Turbine blade and engine including turbine blade

Abstract

According to the present invention, a turbine blade comprises a hollow portion extending in a first direction, and is formed of a ceramic composite material. Fiber bundles constituting the ceramic composite material form a plurality of layers covering an exterior of the hollow portion. In one or more layers as counted from a wall surface of the hollow portion, the fiber bundles in an orientation orthogonal to a first direction are arranged so as to continuously surround the hollow portion. Alternatively, when a layer formed by, among the fiber bundles, a first fiber bundle oriented along the first direction is defined as a first layer, and a layer formed by, among the fiber bundles, a second fiber bundle in an orientation orthogonal to the first direction is defined as a second layer, the stacking ratio of the first layer and the second layer is n:1 (n being a natural number of 2 or greater). Alternatively, in at least one of a first region adjacent to a front end of the hollow portion, a second region adjacent to a rear end of the hollow portion, and a third region located between the second region and a rear edge portion of the turbine blade along a flow direction around the turbine blade, an auxiliary fiber bundle in an orientation orthogonal to the layer is further provided in addition to the fiber bundles.

Description

Turbine blade, and engine including the turbine blade 【0001】 The present disclosure relates to a turbine blade and an engine including the turbine blade. 【0002】 Patent Document 1 discloses a fiber preform for a hollow turbine engine vane having a primary fiber structure obtained by three-dimensional weaving. 【0003】 Japanese Patent Translation of PCT No. 2016-540147 【0004】 In an engine or the like including a turbine blade as described in Patent Document 1, in order to improve the performance of the engine or the like, it is necessary to reduce the cooling air flow rate of the turbine blade. Therefore, since there is a limit to the reduction amount at the heat-resistant temperature of the metal material, instead of the metal material, forming the turbine blade with a ceramic composite material having a high heat-resistant temperature has been considered. However, there is a problem that the fabric pattern of the base material of the ceramic composite material becomes a constraint and it is difficult to realize a desired three-dimensional blade shape. 【0005】 The present disclosure has been made in view of the above problems. An object thereof is to provide a turbine blade formed of a ceramic composite material having a desired three-dimensional blade shape, and an engine including the turbine blade. 【0006】 The turbine blade according to the present disclosure includes a hollow portion extending in a first direction and is formed of a ceramic composite material. The fiber bundles constituting the ceramic composite material form a plurality of layers covering the outside of the hollow portion. In one or more layers counted from the wall surface of the hollow portion, the fiber bundles in a direction orthogonal to the first direction are arranged so as to continuously surround the hollow portion. 【0007】The turbine blade according to this disclosure has a hollow portion extending in a first direction and is formed of a ceramic composite material. The fiber bundles constituting the ceramic composite material form a plurality of layers covering the outside of the hollow portion. The layer formed by the first fiber bundle oriented along the first direction is designated as the first layer, and the layer formed by the second fiber bundle oriented perpendicular to the first direction is designated as the second layer. Along the flow direction around the turbine blade, the ratio of the stacking of the first and second layers at the trailing edge of the turbine blade may be n:1 (where n is a natural number of 2 or more). 【0008】 The turbine blade according to this disclosure comprises a hollow portion extending in a first direction and is formed of a ceramic composite material. The fiber bundles constituting the ceramic composite material form a plurality of layers covering the outside of the hollow portion. Along the flow direction around the turbine blade, in at least one of a first region adjacent to the front end of the hollow portion, a second region adjacent to the rear end of the hollow portion, and a third region located between the second region and the trailing edge of the turbine blade, auxiliary fiber bundles oriented perpendicular to the layers may be further provided in addition to the fiber bundles. 【0009】 The engine may also be equipped with the turbine blades described above. 【0010】 According to this disclosure, it is possible to provide a turbine blade formed from a ceramic composite material having a desired three-dimensional blade shape, and an engine equipped with the turbine blade. 【0011】 This is a schematic diagram showing a turbine blade according to the present disclosure. This is a cross-sectional view showing a turbine blade according to the present disclosure. This is a schematic diagram showing an example of the arrangement of the first fiber bundle. This is a schematic diagram showing an example of the arrangement of the second fiber bundle. This is an enlarged view of the first main part showing a cross-section of the turbine blade. This is an enlarged view of the second main part showing a cross-section of the turbine blade. 【0012】 Several exemplary embodiments will be described below with reference to the drawings. Common parts in each drawing are denoted by the same reference numerals, and redundant explanations will be omitted. 【0013】[Turbine Blade Structure] Figure 1 is a schematic diagram showing a turbine blade according to the present disclosure. As shown in Figure 1, the turbine blade 1 has a hollow section HP extending in a first direction AR1 and is formed of a ceramic composite material CM. Note that the shape of the turbine blade 1 shown in Figure 1 is schematic, and the shape of the turbine blade 1 actually manufactured is not limited to the example given herein. 【0014】 For example, the turbine blade 1 may be provided on an engine. The engine may be an internal combustion engine that obtains rotational kinetic energy by rotating a turbine with high-temperature gas generated by the combustion of fuel or the like. 【0015】 The hollow section HP is a region consisting of a cavity through which a fluid for cooling the turbine blade 1 flows. In recent developments, the temperature of the gas introduced into the turbine has tended to be higher. Recently, in addition to improving the heat resistance temperature of the turbine blade 1 itself, a hollow structure has been incorporated into the turbine blade 1 to cope with these high temperatures. 【0016】 Ceramic composite material CM is a material formed by compounding a fiber bundle made of ceramic fibers with a ceramic substrate (matrix). Ceramic composite material CM has excellent heat resistance, high-temperature strength, and toughness, and is characterized by being lightweight and high-strength. By improving the heat resistance temperature of the turbine blade 1 itself, it becomes possible to reduce the cooling air flow rate of the turbine blade 1. As a result, it can contribute to improving the performance of engines and other devices equipped with the turbine blade 1. 【0017】 The fiber bundles contained in the ceramic composite material CM may be, for example, silicon carbide fiber bundles. Furthermore, the fiber bundles may be coated with a boron nitride interface. The ceramic substrate may be formed by chemical vapor infiltration (CVI) or low-temperature melt infiltration (LMI). 【0018】 Figure 2 is a cross-sectional view showing a turbine blade according to the present disclosure. Figure 2 shows a cross-section of the turbine blade 1 in a plane perpendicular to the first direction AR1. 【0019】Furthermore, Figure 3 is a schematic diagram showing an example of the arrangement of the first fiber bundle. Figure 4 is a schematic diagram showing an example of the arrangement of the second fiber bundle. Figures 3 and 4 show the view of the fiber bundle layers when the vertical direction of the paper is the first direction AR1, corresponding to the line of sight in Figure 1. In addition, Figures 2 to 4 show the flow direction FR of the fluid flowing around the turbine blade 1. 【0020】 The fiber bundles constituting the ceramic composite material CM form one or more layers covering the outside of the hollow portion HP. Here, "layer" refers to a group composed of multiple fiber bundles. For example, as will be described later with reference to Figures 3 and 4, the fiber bundles contained within the same "layer" are aligned in their longitudinal direction and extend in the same direction. 【0021】 "Covering the outside of the hollow section" means that the layer surrounds the outer periphery of the hollow section HP. As shown in Figures 3 and 4, the layer surrounds the outer periphery of the hollow section HP in a cross section perpendicular to the first direction AR1, forming a closed curve, and the hollow section HP is located inside the closed curve. 【0022】 Multiple layers, as shown in Figures 3 and 4, are arranged around the hollow section HP. For example, the layers shown in Figure 3 and the layers shown in Figure 4 may be arranged alternately. Alternatively, a structure obtained by stacking multiple layers shown in Figure 3 and multiple layers shown in Figure 4 may be repeatedly arranged around the hollow section HP. 【0023】 The layer shown in Figure 3 consists of a plurality of first fiber bundles FB1 oriented along the first direction AR1. The first fiber bundles FB1 may be continuous from one end to the other of the turbine blade 1 in the first direction AR1. Here, "one end" refers to the upper part of the turbine blade 1 shown in Figure 1, and "the other end" refers to the lower part of the turbine blade 1 shown in Figure 1. 【0024】 Because the first fiber bundle FB1 is continuous from one end to the other of the turbine blade 1 in the first direction AR1, the ceramic composite material CM is reinforced by multiple first fiber bundles FB1 that are seamlessly connected from one end to the other of the turbine blade 1. As a result, the durability of the turbine blade 1 is improved and high strength is achieved. 【0025】Furthermore, the number of first fiber bundles FB1 may be constant in any cross-section perpendicular to the first direction AR1. Since the number of first fiber bundles FB1 is constant, it is guaranteed that each first fiber bundle FB1 is continuously connected from one end to the other of the turbine blade 1. 【0026】 The layer shown in Figure 4 consists of a plurality of second fiber bundles FB2 oriented perpendicular to the first direction AR1. The second fiber bundles FB2 are arranged to surround the hollow portion HP. Therefore, when viewed in a cross-section perpendicular to the first direction AR1, the second fiber bundles FB2 form a closed curve with the hollow portion HP inside. 【0027】 Since the second fiber bundle FB2 is arranged to surround the hollow section HP, the ceramic composite material CM is reinforced by multiple second fiber bundles FB2 that are continuous along the circumferential direction of the hollow section HP. As a result, the durability of the turbine blade 1 is improved and high strength is achieved. In particular, the occurrence of cracks around the hollow section HP is suppressed. 【0028】 Figure 5 is a first enlarged view showing a cross-section of the turbine blade. Figure 5 shows an enlarged view of region A1 shown in Figure 2. In Figure 5, the cross-section of the turbine blade 1 is shown in a plane perpendicular to the first direction AR1, with the first fiber bundle FB1 being a rectangle and the second fiber bundle FB2 being a solid line. For example, in region A1, layers consisting of multiple first fiber bundles FB1 and layers consisting of multiple second fiber bundles FB2 are alternately stacked. 【0029】 In Figure 2, in region Z1, which is arranged around the hollow portion HP, the second fiber bundle FB2 is arranged to continuously surround the hollow portion HP. In region Z1, one or more layers are arranged counting from the wall surface of the hollow portion HP, and each layer is arranged to continuously surround the hollow portion HP. 【0030】For example, in one or more layers counting from the wall surface of the hollow section HP, the second fiber bundle FB2 may be formed in a helical or loop shape. To form it in a "helical" shape, a continuous second fiber bundle FB2 may be wrapped around the hollow section HP multiple times, and the wrapped second fiber bundle FB2 may form the layer shown in Figure 4. Alternatively, to form it in a "loop" shape, a few ring-shaped second fiber bundles FB2 without ends may be wrapped around the section, and the wrapped second fiber bundle FB2 may form the layer shown in Figure 4. 【0031】 On the other hand, in region Z2 arranged along the surface of the turbine blade 1, the second fiber bundle FB2 is arranged to surround the hollow portion HP, but the second fiber bundle FB2 is discontinuous at the trailing edge of the turbine blade 1 along the flow direction FR around the turbine blade 1. 【0032】 Figure 6 is a second enlarged view of a key part showing a cross-section of the turbine blade. Figure 6 shows an enlarged view of the region A2 shown in Figure 2. In Figure 6, the cross-section of the turbine blade 1 is shown in a plane perpendicular to the first direction AR1, with the first fiber bundle FB1 being a rectangle and the second fiber bundle FB2 being a solid line. As shown in Figure 6, the second fiber bundle FB2 is discontinuous at the trailing edge of the turbine blade 1 along the flow direction FR. 【0033】 Furthermore, at the trailing edge of the turbine blade 1, there may be sections where layers consisting of multiple first fiber bundles FB1 and layers consisting of multiple second fiber bundles FB2 are not alternately stacked. For illustrative purposes, the layer formed by the first fiber bundles FB1 will be referred to as the first layer, and the layer formed by the second fiber bundles FB2 will be referred to as the second layer. For example, at the trailing edge of the turbine blade 1, the stacking ratio of the first layer to the second layer may be n:1 (where n is a natural number of 2 or more). 【0034】 As shown in Figure 6, the first and second layers may be stacked such that the stacking ratio of the first and second layers changes from 1:1 to n:1 (where n is a natural number greater than or equal to 2) as you approach the trailing edge of the turbine blade 1. 【0035】In addition, the turbine blade 1 may further include auxiliary fiber bundles oriented perpendicular to the layers formed by the first fiber bundle FB1 and the second fiber bundle FB2, in addition to the first fiber bundle FB1 and the second fiber bundle FB2. 【0036】 For example, the turbine blade 1 may be provided with auxiliary fiber bundles that are substantially perpendicular to regions Z1 and Z2, as shown by the thick lines in the first region R1 in Figure 2. Here, the first region R1 is the region adjacent to the leading end of the hollow section HP along the flow direction FR around the turbine blade 1. By providing auxiliary fiber bundles, the occurrence of cracks around the leading edge of the turbine blade 1 and the hollow section HP is suppressed. This improves the durability of the turbine blade and achieves high strength. 【0037】 Furthermore, as shown by the thick line in the second region R2 in Figure 2, the turbine blade 1 may also be provided with auxiliary fiber bundles that are substantially perpendicular to regions Z1 and Z2. Here, the second region R2 is the region adjacent to the trailing end of the hollow section HP along the flow direction FR around the turbine blade 1. By providing auxiliary fiber bundles, the occurrence of cracks around the hollow section HP is suppressed. The durability of the turbine blade is improved, and high strength is achieved. In particular, the second region R2 is the region where the layers included in region Z1 and the layers included in region Z2 diverge, and stress tends to concentrate there. By providing auxiliary fiber bundles, the durability against stress is improved. 【0038】 Furthermore, as shown by the thick line in the third region R3 in Figure 2, the turbine blade 1 may be provided with an auxiliary fiber bundle that is substantially perpendicular to region Z2 and passes through region Z3. Here, the third region R3 is a region located between the second region R2 and the trailing edge of the turbine blade 1, along the flow direction FR around the turbine blade 1. By providing the auxiliary fiber bundle, the occurrence of cracks around the trailing edge of the turbine blade 1 is suppressed. The durability of the turbine blade is improved, and high strength is achieved. In particular, the third region R3 is a region where layers included in region Z2 merge, and stress tends to concentrate there. By providing the auxiliary fiber bundle, the durability against stress is improved. 【0039】[Effects of the Embodiment] As described in detail above, the turbine blade according to the present disclosure has a hollow portion extending in a first direction and is formed of a ceramic composite material. The fiber bundles constituting the ceramic composite material form a plurality of layers covering the outside of the hollow portion. In one or more layers counting from the wall surface of the hollow portion, fiber bundles oriented perpendicular to the first direction are arranged to continuously surround the hollow portion. 【0040】 This makes it possible to provide a turbine blade formed from a ceramic composite material having a desired three-dimensional blade shape, and an engine equipped with the turbine blade. It can achieve excellent heat resistance, high-temperature strength, and toughness, as well as being lightweight and high-strength. 【0041】 Furthermore, the ceramic composite material is reinforced by continuous fiber bundles along the circumferential direction of the hollow section, improving the durability of the turbine blades and achieving high strength. In particular, the occurrence of cracks around the hollow section is suppressed. 【0042】 The turbine blade according to this disclosure has a hollow portion extending in a first direction and is formed of a ceramic composite material. The fiber bundles constituting the ceramic composite material form a plurality of layers covering the outside of the hollow portion. The layer formed by the first fiber bundle oriented along the first direction is designated as the first layer, and the layer formed by the second fiber bundle oriented perpendicular to the first direction is designated as the second layer. Along the flow direction around the turbine blade, the ratio of the stacking of the first and second layers at the trailing edge of the turbine blade may be n:1 (where n is a natural number of 2 or more). 【0043】 This allows for an increase in the proportion of the first fiber bundle at the trailing edge of the turbine blade, reinforcing the ceramic composite in the first direction (AR1). As a result, the durability of the turbine blade is improved, and high strength is achieved. In particular, the occurrence of cracks at the trailing edge of the turbine blade is suppressed. 【0044】Furthermore, while reinforcing with the first fiber bundle, the proportion of the second fiber bundle can be reduced, so that it is possible to avoid an increase in the thickness of the turbine blade 1 at the trailing edge of the turbine blade. As a result, while realizing a desired three-dimensional blade shape, high strength at the trailing edge of the turbine blade can be realized. 【0045】 The turbine blade according to the present disclosure includes a hollow portion extending in the first direction and is formed of a ceramic composite material. The fiber bundles constituting the ceramic composite material form a plurality of layers covering the outside of the hollow portion. Along the flow direction around the turbine blade, at least any one of a first region adjacent to the front end of the hollow portion, a second region adjacent to the rear end of the hollow portion, and a third region located between the second region and the trailing edge of the turbine blade, in addition to the fiber bundles, auxiliary fiber bundles in a direction orthogonal to the layers may be further provided. 【0046】 Thereby, a portion where stress is likely to concentrate in the turbine blade 1 can be reinforced by the auxiliary fiber bundles. The durability of the turbine blade is improved and high strength is realized. Since the auxiliary fiber bundles have a direction orthogonal to the layers, the strength of the turbine blade can be improved against stress acting in a direction to peel the layers from each other. 【0047】 The engine may include the above-described turbine blade. Thereby, while realizing the characteristics of excellent heat resistance, high temperature strength, toughness, light weight and high strength by the ceramic composite material, a highly efficient engine can be realized. 【0048】 According to the present disclosure, while enhancing the durability of the turbine blade, the performance of an engine or the like including the turbine blade can be improved. Therefore, for example, it can contribute to Goal 9 of the Sustainable Development Goals (SDGs) led by the United Nations, "Build resilient infrastructure, promote inclusive and sustainable industrialization, and foster innovation." 【0049】Although several embodiments have been described, it is possible to modify or transform the embodiments based on the above disclosure. All components of the above embodiments, and all features described in the claims, may be taken individually and combined, provided that they do not conflict with each other. 【0050】 The entire contents of Japanese Patent Application No. 2024-218678 (Filing Date: December 13, 2024) are incorporated herein by reference. 【0051】 1. Turbine blade AR1 First direction CM Ceramic composite FB1 First fiber bundle FB2 Second fiber bundle FR Flow direction HP Hollow section R1 First region R2 Second region R3 Third region Z1-Z3 regions

Claims

1. A turbine blade formed of a ceramic composite material, comprising a hollow portion extending in a first direction, wherein the fiber bundles constituting the ceramic composite material form a plurality of layers covering the outside of the hollow portion, and in one or more of the layers counting from the wall surface of the hollow portion, the fiber bundles oriented perpendicular to the first direction are arranged to continuously surround the hollow portion.

2. A turbine blade formed of a ceramic composite material, having a hollow portion extending in a first direction, wherein the fiber bundles constituting the ceramic composite material form a plurality of layers covering the outside of the hollow portion, the layer formed by a first fiber bundle oriented along the first direction is designated as the first layer, and the layer formed by a second fiber bundle oriented perpendicular to the first direction is designated as the second layer, and the ratio of the lamination of the first layer to the second layer at the trailing edge of the turbine blade along the flow direction around the turbine blade is n:1 (where n is a natural number of 2 or more).

3. A turbine blade formed of a ceramic composite material, comprising a hollow portion extending in a first direction, wherein the fiber bundles constituting the ceramic composite material form a plurality of layers covering the outside of the hollow portion, and in at least one of a first region adjacent to the front end of the hollow portion, a second region adjacent to the rear end of the hollow portion, and a third region located between the second region and the trailing edge of the turbine blade, auxiliary fiber bundles are further provided in addition to the fiber bundles, oriented perpendicular to the layers.

4. An engine comprising a turbine blade as described in any one of claims 1 to 3.

Images