Turbo machine component with film-cooling hole with hood extending from wall outer surface

Abstract

To provide a turbo machine component with a film-cooling hole with a hood extending from a wall outer surface.SOLUTION: A turbomachine component has a wall outer surface and an internal coolant source. A film-cooling hole is in the wall and extends from an internal coolant source to the wall outer surface. The film-cooling hole includes a metering section in fluid communication with the internal coolant source, and a diffuser section in fluid communication with the metering section and including a first internal surface spaced from a second internal surface. A coating collector which receives part of a coating in the wall is part of the diffuser section. The film-cooling hole also includes a hood section including a member extending outwardly from the wall outer surface. The member may include a hood internal surface continuous with the first internal surface of the diffuser section and a hood outer surface parallel to the wall outer surface. The hood section reduces, and possibly prevents, the coating from filling the film-cooling hole during application thereof.SELECTED DRAWING: Figure 9

Description

[Technical field]

[0001] The present disclosure relates generally to component cooling and, more particularly, to a turbomachine component including a film cooling hole including a hood extending from an exterior wall surface of the turbomachine component. [Background technology]

[0002] Certain industrial components require cooling during operation. For example, turbomachine components, such as the nozzles or blades of a gas turbine, require cooling because they are exposed to hot combustion gases and have operating temperatures that can approach or exceed the melting temperature of metals. One form of cooling is film cooling, in which a coolant, such as air, is discharged from film cooling holes in the outer surface of the wall of the component. The coolant is directed across the outer surface as a film by the hot combustion gases flowing along the outer surface of the component, cooling the outer surface of the component.

[0003] Protective coatings, such as ceramic thermal barrier coatings, are also used on the exterior surfaces of turbine components to protect them from thermal damage. During component manufacturing, film cooling holes are formed and a coating is applied over the holes, which later requires the coating to be removed from each individual hole, for example, using a drilling process. The drilling process can damage the coating and / or the film cooling holes and is time consuming and costly.

[0004] To speed up the drilling process, film cooling holes are often configured in straight lines, limiting the ability to place the film cooling holes in locations that are most advantageous for cooling. Various attempts have been made to form film cooling holes that do not fill with the applied coating or to provide masks to prevent coating from entering the holes, but challenges remain. Summary of the Invention

[0005] All aspects, examples and features described below can be combined in any manner that is technically possible.

[0006] One aspect of the disclosure provides a turbomachine component including a wall including a wall outer surface and an internal coolant source, and a film-cooling hole in the wall and extending from the internal coolant source to the wall outer surface, the film-cooling hole including a metering section in fluid communication with the internal coolant source, a diffuser section in fluid communication with the metering section and including a first internal surface and including a coating collector, and a hood section including a member extending outwardly from the wall outer surface. The member including a hood internal surface contiguous with the first internal surface of the diffuser section and a hood outer surface parallel to the wall outer surface.

[0007] Another aspect of the disclosure includes any of the preceding aspects, wherein the coating collector includes a portion of a second internal surface of the diffuser section spaced from the first internal surface, the portion of the second internal surface having a first end intersecting the wall outer surface and forming a downstream edge of the film-cooling hole and a second end that transitions to one the metering section and another portion of the second internal surface.

[0008] Another aspect of the present disclosure includes any of the preceding aspects, wherein the member of the hood section further includes a hood back surface connecting the hood outer surface and the wall outer surface.

[0009] Another aspect of the present disclosure includes any of the preceding aspects, and further includes a coating on the wall outer surface, on the hood back surface, and in the coating collector.

[0010] Another aspect of the present disclosure includes any of the preceding aspects, wherein a distance between the hood outer surface and the wall outer surface is less than or equal to a thickness of the coating.

[0011] Another aspect of the present disclosure includes any of the preceding aspects, wherein a depth of the coating collector is greater than or equal to a thickness of the coating.

[0012] Another aspect of the present disclosure includes any of the preceding aspects, wherein the hood outer surface extends through the coating.

[0013] Another aspect of the present disclosure includes any of the preceding aspects, wherein the hood internal surface intersects the hood outer surface forming an upstream edge of the film-cooling hole.

[0014] Another aspect of the present disclosure includes any of the preceding aspects, wherein the metering section has a smaller cross-sectional area than the diffuser section.

[0015] Another aspect of the present disclosure includes any of the preceding aspects, wherein the diffuser section further includes opposing side surfaces connecting the first and second internal surfaces and diverging from one another toward an outlet of the film-cooling hole.

[0016] Another aspect of the present disclosure includes any of the preceding aspects, wherein the hood section further includes side walls coupling opposing sides of the member to the wall outer surface.

[0017] Another aspect of the present disclosure includes any of the preceding aspects, wherein the member of the hood section extends from the wall outer surface at an obtuse angle greater than 120° and less than 180°.

[0018] Another aspect of the present disclosure includes any of the preceding aspects, wherein the wall and the film-cooling hole are additively manufactured, and the turbomachine component comprises an airfoil having the wall and the film-cooling hole.

[0019] A turbomachine component of one aspect of the disclosure includes a wall including a wall outer surface and an internal coolant source, and a film-cooling hole in the wall and extending from the internal coolant source to the wall outer surface, the film-cooling hole having a cross-sectional area greater than the metering section, the film-cooling hole including: (a) a metering section in fluid communication with the internal coolant source; and (b) a diffuser section in fluid communication with the metering section and including a first internal surface spaced from a second internal surface and including a coating collector, the diffuser section having a larger cross-sectional area than the metering section. (c) a hood section including a member extending outwardly from the wall outer surface, the member including a hood outer surface parallel to the wall outer surface, and a hood back surface connecting the hood outer surface and the wall outer surface.and the member including a hood outer surface parallel to the wall outer surface and a hood back surface connecting the hood outer surface and the wall outer surface, and the turbomachine component includes a coating on the wall outer surface, on the hood back surface, and in the coating collector, wherein the hood outer surface extends through the coating.

[0020] Another aspect of the disclosure includes any of the preceding aspects, wherein the coating collector includes a portion of a second internal surface of the diffuser section spaced from the first internal surface, the portion of the second internal surface having a first end intersecting the wall outer surface and forming a downstream edge of the film-cooling hole and a second end that transitions to one the metering section and another portion of the second internal surface.

[0021] Another aspect of the present disclosure includes any of the preceding aspects, wherein the member of the hood section further includes a hood internal surface contiguous with the first internal surface of the diffuser section, the hood internal surface intersects the hood outer surface forming an upstream edge of the film-cooling hole, the metering section intersects the coating collector at an internal edge, and the upstream edge is over the internal edge.

[0022] Another aspect of the present disclosure includes any of the preceding aspects, wherein the distance between the hood exterior surface and the wall exterior surface is less than or equal to a thickness of the coating.

[0023] Another aspect of the present disclosure includes any of the preceding aspects, wherein a depth of the coating collector is equal to or greater than a thickness of the coating.

[0024] Another aspect of the present disclosure includes any of the preceding aspects, wherein the hood section further includes sidewalls joining opposing sides of the member to the wall exterior surface.

[0025] Another aspect of the present disclosure includes any of the preceding aspects, wherein the members of the hood section extend from the wall exterior surface at an obtuse angle greater than 120° and less than 180°.

[0026] Two or more aspects described in this disclosure, including those described in this Summary, may be combined to form embodiments not specifically described herein, i.e., all embodiments described herein may be combined with each other.

[0027] The details of one or more implementations are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will become apparent from the description and drawings, and from the claims. [Brief description of the drawings]

[0028] These and other features of the present disclosure will be more readily understood from the following detailed description of the various aspects of the disclosure taken in conjunction with the accompanying drawings illustrating various embodiments of the present disclosure.

[0029] [Figure 1] 1 is a schematic diagram of an exemplary industrial machine in the form of a gas turbine system. [Diagram 2] 2 is a cross-sectional view of an exemplary turbine assembly that may be used with the gas turbine system of FIG. 1. [Diagram 3] 1 is a perspective view of an exemplary component in the form of a turbine rotor blade in which embodiments of the present disclosure may be employed; [Figure 4] 1 illustrates a perspective view of an exemplary component in the form of a turbine nozzle of a type in which embodiments of the present disclosure may be employed; [Diagram 5] 1 illustrates a cross-sectional view of a component including a film cooling hole having a coating thereon in accordance with an embodiment of the present disclosure. [Figure 6] 6 illustrates a cross-sectional view of the component of FIG. 5 including a film cooling hole without a coating thereon, according to an embodiment of the present disclosure. [Figure 7] 3 illustrates a cross-sectional view of a component including a film cooling hole having a coating thereon in accordance with an alternative embodiment of the present disclosure. [Figure 8] 8 illustrates a cross-sectional view of the component of FIG. 7 including a film cooling hole without a coating thereon in accordance with an alternative embodiment of the present disclosure. [Figure 9] 1 illustrates a top view of a component including uncoated film cooling holes according to an embodiment of the present disclosure. [Figure 10] 6 illustrates a cross-sectional view of the component of FIG. 5 including a coated film cooling hole according to an embodiment of the present disclosure. [Figure 11] 8 illustrates a cross-sectional view of the component of FIG. 7 including a film cooling hole having a coating thereon, according to an embodiment of the present disclosure. [Figure 12] FIG. 1 is a perspective view of a component including an uncoated film cooling hole according to an embodiment of the present disclosure. [Figure 13] 1 illustrates a top view of a component including a film cooling hole having a coating thereon in accordance with an embodiment of the present disclosure; and [Figure 14] 1A-1D show cross-sectional views of a component including film cooling holes in accordance with various alternative embodiments of the present disclosure; [Figure 15] 1A-1D show cross-sectional views of a component including film cooling holes in accordance with various alternative embodiments of the present disclosure; [Figure 16] 1A-1D show cross-sectional views of a component including film cooling holes in accordance with various alternative embodiments of the present disclosure; [Figure 17] 1A-1D show cross-sectional views of a component including film cooling holes in accordance with various alternative embodiments of the present disclosure;

[0030] It should be noted that the drawings of the present disclosure are not necessarily to scale. The drawings are intended to depict only typical aspects of the present disclosure and therefore should not be considered as limiting the scope of the present disclosure. In the drawings, like numbers represent like elements between the drawings. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] As a first matter, in order to clearly explain this disclosure, it becomes necessary to select certain terms when referring to and describing relevant components within an exemplary application of such components, such as turbine components. In so doing, common industry terms are used, where possible, and employed in a manner consistent with their common meaning. Unless otherwise specified, such terms should be given a broad interpretation consistent with the context of this application and the scope of the appended claims. Those skilled in the art will appreciate that certain components are often referred to using multiple different or overlapping terms. What is described herein as a single component may include and be referred to as being made up of multiple components in other contexts. Alternatively, what is described herein as including multiple components may be referred to as a single component elsewhere.

[0032] Additionally, several descriptive terms may be used periodically herein and it may be helpful to define these terms at the beginning of this section. These terms and their definitions are as follows, unless otherwise noted: As used herein, "downstream" and "upstream" are terms that indicate a direction relative to the flow of a fluid, such as the hot combustion gases along the exterior surface of a turbine component or, for example, the flow of cooling water through one of the components of a turbomachine. The term "downstream" corresponds to the direction of fluid flow and the term "upstream" refers to the opposite direction to the flow. The terms "forward" and "aft" refer to directions, without further specification, with "forward" referring to the forward or compressor end of the turbomachine and "aft" referring to the aft or turbine end of the turbomachine.

[0033] It is often necessary to describe components at different radial locations relative to a central axis. The term "axial" refers to movement or location parallel to an axis, e.g., the axis of a turbomachine. The term "radial" refers to movement or location perpendicular to an axis, e.g., the axis of a turbomachine. In such cases, if a first component is located closer to the axis than a second component, the specification states that the first component is "radially inside" or "inboard" the second component. On the other hand, if a first component is located farther from the axis than the second component, the specification may state that the first component is "radially outside" or "outboard" the second component. Finally, the term "circumferential" refers to movement or location about an axis, e.g., the circumferential inner surface of a casing that extends about the axis of a turbomachine. As indicated above, it will be understood that such terms may be applied in relation to the axis of a turbomachine.

[0034] Furthermore, certain descriptive terms may be used regularly in this specification, as explained below: The terms "first," "second," and "third" may be used interchangeably to distinguish one component from another, and are not intended to imply any position or importance of the individual components.

[0035] The terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural unless the context clearly indicates otherwise. It will be further understood that as used herein, the terms "comprises" and / or "comprising" specify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. "Optionally" or "optionally" means that the subsequently described event may or may not occur, or the subsequently described feature may or may not be present, and that the description includes examples in which the event occurs or the feature is present and examples in which the event does not occur or the feature is not present.

[0036] When an element or layer is referred to as being "on," "engaged," "connected," "coupled," or "attached" to another element or layer, it may be directly engaged, connected, coupled, or attached to the other element or layer, or there may be intervening elements or layers. In contrast, when an element is described as "directly resting," "directly engaged," "directly coupled," or "directly coupled" on another element or layer, there are no intervening elements or layers. Other words used to describe relationships between elements should be interpreted similarly (e.g., "between" vs. "directly between," "adjacent" vs. "directly adjacent," etc.). As used herein, the term "and / or" includes any combination of one or more of the associated listed items. As used herein, the verb forms "couple" and "mount" may be used interchangeably.

[0037] As indicated above, the present disclosure provides a component, such as a turbine component, having a wall including a wall exterior surface and an internal coolant source. The component also includes a film cooling hole disposed in the wall and extending from the internal coolant source to the wall exterior surface. The film cooling hole includes a metering section in fluid communication with the internal coolant source and a diffuser section in fluid communication with the metering section and including a first inner surface and a coating collector. The coating collector receives a portion of the coating of the diffuser section. The film cooling hole also includes a hood section including a member extending outwardly from the wall exterior surface. The member can include a hood inner surface contiguous with the first inner surface of the diffuser section and a hood outer surface parallel to the wall exterior surface. The coating collector allows the hood section to function as a shadow mask having sharp edges that reduce and possibly prevent coating from filling the film cooling hole, e.g., the diffuser section and the metering section, thus reducing manufacturing time and costs and reducing waste.

[0038] FIG. 1 illustrates a schematic diagram of an exemplary industrial machine that may include components according to the teachings of the present disclosure. In this example, the machine includes a turbomachine 100 in the form of a combustion or gas turbine system. The turbomachine 100 includes a compressor 102 and a combustor 104. The combustor 104 includes a combustion region 106 and a fuel nozzle assembly 108. The turbomachine 100 also includes a turbine assembly 110 and a common compressor / turbine shaft or rotor 112. In one embodiment, the turbomachine 100 is a 7HA.03 engine available from General Electric Company, Greenville, South Carolina, USA. The present disclosure is not limited to a particular GT system and may be implemented in connection with other engines including, for example, other HA, F, B, LM, GT, TM and E class engine models from General Electric Company, as well as engine models from other companies. Additionally, the present disclosure is not limited to a particular turbomachine and may be applied to, for example, steam turbines, jet engines, compressors, turbofans, and the like. Additionally, the present disclosure is not limited to any particular turbomachine, but may be applicable to any industrial component requiring film cooling.

[0039] In operation, air flows through the compressor 102 and the compressed air is delivered to the combustor 104. Specifically, the compressed air is delivered to a fuel nozzle assembly 108 that is integral with the combustor 104. The assembly 108 is in flow communication with the combustion region 106. The fuel nozzle assembly 108 is also in flow communication with a fuel source (not shown in FIG. 1 ) and channels fuel and air to the combustion region 106. The combustor 104 ignites and burns the fuel. The combustor 104 is in flow communication with a turbine assembly 110 in which thermal energy of the gas stream is converted to mechanical rotational energy. The turbine assembly 110 includes a turbine 111 (i.e., an expansion turbine) that is rotatably coupled to and drives a rotor 112. The compressor 102 is also rotatably coupled to the rotor 112. In the exemplary embodiment, there are multiple combustor and fuel nozzle assemblies 108.

[0040] FIG. 2 illustrates a cross-sectional view of an exemplary turbine assembly 110 of turbomachine 100 (FIG. 1) that may be used with gas turbine system 100 of FIG. 1. A turbine 111 of turbine assembly 110 is coupled to a stationary casing 122 of turbomachine 100 and includes a row of nozzles or vanes 120 axially adjacent a row of rotating blades 124. The stationary vanes or nozzles 126 may be retained in turbine assembly 110 by a radially outer platform 128 and a radially inner platform 130. The row of blades 124 of turbine assembly 110 includes rotating blades 132 that are coupled to rotor 112 and rotate therewith. The rotating blades 132 may include a radially inner platform 134 (blade root) coupled to rotor 112 and an optional radially outer tip shroud 136 (blade tip). A circumferential turbine shroud 138, which may be comprised of multiple shroud segments and may further define a hot gas path through the turbine 111, may be disposed axially between the rotating blades 132 and the static nozzles 126. As used herein, the terms “hot gas path component” or “component” may collectively refer to the static nozzles 126 and the rotor blades 132, unless otherwise specified.

[0041] 3 and 4 illustrate example components, such as hot gas path components of a turbomachine, in which teachings of the disclosure may be employed. FIG. 3 illustrates a perspective view of a turbine blade 132 of a type in which embodiments of the disclosure may be employed. The turbine blade 132 includes a root 140 at which the blade 132 is attached to the rotor 112 (FIG. 2). The root 140 may include a dovetail 142 configured to attach to a corresponding dovetail slot in an outer periphery of a rotor wheel 144 (FIG. 2) of the rotor 112 (FIG. 2). The root 140 may further include a shank 146 extending between the dovetail 142 and a platform 148 disposed at the junction of the airfoil 150 and the root 140, the platform 148 defining a portion of an inboard boundary of a hot gas flow path through the turbine assembly 110. It will be appreciated that the airfoils 150 are the active components of the rotor blades 132 that interrupt the flow of working fluid 220 (FIG. 2), i.e., the hot combustion gases, and direct the rotor disk to rotate.

[0042] It will be seen that the airfoil 150 of the rotor blade 132 includes a concave pressure side (PS) outer wall 152 and circumferentially or laterally opposed convex suction side (SS) outer walls 154 that extend axially between opposing leading and trailing edges 156, 158, respectively. The sidewalls 152, 154 also extend radially from the platform 148 to an outboard tip 160, which may or may not include the tip shroud 136 (FIG. 2).

[0043] FIG. 4 illustrates a perspective view of a static nozzle 126 of a type in which an embodiment of the present disclosure may be employed. The static nozzle 126 includes an outer platform 170 to which the static nozzle 126 mounts to a stationary casing 122 (FIG. 2) of a turbomachine. The outer platform 170 may include any now known or later developed mounting configuration for mounting to a corresponding mounting in the casing. The static nozzle 126 may further include an inner platform 174 for positioning between the platforms 148 (FIG. 3) of adjacent turbine rotor blades 132 (FIG. 3). The platforms 170, 174 define respective portions of the outboard and inboard boundaries of the flowpath through the turbine assembly 110. It will be appreciated that the airfoil 176 is an active component of the static nozzle 126 that intercepts and directs the flow of the working fluid toward the turbine blades 132 (FIG. 3). It will be seen that the airfoil 176 of the static nozzle 126 includes a concave pressure side (PS) outer wall 178 and circumferentially or laterally opposed convex suction side (SS) outer walls 180 extending axially between opposed leading and trailing edges 182, 184, respectively. The side walls 178, 180 also extend radially from platform 170 to platform 174.

[0044] The disclosed embodiments described herein may include aspects applicable to either the turbine rotor blades 132 and / or the static nozzles 126. It is understood that the blades 132 or the nozzles 126 may include internal cooling structures including a source of coolant, such as passages, conduits, and one or more other structures that supply coolant to their surfaces for film cooling. The coolant may include air from the compressor 102, for example.

[0045] 5 and 6 show cross-sectional views of a component 200 including a film cooling hole 202 according to an embodiment of the present disclosure. FIG. 5 shows a cross-sectional view of the component 200 including a coating 204 on the film cooling hole 202, and FIG. 6 shows a cross-sectional view of the component 200 without the coating and the film cooling hole 202. The component 200 may include any industrial component where film cooling is desired. For example, the component 200 may include a nozzle 126 or a blade 132, as previously described (see film cooling hole 202 in FIGS. 3 and 4).

[0046] Component 200 includes a wall 210 including a wall exterior surface 212 and an internal coolant source 214. Wall 210 can have any thickness necessary for operation of component 200. Internal coolant source 214 can include any open space, conduit, passage, etc. through which coolant may be supplied to wall 210. Wall interior surface 216 is an exterior surface of coolant source 214 that supplies pressurized coolant. In turbomachine applications, the coolant may be compressed air, for example, from compressor 102 (FIG. 1). Other coolants may also be supplied. Coolant source 214 can take various forms within component 200, such as, for example, a chamber, passage, conduit and various other open spaces defined within component 200. In the example turbomachine 100 (FIG. 1) described herein, the internal coolant source 214 may be passages defined in the nozzle 126 or blade 132 through which coolant (arrows in FIG. 5) may pass. Although the film cooling holes 202 are shown in the airfoils 150, 176 of the blade 132 and nozzle 126 in FIGS. 3 and 4, the film cooling holes 202 may be located anywhere in the blade 132 and nozzle 126, or any component 200 where film cooling would be employed, i.e., where a gas flow, such as the hot combustion gas flow 220 (FIGS. 2 and 5), would direct the coolant along the surface to be cooled.

[0047] The film cooling holes 202 are in the wall 210. More specifically, the film cooling holes 202 are defined in the wall 210 and extend from an internal coolant source 214, i.e., a wall inner surface 216 thereof, to a wall outer surface 212. In this manner, coolant supplied to the internal coolant source 214 passes through the wall 210 to cool the wall 210 and may then be directed by the hot combustion gas flow 220 of the turbomachine 100 ( FIG. 1 ) along the wall outer surface 212, i.e., to cool the wall outer surface 212 covered by the coating 204.

[0048] The film cooling holes 202 are positioned such that the coating 204 can be formed thereon without having to remove the coating 204 from each hole 202 after application of the coating. The film cooling holes 202 include multiple sections. The metering or feed section 230 is in fluid communication with the internal coolant source 214. The metering or feed section 230 (hereinafter, "metering section 230") can have any cross-sectional shape, such as circular, elliptical, polygonal, etc., forming a cylindrical tube. The metering section 230 has a cross-sectional area for metering or regulating the flow of coolant (arrows) from the internal coolant source 214 in any desired manner, such as flow rate, volume, pressure, etc. The cross-sectional shape and area can be customized for a particular application. In FIGS. 5-6, the metering section 230 is illustrated as a straight tube, but can have a variety of alternative configurations as described herein (see, e.g., FIGS. 14-17).

[0049] From the metering section 230, the coolant flows into a diffuser section 240 in fluid communication with the metering section 230. The metering section 230 has a smaller cross-sectional area than the diffuser section 240. The diffuser section 240 begins to spread the coolant flow inside the outlet 254 of the film cooling hole 202. The diffuser section 240 includes a first inner surface 242 and a coating collector 246. The diffuser section 240 may also include a second inner surface 244 spaced apart from the first inner surface 242. A portion or portions of the second inner surface 244 may be used to define a portion of the coating collector 246. The coating collector 246 includes an opening or void that can receive the coating 204 and smoothly fuse with the metering section 230 or the portion 244A of the second inner surface 244.

[0050] In Figs. 5 and 6, the second inner surface 244 includes two portions 244A, 244B joined by a transition 248. As shown in Fig. 6, the first inner surface 242 and the second inner surface 244 (i.e., portions 244A, 244B) are offset from each other at an angle α (shown relative only for portion 244B). The portion 244A is immediately adjacent to the metering section 230 and joins its inner surface 232 at the inner edge 284. Thus, the portion 244A of the second inner surface 244 joins and is immediately adjacent to the metering section 230. The portion 244A diverges from the first inner surface 242 and may be at the same angle α as the portion 244B or may be at a different angle. The portion 244B is recessed relative to the portion 244A to form the coating collector 246, i.e., recessed portion 244B, and also diverges from the first inner surface 242. Recess 244B may be recessed by transition portion 248 relative to portion 244A by a distance D1. Distance D1 represents the depth of coating collector 246 and is configured to be equal to or greater than a thickness T1 ( FIG. 5 ) of coating 204 in coating collector 246. As shown, transition portion 248 has a length corresponding to distance D1. Portions 244A, 244B may be parallel to one another such that when coating 204 is disposed over recess 244B, its surface is coplanar with portion 244A.

[0051] 6, the first inner surface 242 and the second inner surface 244 (i.e., portions 244A, 244B) diverge from one another at an angle α (shown relative only for portion 244B). The axis of the metering section 230 has an angle β with the wall exterior surface 212. The first inner surface 242 has an angle γ with the wall exterior surface 212, and the second inner surface 244 has an angle δ with the wall exterior surface 212 (shown for portion 244B). The angles α, β, γ, and δ may be selected to provide coolant to the wall exterior surface 212 having the coating 204 thereon with desired properties, including but not limited to a desired pressure and direction. The angles α, β, γ, and δ can be selected depending on various parameters such as, but not limited to, the properties of the coolant (e.g., fluid composition, pressure, temperature, flow rate, etc.), the properties of the wall 210 (e.g., material, thickness, etc.), and the properties of the hot gas flow 220 (FIGS. 2, 5) (e.g., fluid composition, pressure, temperature, flow rate, etc.). In a non-limiting example, the angle α may be in the range of 5° to 20°, the angle β may be in the range of 10° to 50°, the angle γ may be in the range of 10° to 50°, and the angle δ may be in the range of 5° to 50°.

[0052] 7 and 8 show cross-sectional views of a component 200 including a film cooling hole 202 according to an alternative embodiment of the present disclosure. FIG. 7 shows a cross-sectional view of the component 200 including a coating 204 on the film cooling hole 202, and FIG. 8 shows a cross-sectional view of the component 200 and the film cooling hole 202 without the coating. FIG. 7 and FIG. 8 are identical to FIG. 5 and FIG. 6 except that the portion 244A of the second inner surface 244 is omitted. In contrast, the transition portion 248 meets the inner surface 232 of the metering section 230. Here, the distance D1 represents the depth of the coating collector 246 that is equal to or greater than the thickness T1 of the coating 204 in the coating collector 246. The transition portion 248 and the portion 244B of the second inner surface 244 are otherwise as described above.

[0053] FIG. 9 illustrates a top view of a component 200 including a film cooling hole 202 without a coating thereon, according to an embodiment of the present disclosure. As shown in FIG. 9, the diffuser section 240 may also include opposing side surfaces 250, 252 that intersect the inner surfaces 242, 244 and diverge from an axis A of the film cooling hole 202 toward an outlet 254. The opposing side surfaces 250, 252 may connect the first and second inner surfaces 242, 244 and diverge from one another toward the outlet 254 of the film cooling hole 202. In this manner, lateral divergence of the coolant is provided along the wall exterior surface 212. Each opposing side surface 250, 252 may diverge relative to the metering section axis A at an angle λ in the range of, for example, 5° to 30°. In an alternative embodiment, the opposing sides 250, 252 may also be parallel to one another (and axis A), for example, see Figures 14 and 16 (note that the sides are not labeled in Figures 14 and 16 for clarity). In an alternative embodiment (not shown), the opposing sides 250, 252 may be oriented at different angles relative to the metering section axis A, forming an asymmetric channel.

[0054] The coating collector 246 is defined by and can include a recess 244B in the second inner surface 244. The recess 244B thus forms part of the diffuser section 240 and part of the coating collector 246. The recess 244B has a first end 262 that intersects with the wall outer surface 212 and forms a downstream end 264 of the film cooling hole 202, and a second end 266 that transitions to a transition section 248. As mentioned above, the distance D1 between the portion 244A of the metering section 230 (FIGS. 7-8) or the second inner surface 244 (FIGS. 5-6) and the recess 244B of the coating collector 246 defines the depth of the coating collector 246. The distance D1 is equal to or greater than the thickness T1 of the coating 204 applied at that location, i.e., the inner edge 284, so that the coolant flows smoothly from the metering section 230 to the diffuser section 240.

[0055] The film cooling hole 202 also includes a hood section 270 that includes a member 272 extending outwardly from the wall exterior surface 212. The member 272 includes an inner hood surface 274 that is continuous with the first inner surface 242 of the diffuser section 240, and an outer hood surface 276. The outer hood surface 276 may be parallel to the wall exterior surface 212. The first inner surface 242 is inboard of the wall exterior surface 212 and the inner hood surface 274 is outboard of the wall exterior surface 212, forming a continuous surface. Although not necessary in all cases, the first inner surface 242 and the inner hood surface 274 can be coplanar, i.e., one continuous surface.

[0056] The member 272 of the hood section 270 further includes a hood underside 278 connecting the hood outer surface 276 and the wall outer surface 212. As shown in Figures 5 and 7, the coating 204 is on the wall outer surface 212, the hood underside 278, and within the coating collector 246 (i.e., within the recess 244B of the second inner surface 244). The distance D2 between the hood outer surface 276 and the wall outer surface 212 is less than or equal to the thickness T2 of the coating 204 at that location. The hood inner surface 274 intersects with the hood outer surface 276 forming an upstream edge 280 of the film cooling hole 202. As shown, the upstream end 280 is relatively sharp, for example, as shown in Figures 10 and 11, the upstream end 280 can have an angle ε in the range of 5° and 50°. In certain embodiments, as shown in Figures 5-8, 10 and 11, the upstream edge 280 is above and slightly downstream of an interior edge 284 defined between the transition portion 248 and the metering section 230 or portion 244B of the second interior surface 244.

[0057] 6 and 8, member 272 of hood section 270 extends from wall exterior surface 212 at an angle θ selected to adequately support coating 204 from hood section 270. In certain embodiments, angle θ may be an obtuse angle greater than 120° and less than 180°. In other embodiments, angle θ may range from 130° to 180°. In other embodiments, angle θ may range from 140° to 170°.

[0058] FIG. 12 illustrates a perspective view of a component 200 including a film cooling hole 202 without a coating thereon, according to an embodiment of the present disclosure. As shown in FIGS. 9 and 12, the hood section 270 may further include side walls 286, 288 coupling opposing sides of the member 272 to the wall exterior surface 212. In this manner, the hood section 270 prevents the coating 204 from entering the diffuser section 240 or the metering section 230 from its sides. As shown in FIG. 12, the sides 286, 288 may form a non-perpendicular angle η with respect to the wall exterior surface 212. In certain embodiments, the angle η may be greater than 90°. In other embodiments, the angle η may be in the range of 90° to 135°. Alternatively, the angle η may be in the range of 135° to 180°.

[0059] 10 and 11 show cross-sectional views of a component 200 including a film-cooling hole 202 immediately after application of a coating 204 according to an embodiment of the present disclosure. FIG. 10 shows the coating 204 on the embodiment of FIG. 5, and FIG. 11 shows the coating 204 on the embodiment of FIG. 7. As shown in FIGS. 10 and 11, the hood section 270 prevents the coating 204 from filling the diffuser section 240 and / or the metering section 230 during coating application, eliminating the need to individually reopen the film-cooling holes 202. The hood section 270 cantilevers outward from the wall exterior surface 212 such that it only partially extends over and covers the diffuser section 240. In this manner, the hood section 270 is not a complete mask in that it does not completely cover and does not extend completely over the diffuser section 240. Notably, the hood section 270 does not need to be removed and can remain as part of the component 200, reducing manufacturing time and costs and reducing waste (e.g., of removed mask parts).

[0060] The component 200 can also include a coating 204. The coating 204 can include any now known or later developed protective coating for the component 200, for example, exposed to hot combustion gases 220 (FIGS. 2, 5, and 7). In certain embodiments, the coating 204 is a rare earth doped zirconium oxide, cobalt-nickel-chromium-aluminum-yttrium (CoNiCrAlY), yttria stabilized zirconia (YSZ), mullite (3AL2O3·2SiO2), alumina (Al2O3), ceria (CeO2), rare earth zirconates (e.g., La2Zr2O7), rare earth oxides (e.g., La2O3, Nb2O5, Pr2O3, CeO2), metallic glass composites, and combinations thereof (e.g., alumina and YSZ or ceria and YSZ). In the case of YSZ, a certain amount of zirconium ions (Zr 4+ ) to the slightly larger yttrium ion (Y 3+ ) to obtain a stable sintered xYSZ (x represents the mol % of yttrium ions, e.g., 8YSZ). Coating 204 may also include any now known or later developed bond coating, e.g., CoNiCrAlY (not shown separately).

[0061] According to certain embodiments, during manufacture, the wall 210 and the film cooling holes 202 may be additively manufactured. Thereafter, referring to FIGS. 10 and 11, the coating 204 may be applied using any now known or later developed coating process, such as but not limited to plasma spraying. The coating 104 may be applied in a direction 290 intended to form a layer of thickness T3 on the wall exterior surface 212. As described, the hood section 270 prevents the coating 204 from filling the diffuser section 240 and / or the metering section 230, eliminating the need to individually re-drill the film cooling holes 202. According to the desired thickness T3, the coating direction 290 and the angle δ of the coating collector 246 (FIGS. 6 and 8), the distance D1 (i.e., the depth of the coating collector 246, sized by the transition 248) is identified, also taking into account the known solidification conditions of the material of the coating 204.

[0062] The transition 248 between the recess 244B of the second inner surface 244 (i.e., the coating collector 246) and either the metering section 230 (FIGS. 7 and 8) or the portion 244A of the second inner surface 244 (FIGS. 5 and 6) can take any form desired. In the examples shown in FIGS. 5-8, the contour of the transition 248 is fairly sharp, e.g., about 90°, while in FIGS. 10 and 11, the contour is more gently curved. In general, the contour of the transition 248 is positioned to provide a smooth transition between the coating 204 and the metering section 230 (FIGS. 7 or 8) or the portion 244B of the second inner surface 244 (FIGS. 5 and 6). The exact location of the inner edge 284 can be determined based on, for example, the coating direction 290, the coating application conditions, and the coating material properties.

[0063] 5 and 7, as well as the top view of FIG. 13, show the component 200 including the film cooling hole 202 with the coating 204 after the excess coating has been removed, as shown in FIG. 10 and FIG. 11. More specifically, a coating removal process, such as a polishing or grinding process, is performed to remove the excess coating 204 from over the hood section 270 (as shown in FIG. 10 and FIG. 11). After this process, the hood outer surface 276 can extend through the coating 204, as shown in FIG. 5, FIG. 7, and FIG. 13. That is, the hood outer surface 276 can be visible through the coating 204. The hood outer surface 276 can have a variety of different cross-sectional shapes as it extends through the coating 204. For example, in FIG. 13, the hood outer surface 276 is semicircular. In other embodiments, the hood outer surface 276 can be polygonal (e.g., square, rectangular, trapezoidal, etc.) or other shapes, as shown in, for example, FIG. 14-FIG. 17.

[0064] During operation, the flow of coolant from the film cooling holes 202 is quickly deflected by the diffuser section 240 into the flow direction of the hot gases 220 (FIGS. 2 and 5) so that the coolant exiting the film cooling holes 202 at the outlets 254 contacts the surface of the coating 204. The wall exterior surface 212 is covered with the coating 204. The coating collector 246 is filled with coating 204 material up to the inner edge 284, providing a cooling effect similar to that without the coating collector 246. However, the coating 204 allows coolant to be conserved and used in the hot combustion gas stream 220 (FIGS. 2, 5 and 7), which increases the cooling of the component 200 and, in the case of a gas turbine system, increases the power output.

[0065] 14-17 show cross-sectional views of a component 200 including a film cooling hole 202 according to various alternative embodiments of the present disclosure. FIG. 14 shows a film cooling hole 202 having a diffuser section 240 with a polygonal opening with a rounded upstream end. FIG. 15 shows a film cooling hole 202 having a diffuser section 240 with an elongated trapezoidal opening compared to those shown in FIGS. 5-8. FIG. 16 shows a film cooling hole 202 having a diffuser section 240 with a rectangular opening and a metering section 230 with a multi-sectional opening to the coolant source 214. FIG. 17 shows a film cooling hole 202 having a diffuser section 240 with a curved opening with a rounded upstream end and a metering section 230 with a cross-sectional curved opening to the coolant source 214 that converges slightly toward the diffuser section 240. Although various alternative embodiments of the film cooling holes 202 have been illustrated, it will be appreciated that a variety of other shapes and configurations of the components of the film cooling holes 202 may also be provided in accordance with the teachings of the present disclosure.

[0066] Embodiments of the present disclosure provide various technical and commercial advantages, examples of which are described herein: The film cooling hole including the hood section and coating collector allows the hood section to act as a shadow mask with sharp edges that reduces and in some cases prevents the coating from filling the film cooling holes, such as in the diffuser section and metering section, thus reducing manufacturing time and costs and reducing waste.

[0067] Approximate expressions used throughout the specification and claims may be applied to modify any quantitative expression that may be permissibly changed without resulting in a change in the basic function to which it relates. Thus, values ​​modified by terms such as "about", "approximately", "substantially" and the like are not limited to the exact values ​​specified. In at least some instances, approximation expressions may correspond to the precision of the instrument for measuring the value. Throughout the specification and claims, range limitations may be combined and / or interchanged. Such ranges are specified and include all subranges contained therein, unless the context or language indicates otherwise. "Approximately" or "about" applied to a particular value in a range applies to both end values ​​and may indicate ±10% of the stated value, unless dependent on the precision of the instrument for measuring the value.

[0068] Corresponding structures, materials, acts, and equivalents of all means or step-plus-function elements in the following claims are intended to include any structure, material, or act for performing a function in combination with elements recited in other claims as specifically recited in the claims. The description of the present disclosure has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the disclosure in the disclosed form. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the present disclosure. The embodiments have been chosen and described in order to best explain the principles and practical applications of the disclosure, and to enable those skilled in the art to understand the disclosure in various embodiments with various modifications suitable for the particular use contemplated. [Explanation of symbols]

[0069] 100: turbomachine 102: compressor 104: combustor 106: combustion region 108: fuel nozzle assembly 110: turbine assembly 111: turbine 112: rotor 120: nozzle row or vane row 122: stationary casing 124: rotating blades 126: stationary vanes / nozzles 128: outer platform 130: inner platform 132: rotating blades 134: inner platform 136: tip shroud 140: root 142: dovetail 144: rotor wheel 146: shank 148: platform 150: airfoil 152: pressure side (PS) outer wall 154: suction side (SS) outer wall 156: leading edge 158: trailing edge 160: outboard tip 170: outer platform 174: inner platform 76: stationary nozzle airfoil 178: Pressure side (PS) outer wall 180: Suction side (SS) outer wall 182: Leading edge 184: Trailing edge 200: Component 202: Film cooling holes 204: Coating 210: Wall 212: Wall exterior 214: Coolant source 216: Wall interior 220: Hot combustion gas flow / working fluid 230: Metering section 232: Interior 240: Diffuser section 242: First interior 244: Second interior 244A: Part 244B: Part 246: Coating collector 248: Transition 250: Opposing side 252: Opposing side 254: Outlet 262: First end 264: Edge 266: Second end 270: Hood section 272: Member 274: Hood interior 276: Hood exterior 278: Hood backside 280: Upstream edge 284: Inner edge 286: Side 286: Side wall 288: Side wall 290: Orientation

Claims

1. A turbomachine component (200), comprising: a wall (210) including an exterior wall surface (212) and an interior coolant source (214); a film cooling hole (202) disposed in a wall (210) and extending from an internal coolant source (214) to an exterior surface (212) of the wall; The film cooling holes (202) a metering section (230) in fluid communication with the internal coolant source (214); a diffuser section (240) in fluid communication with the metering section (230) and including a first inner surface (242) and a coating collector (246); a hood section (270) including a member (272) extending outwardly from the wall exterior surface (212); The turbomachine component (200), wherein the member (272) includes an inner hood surface (274) contiguous with the first inner surface (242) of the diffuser section (240) and an outer hood surface (276) parallel to the wall outer surface (212).

2. 2. The turbomachine component of claim 1, wherein the coating collector includes a portion of the second inner surface of the diffuser section that is spaced from the first inner surface, the portion of the second inner surface having a first end that intersects the wall exterior surface and forms a downstream end of the film cooling hole, and a second end that transitions to one of the metering section or another portion of the second inner surface.

3. The turbomachine component (200) of any of the preceding claims, wherein the member (272) of the hood section (270) further comprises a hood underside (278) connecting the hood exterior surface (276) and the wall exterior surface (212).

4. The turbomachine component (200) of claim 3, further comprising a coating (204) on the wall exterior surface (212), on the hood underside (278), and within the coating collector (246).

5. The turbomachine component (200) of claim 4, wherein a distance between the hood exterior surface (276) and the wall exterior surface (212) is less than or equal to a thickness of the coating (204).

6. The turbomachine component (200) of claim 4, wherein a depth of the coating collector (246) is equal to or greater than a thickness of the coating (204).

7. The turbomachine component (200) of claim 4, wherein the hood exterior surface (276) extends through the coating (204).

8. The turbomachine component (200) of any of the preceding claims, wherein the inner hood surface (274) intersects with the outer hood surface (276) forming an upstream edge (280) of the film cooling hole (202).

9. The turbomachine component (200) of any of the preceding claims, wherein the metering section (230) has a smaller cross-sectional area than the diffuser section (240).

10. 2. The turbomachine component of claim 1, wherein the diffuser section further comprises opposing sides connecting the first and second inner surfaces and diverging from one another toward an outlet of the film cooling hole.

11. The turbomachine component (200) of any of the preceding claims, wherein the hood section (270) further comprises sidewalls (286, 288) joining opposite sides of the member (272) to the wall exterior surface (212).

12. The turbomachine component (200) of any of the preceding claims, wherein the member (272) of the hood section (270) extends from the wall exterior surface (212) at an obtuse angle greater than 120° and less than 180°.

13. 2. The turbomachine component of claim 1, wherein the wall and the film cooling holes are additively manufactured, and the turbomachine component comprises an airfoil having the wall and the film cooling holes.

14. A turbomachine component (200), comprising: a wall (210) including an exterior wall surface (212) and an interior coolant source (214); a film cooling hole (202) disposed in the wall (210) and extending from an internal coolant source (214) to an exterior wall surface (212); The film cooling holes (202) a metering section (230) in fluid communication with the internal coolant source (214); a diffuser section (240) in fluid communication with the metering section (230), the diffuser section including a first inner surface (242) spaced apart from a second inner surface (244), the diffuser section including a coating collector (246), the diffuser section (240) having a larger cross-sectional area than the metering section (230); a hood section (270) including a member (272) extending outwardly from a wall exterior surface (212), the member (272) including a hood exterior surface (276) parallel to the wall exterior surface (212) and a hood underside surface (278) connecting the hood exterior surface (276) and the wall exterior surface (212); A turbomachine component (200) including a coating (204) on a wall exterior surface (212), on a hood underside (278), and within a coating collector (246), with a hood exterior surface (276) extending through the coating (204).

15. 15. The turbomachine component of claim 14, wherein the coating collector includes a portion (244B) of a second inner surface (244) of the diffuser section (240) spaced from the first inner surface (242), the portion (244B) of the second inner surface (244) including a first end (262) that intersects the wall exterior surface (212) and forms a downstream end (264) of the film cooling hole (202), and a second end (266) that transitions to one of the metering section (230) or another portion (244A) of the second inner surface (244).

Images