecting groove (5) is constant.

10. The gas turbine blade according to claim 9, characterized in that, The total cross-sectional area of ​​the plurality of first air film holes (2) near one end of the gas collecting chamber (4) accounts for 30% to 50% of the bottom area of ​​the gas collecting groove (5).

11. The gas turbine blade according to claim 10, characterized in that, The groove-shaped air film hole (3) is located between the side wall of the air collection groove (5) and the cover plate (6).

12. The gas turbine blade according to claim 11, characterized in that, The grooved air film hole (3) is located on the cover plate (6), and the grooved air film hole (3) penetrates the cover plate (6) and fluidly connects the outside of the blade and the air collection chamber (4).

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