Turbine component and method for forming turbine component
By designing turbine components with multiple cooling channels and cooling paths, the problem of low cooling efficiency of gas turbine engine turbine components in high temperature environments is solved, and high-efficiency cooling and efficiency improvement are achieved.
Patent Information
- Application Number
- CN202411233998.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-09-06
- Filing Date
- 2024-09-04
- Publication Date
- 2025-03-07
AI Technical Summary
The turbine components of a gas turbine engine operate in high temperature environments and are difficult to cool effectively, resulting in reduced efficiency and reliability.
A turbine component is designed, including an inner platform, an outer platform and an airfoil, which has a pressure sidewall, a suction sidewall, a leading edge, a trailing edge and a plurality of cooling channels, and cooled through a plurality of cooling paths (first cooling path and a second cooling path).
Through this design, efficient cooling of turbine components is achieved, the efficiency and reliability of the engine are improved, and the consumption of cooling flow is reduced.
Smart Images
Figure CN119572312A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to a turbine component for a gas turbine engine and a method for forming the turbine component. Background Art
[0002] A gas turbine engine generally includes a compressor section, a turbine section, and a combustion section disposed between the compressor section and the turbine section. The compressor section includes multiple stages of rotating compressor blades and stationary compressor vanes. The combustion section generally includes multiple combustion chambers. The turbine section includes multiple stages of rotating turbine blades and stationary turbine vanes. The rotating turbine blades and stationary turbine vanes generally operate in a high temperature environment and require cooling. Summary of the invention
[0003] In one aspect, a turbine component is provided. The turbine component includes: an inner platform having an inner platform cooling passage; an outer platform; an airfoil extending between the inner platform and the outer platform, the airfoil having a pressure sidewall, a suction sidewall, a leading edge, a trailing edge, a leading edge region, a trailing edge region, and an intermediate region defined between the leading edge region and the trailing edge region; a leading edge rib positioned in the leading edge region and between the pressure sidewall and the suction sidewall, a plurality of leading edge rib openings formed in the leading edge rib, each leading edge rib opening being positioned closer to one of the pressure sidewall and the suction sidewall than to the other of the pressure sidewall and the suction sidewall; a trailing rib positioned in the trailing edge region and between the pressure sidewall and the suction sidewall; a first cooling path extending from a flow inlet formed in one of the inner platform and the outer platform, through the leading edge region, through the inner platform cooling passage, and into the trailing edge region; and a second cooling path extending from the flow inlet, through the intermediate region, and into the trailing edge region.
[0004] In one aspect, a method for forming a turbine component is provided. The method includes: forming an airfoil having a pressure sidewall, a suction sidewall, a leading edge and a trailing edge, a leading edge region, a trailing edge region, and an intermediate region defined between the leading edge region and the trailing edge region; positioning a leading edge rib in the leading edge region and between the pressure sidewall and the suction sidewall; forming a plurality of leading edge rib openings in the leading edge rib, each leading edge rib opening being positioned closer to one of the pressure sidewall and the suction sidewall than to the other of the pressure sidewall and the suction sidewall; positioning a trailing rib in the trailing edge region and between the pressure sidewall and the suction sidewall; forming a flow inlet in one of an inner platform and an outer platform; creating a first cooling path extending from the flow inlet through the leading edge region, through the inner platform cooling passage, and into the trailing edge region; and establishing a second cooling path extending from the flow inlet through the intermediate region and into the trailing edge region. BRIEF DESCRIPTION OF THE DRAWINGS
[0005] To easily identify the discussion of any particular element or act, the highest digit(s) in a reference number refers to the figure number in which the element is first introduced.
[0006] Figure 1 is a longitudinal cross-sectional view of a gas turbine engine taken along a plane containing the longitudinal axis or central axis.
[0007] Figure 2 Is applicable to Figure 1 A perspective view of a turbine component of a gas turbine engine.
[0008] Figure 3 yes Figure 2 A cross-sectional view of the outer platform of a turbine component.
[0009] Figure 4 yes Figure 2 Cross-sectional view of an airfoil of a turbine component.
[0010] Figure 5 yes Figure 2 Schematic cross-sectional view of a turbine component.
[0011] Figure 6 yes Figure 2 Cross-sectional view of the inner platform of a turbine component.
[0012] Figure 7 yes Figure 2 Schematic diagram of the cooling scheme of the turbine components.
[0013] Figure 8 A schematic diagram of a cooling scheme.
[0014] Fig. 9 Is has Figure 8 Cooling solution Figure 2 Schematic cross-sectional view of a turbine component.
[0015] Fig.10 Is has Figure 8 Cooling solution Figure 2 Cross-sectional view of the inner platform of a turbine component.
[0016] Fig.11 A schematic diagram of a cooling scheme.
[0017] Fig.12 Is has Fig.11 Cooling solution Figure 2 Schematic cross-sectional view of a turbine component.
[0018] Fig.13 Is has Fig.11 Cooling solution Figure 2 Cross-sectional view of the inner platform of a turbine component.
[0019] Fig.14 A schematic diagram of a cooling scheme.
[0020] Fig.15 Is has Fig.14 Cooling solution Figure 2 Schematic cross-sectional view of a turbine component.
[0021] Fig.16 Is has Fig.14 Cooling solution Figure 2 Cross-sectional view of the inner platform of a turbine component.
[0022] Fig.17 yes Figure 2 Cross-sectional view of an airfoil of a turbine component.
[0023] Fig.18 Is has Fig.17 Schematic cross-sectional view of an airfoil turbine component.
[0024] Fig.19 yes Fig.17 Schematic diagram of the cooling scheme of the turbine components.
[0025] Fig. 20 yes Fig.17 Cross-sectional view of the inner platform of a turbine component. DETAILED DESCRIPTION
[0026] Before describing in detail any embodiment of the present invention, it should be understood that the present invention is not limited in its application to the details of the structure and arrangement of the components set forth in this description or shown in the following drawings. The present invention can have other embodiments and can be practiced or performed in various ways. In addition, it should be understood that the words and terms used herein are for descriptive purposes and should not be considered as limiting.
[0027] Various techniques for systems and methods will now be described with reference to the accompanying drawings, wherein similar reference numerals represent similar elements throughout. The drawings discussed below in this patent document and the various embodiments for describing the principles of the present disclosure are intended to be illustrative only and should not be construed in any way to limit the scope of the present disclosure. It will be appreciated by those skilled in the art that the principles of the present disclosure can be implemented in any suitably arranged device. It should be understood that the functions described as being performed by certain system elements can be performed by multiple elements. Similarly, for example, an element can be configured to perform the functions described as being performed by multiple elements. Many innovative teachings of the present application will be described with reference to exemplary non-limiting embodiments.
[0028] It should be understood that, unless explicitly limited in some examples, the words or phrases used herein should be interpreted broadly. For example, the terms "include", "have" and "include" and their derivatives mean to include but not limit. Unless the context clearly indicates otherwise, the singular forms "one", "a kind of" and "the" are also intended to include plural forms. In addition, the term "and / or" used herein refers to and covers any combination and all possible combinations of one or more of the associated listed items in the associated listed items. Unless the context clearly indicates otherwise, the term "or" is inclusive, meaning and / or. The phrases "associated with..." and "associated with this" and their derivatives can mean to include, be included in, be interconnected with, include, be included in, be connected to, or be connected with, be connected to, or be connected with, be able to communicate with, cooperate with, be interlaced, be juxtaposed, be close to, be combined with, or be combined with, have, have the characteristics of, etc. Furthermore, although multiple embodiments or configurations may be described herein, any features, methods, steps, components, etc. described with respect to one embodiment may also be applicable to other embodiments without specific statement to the contrary.
[0029] Although the terms "first", "second", "third" etc. can be used in this article to refer to various elements, information, functions or actions, these elements, information, functions or actions should not be limited by these terms. On the contrary, these digital adjectives are used to distinguish different elements, information, functions or actions from each other. For example, without departing from the scope of the present disclosure, the first element, the first information, the first function or the first action can be referred to as the second element, the second information, the second function or the second action, and similarly, the second element, the second information, the second function or the second action can be referred to as the first element, the first information, the first function or the first action.
[0030] In this specification, the term "axial" or "axially" refers to a direction along the longitudinal axis of the gas turbine engine. The term "radial" or "radially" refers to a direction perpendicular to the longitudinal axis of the gas turbine engine. The term "downstream" or "rearward" refers to a direction along the flow direction. The term "upstream" or "forward" refers to a direction opposite to the flow direction.
[0031] Additionally, unless the context clearly indicates otherwise, the term "adjacent to..." may mean: one element is fairly close to another element but not in contact with the other element; or the element is in contact with another part. Furthermore, unless otherwise clearly indicated, the phrase "based on" is intended to mean "based at least in part on." The term "about" or "approximately" or similar terms are intended to encompass variations in the value of the dimension within normal industrial manufacturing tolerances. If no industry standard is available, a twenty percent variation will fall within the meaning of these terms unless otherwise indicated.
[0032] Figure 1 An example of a gas turbine engine 100 is illustrated, which includes a compressor section 102, a combustion section 104, and a turbine section 106 arranged along a central axis 112. The compressor section 102 includes a plurality of compressor stages 114, wherein each compressor stage 114 includes a set of fixed compressor vanes 116 or adjustable guide vanes and a set of rotating compressor blades 118. The rotor 134 supports the rotating compressor blades 118 to rotate about the central axis 112 during operation. In some configurations, a single integral rotor 134 extends the length of the gas turbine engine 100 and is supported for rotation by bearings at both ends. In other configurations, the rotor 134 is assembled from several separate spools attached to each other, or may include multiple disk segments attached via one bolt or multiple bolts.
[0033] The compressor section 102 is in fluid communication with an inlet section 108 to allow the gas turbine engine 100 to draw atmospheric air into the compressor section 102. During operation of the gas turbine engine 100, the compressor section 102 draws in atmospheric air and compresses the air for delivery to the combustion section 104. The illustrated compressor section 102 is an example of one compressor section 102, with other arrangements and designs being possible.
[0034] In the illustrated configuration, the combustion section 104 includes a plurality of individual combustion chambers 120, each of which operates to mix a flow of fuel with compressed air from the compressor section 102 and combust the air-fuel mixture to produce a flow of high temperature, high pressure combustion gases or exhaust gases 122. Of course, many other arrangements of the combustion section 104 are possible.
[0035] The turbine section 106 includes a plurality of turbine stages 124, wherein each turbine stage 124 includes a number of fixed turbine vanes 126 and a number of rotating turbine blades 128. The turbine stages 124 are arranged to receive exhaust gas 122 from the combustion section 104 at a turbine inlet 130 and expand the gas to convert heat and pressure energy into rotational or mechanical work. The turbine section 106 is connected to the compressor section 102 to drive the compressor section 102. For a gas turbine engine 100 used for power generation or as a prime mover, the turbine section 106 is also connected to a generator, pump, or other device to be driven. As with the compressor section 102, other designs and arrangements of the turbine section 106 are possible.
[0036] An exhaust section 110 is positioned downstream of the turbine section 106 and is arranged to receive a flow of expanded exhaust gas 122 from a final turbine stage 124 in the turbine section 106. The exhaust section 110 is arranged to effectively direct the exhaust gas 122 away from the turbine section 106 to ensure efficient operation of the turbine section 106. Many variations and design differences are possible in the exhaust section 110. Therefore, the illustrated exhaust section 110 is merely one example of such variations.
[0037] The control system 132 is coupled to the gas turbine engine 100 and operates to monitor various operating parameters and control various operations of the gas turbine engine 100. In a preferred configuration, the control system 132 is typically microprocessor-based and includes memory devices and data storage devices for collecting, analyzing, and storing data. In addition, the control system 132 provides output data to various devices including monitors, printers, indicators, etc., which allow users to interact with the control system 132 to provide input or adjustments. In the example of a power generation system, a user can input a power output set point, and the control system 132 can adjust various control inputs to achieve the power output in an efficient manner.
[0038] The control system 132 can control various operating parameters, including but not limited to variable inlet guide vane position, fuel flow rate and pressure, engine speed, valve position, generator load, and generator excitation. Of course, other applications may have fewer or more controllable devices. The control system 132 also monitors various parameters to ensure that the gas turbine engine 100 is operating properly. Some of the parameters monitored may include inlet air temperature, compressor outlet temperature and pressure, combustor outlet temperature, fuel flow rate, generator power output, bearing temperature, etc. Many of these measurements are displayed to the user and recorded for subsequent review if review is required.
[0039] Figure 2 is a perspective view of the turbine component 200, and specifically Figure 1 A perspective view of the fixed turbine vanes 126 is shown in FIG. Figure 2 The turbine component 200 in FIG. 1 illustrates a fixed turbine vane 126 , but in other configurations, the turbine component 200 may be Figure 1 The rotating turbine blades 128 are shown in FIG.
[0040] The turbine component 200 includes a platform, such as an inner platform 202 and an outer platform 204. The turbine component 200 includes an airfoil 206 disposed between the inner platform 202 and the outer platform 204. The airfoil 206 has a pressure sidewall 208 and a suction sidewall 210, which are connected at a leading edge 212 on the upstream side and a trailing edge 214 on the downstream side relative to the flow direction of a working flow 216. The working flow 216 includes Figure 1 The exhaust gas 122. The pressure side wall 208 has a generally concave shape. The suction side wall 210 has a generally convex shape. The pressure side wall 208 and the suction side wall 210 define an internal cooling space therebetween.
[0041] Each platform has a cold side and a hot side. The hot side is arranged so that the hot side forms part of the hot gas path that is in direct contact with the combustion products. The combustion products include the working flow 216. The cold side is opposite the hot side and is not in direct contact with such hot gases. Figure 2 As shown in FIG. 1 , the inner platform 202 has an inner platform cold side 218 and an inner platform hot side 220 . The outer platform 204 has an outer platform cold side 222 and an outer platform hot side 224 . The airfoil 206 is attached to the inner platform hot side 220 and the outer platform hot side 224 .
[0042] Each platform has an upstream side and a downstream side relative to the flow direction of the working stream 216. The inner platform 202 has an inner platform upstream side 226 and an inner platform downstream side 228. The outer platform 204 has an outer platform upstream side 234 and an outer platform downstream side 236.
[0043] Each platform has a suction side mating surface and a pressure side mating surface. Figure 1 Each of the inner and outer platforms is generally adjacent to another turbine component 200 in the circumferential direction around the rotor 134. The inner platform 202 has an inner platform suction side mating surface 232 and an inner platform pressure side mating surface 230. The outer platform 204 has an outer platform pressure side mating surface 238 and an outer platform suction side mating surface 240.
[0044] The outer platform 204 includes a pressure side impingement plate 242 and a suction side impingement plate 244 disposed at the outer platform cold side portion 222. The pressure side impingement plate 242 is disposed adjacent to the pressure side wall 208 and extends from the leading edge 212 toward the trailing edge 214. The suction side impingement plate 244 is disposed adjacent to the suction side wall 210 and extends from the leading edge 212 toward the trailing edge 214. The outer platform 204 has a pressure side impingement pocket 302 (e.g., Figure 3 ) and the suction side impact pocket 304 covered by the suction side impact plate 244 (as shown in Figure 3 ). The pressure side impingement plate 242 and the suction side impingement plate 244 define a plurality of impingement cooling holes to provide a cooling flow 246 into the pressure side impingement pocket 302 and the suction side impingement pocket 304. The cooling flow 246 includes compressed air from the compressor section 102, wherein other types of cooling flows are possible.
[0045] The shroud 248 is coupled to the outer platform 204. The shroud 248 is disposed along the internal cooling space and has an opening in fluid communication with the internal cooling space. The shroud 248 covers the internal cooling space from the trailing edge 214 toward the leading edge 212. In other configurations, the shroud 248 may cover the internal cooling space at any desired section from the leading edge 212 to the trailing edge 214. It should also be understood that the shroud 248 may be coupled to the inner platform 202 along the internal cooling space and have an opening in fluid communication with the internal cooling space.
[0046] Figure 3 2 is a cross-sectional view of the outer platform 204. The outer platform 204 includes an outer platform cooling passage 314, which has an outer platform pressure side cooling passage 306 and an outer platform suction side cooling passage 308. The outer platform pressure side cooling passage 306 is formed between the outer platform upstream side 234 and the outer platform downstream side 236 and is located in the pressure side of the outer platform 204. The pressure side impingement pocket 302 retains the cooling flow 246 that passes through the impingement cooling holes of the pressure side impingement plate 242. The cooling flow 246 in the pressure side impingement pocket 302 flows through the outer platform pressure side cooling passage 306 and leaves the outer platform 204 through a plurality of outer platform pressure side outlet holes 310. The plurality of outer platform pressure side outlet holes 310 are positioned along the outer platform pressure side mating surface 238. The outer platform pressure side cooling passage 306 is a serpentine flow path. As used herein, the term "serpentine flow path" refers to a flow path that includes at least one turn greater than 45 degrees.
[0047] The outer platform suction side cooling passage 308 is formed between the outer platform upstream side 234 and the outer platform downstream side 236 and is located within the suction side of the outer platform 204. The suction side impingement pocket 304 retains the cooling flow 246 that passes through the impingement cooling holes of the suction side impingement plate 244. The cooling flow 246 in the suction side impingement pocket 304 flows through the outer platform suction side cooling passage 308 and exits the outer platform 204 through the plurality of outer platform suction side outlet holes 312. The plurality of outer platform suction side outlet holes 312 are located along the outer platform downstream side 236 and the outer platform pressure side mating surface 238.
[0048] Figure 4 2 is a cross-sectional view of the airfoil 206. The airfoil 206 has a front rib 402 and a rear rib 404 positioned between the pressure side wall 208 and the suction side wall 210. The airfoil 206 has a leading edge region 406 arranged on the leading edge side, a trailing edge region 410 arranged on the trailing edge side, and an intermediate region 408 arranged between the leading edge region 406 and the trailing edge region 410. Figure 4 In the embodiment illustrated in FIG. 2 , the leading edge region 406 is defined between the leading edge 212 and the leading rib 402. The intermediate region 408 is defined between the leading rib 402 and the trailing rib 404. The trailing edge region 410 is defined between the trailing rib 404 and the trailing edge 214.
[0049] The leading edge rib 412 is positioned between the pressure side wall 208 and the suction side wall 210 and within the leading edge region 406. The leading edge rib 412 divides the leading edge region 406 into a first leading edge cooling channel 414 and a second leading edge cooling channel 416. The first leading edge cooling channel 414 is defined between the leading edge rib 402 and the leading edge rib 412. The second leading edge cooling channel 416 is defined between the leading edge rib 412 and the leading edge 212. A plurality of leading edge rib openings 424 are formed in the leading edge rib 412, and these leading edge rib openings 424 are distributed along the leading edge rib 412 between the inner platform 202 and the outer platform 204. The plurality of leading edge rib openings 424 are positioned closer to one of the pressure side wall 208 and the suction side wall 210 than to the other of the pressure side wall 208 and the suction side wall 210. In Figure 4 In the embodiment illustrated in , the plurality of leading edge rib openings 424 are positioned closer to the suction side wall 210 than to the pressure side wall 208. In other configurations, the plurality of leading edge rib openings 424 may be positioned closer to the pressure side wall 208 than to the suction side wall 210, or a portion of the leading edge rib openings 424 may be positioned closer to the suction side wall 210 than to the pressure side wall 208, while the remainder of the leading edge rib openings 424 may be positioned closer to the pressure side wall 208 than to the suction side wall 210. Figure 4In the embodiment illustrated in FIG. 5 , the distribution and size of the leading edge rib openings 424 are equal in the flow direction of the first cooling flow 506. In other embodiments, the distribution and size of the leading edge rib openings 424 may vary in the flow direction based on design requirements. For example, the size of the leading edge rib openings 424 may be smaller at the start of the second leading edge cooling channel 416 and widen toward the end of the second leading edge cooling channel 416.
[0050] The middle rib 418 is positioned between the pressure side wall 208 and the suction side wall 210 and within the middle region 408. The middle rib 418 divides the middle region 408 into a first middle cooling passage 420 and a second middle cooling passage 422. The first middle cooling passage 420 is defined between the front rib 402 and the middle rib 418. The second middle cooling passage 422 is defined between the middle rib 418 and the rear rib 404. The first displacement body 426 is inserted into the first middle cooling passage 420 to form a first near-wall cooling passage between the first displacement body 426 and the pressure side wall 208, the suction side wall 210, the front rib 402, and the middle rib 418. The second displacement body 426 is inserted into the second middle cooling passage 422 to form a second near-wall cooling passage between the second displacement body 426 and the pressure side wall 208, the suction side wall 210, the middle rib 418, and the rear rib 404. The first displacement body 426 and the second displacement body 426 may be solid or hollow inside. The first displacement body 426 and the second displacement body 426 are coupled to the pressure side wall 208 and the suction side wall 210 through fastening elements.
[0051] The trailing edge rib 428 is positioned between the pressure side wall 208 and the suction side wall 210 and within the trailing edge region 410. The trailing edge rib 428 divides the trailing edge region 410 into a first trailing edge cooling passage 430 and a second trailing edge cooling passage 432. The first trailing edge cooling passage 430 is defined between the trailing rib 404 and the trailing edge rib 428. The second trailing edge cooling passage 432 is defined between the trailing edge rib 428 and the trailing edge 214. A plurality of pin fins 436 are positioned within the second trailing edge cooling passage 432. A plurality of trailing edge exit holes 434 are formed in the trailing edge 214 and are distributed along the trailing edge 214 between the inner platform 202 and the outer platform 204.
[0052] Figure 5 2 is a schematic cross-sectional view of turbine component 200. A plurality of front rib openings 502 are formed in front rib 402 and distributed along front rib 402 between inner platform 202 and outer platform 204. In other configurations, front rib 402 may be a solid rib without front rib openings 502.
[0053] A first inlet 504 is formed in one of the inner platform 202 and the outer platform 204 to receive a first cooling flow 506 into the first leading edge cooling passage 414. Figure 5 , the first inlet 504 is formed in the outer platform 204. In other embodiments, the first inlet 504 may be formed in the inner platform 202. The first leading edge cooling passage 414 extends between the leading edge ribs 402 and the leading edge ribs 412, and between the outer platform 204 and the inner platform 202. The second leading edge cooling passage 416 extends between the leading edge ribs 412 and the leading edge 212, and between the outer platform 204 and the inner platform 202. The leading edge ribs 412 are positioned within the leading edge region 406 so that the first leading edge cooling passage 414 is a converging flow passage and the second leading edge cooling passage 416 is a diverging flow passage for the first cooling flow 506. A leading edge flow connection 512 is formed between the leading edge region 406 and the inner platform 202 to direct the first cooling flow 506 from the leading edge region 406 to the inner platform cooling passage 614 formed in the inner platform 202. Leading edge flow connection 512 is the only flow outlet for leading edge region 406. First cooling flow 506 may be cooling flow 246 including compressed air from compressor section 102, wherein other types of cooling flows are possible.
[0054] A second inlet 508 is formed in one of the inner platform 202 and the outer platform 204 to receive the second cooling flow 510 into the first intermediate cooling passage 420. Figure 5 , the second inlet 508 is formed in the outer platform 204. In other embodiments, the second inlet 508 may be formed in the inner platform 202. The first intermediate cooling passage 420 extends between the forward rib 402 and the intermediate rib 418, and between the outer platform 204 and the inner platform 202. The second intermediate cooling passage 422 extends between the intermediate rib 418 and the aft rib 404, and between the inner platform 202 and the outer platform 204. The second cooling flow 510 may be a cooling flow 246 including compressed air from the compressor section 102, wherein other types of cooling flows are also possible.
[0055] The first shroud 248 is coupled to the inner platform 202 at the inner platform cold side 218. A first connecting flow channel 516 is formed in the first shroud 248 in the inner platform 202. The first connecting flow channel 516 connects the first intermediate cooling channel 420 with the second intermediate cooling channel 422 and reverses the flow direction of the second cooling flow 510. The second shroud 248 is coupled to the outer platform 204 at the outer platform cold side 222. A second connecting flow channel 518 is formed in the second shroud 248 in the outer platform 204. The second connecting flow channel 518 connects the second intermediate cooling channel 422 with the trailing edge region 410 and reverses the flow direction of the second cooling flow 510. In other configurations, only one of the inner platform 202 and the outer platform 204 is coupled to the shroud 248. In these embodiments, one of the first connecting flow passage 516 and the second connecting flow passage 518 is formed outside the airfoil 206, and the other of the first connecting flow passage 516 and the second connecting flow passage 518 is formed inside the airfoil 206. It is also possible that both the inner platform 202 and the outer platform 204 are not coupled to the shroud 248. In such embodiments, both the first connecting flow passage 516 and the second connecting flow passage 518 are formed inside the airfoil 206.
[0056] The first trailing edge cooling passage 430 extends between the trailing rib 404 and the trailing edge rib 428, and extends between the outer platform 204 and the inner platform 202. The second trailing edge cooling passage 432 extends between the trailing edge rib 428 and the trailing edge 214, and extends between the inner platform 202 and the outer platform 204. The trailing edge rib 428 is positioned within the trailing edge region 410 so that the first trailing edge cooling passage 430 is a converging flow passage for the second cooling flow 510, and the second trailing edge cooling passage 432 is a converging flow passage for the first cooling flow 506. A trailing edge flow connection 520 is formed between the inner platform cooling passage 614 and the trailing edge region 410 to direct the first cooling flow 506 from the inner platform cooling passage 614 into the trailing edge region 410. Figure 5 In the embodiment illustrated in , the trailing edge flow connection 520 is positioned between the trailing edge rib 428 and the trailing edge 214 to direct the first cooling flow 506 into the second trailing edge cooling channel 432. In other configurations, the trailing edge flow connection 520 may be positioned between the trailing edge rib 404 and the trailing edge rib 428, or positioned at any desired location.
[0057] A plurality of trailing edge rib openings 514 are formed in the trailing edge rib 428 and distributed along the trailing edge rib 428 between the inner platform 202 and the outer platform 204. Each trailing edge rib opening 514 defines a dimension that increases in the flow direction of the first trailing edge cooling passage 430.
[0058] A plurality of pin fins 436 are positioned in the second trailing edge cooling passage 432. The plurality of pin fins 436 are arranged in an array including rows between the inner platform 202 and the outer platform 204 and columns between the trailing edge ribs 428 and the trailing edge 214. The first cooling flow 506 and the second cooling flow 510 bypass the pin fins 436 and exit the turbine component 200 through the plurality of trailing edge exit holes 434.
[0059] Figure 6 2 is a cross-sectional view of the inner platform 202. The inner platform 202 includes a pressure side pocket 602 disposed on the upstream side along the pressure side wall 208. The inner platform 202 includes a suction side pocket 604 disposed on the upstream side along the suction side wall 210.
[0060] The inner platform 202 includes an inner platform cooling passage 614 having an inner platform pressure side cooling passage 606 and an inner platform suction side cooling passage 608. The inner platform pressure side cooling passage 606 is formed between the inner platform upstream side 226 and the inner platform downstream side 228 and is located within the pressure side of the inner platform 202. The pressure side pocket 602 receives a first portion of the first cooling flow 506 from the leading edge region 406. The first portion of the first cooling flow 506 then flows into the inner platform pressure side cooling passage 606. A portion of the first portion of the first cooling flow 506 enters the trailing edge region 410 via the trailing edge flow connection 520. The trailing edge flow connection 520 is positioned between the inner platform pressure side cooling passage 606 and the trailing edge region 410. In other configurations, the trailing edge flow connection 520 may be positioned between the inner platform suction side cooling passage 608 and the trailing edge region 410, or between the inner platform pressure side cooling passage 606 and the trailing edge region 410 and between the inner platform suction side cooling passage 608 and the trailing edge region 410. The remainder of the first portion of the first cooling flow 506 flows through the serpentine flow path and exits the turbine component 200 through a plurality of inner platform pressure side outlet holes 610 positioned along the inner platform pressure side mating surface 230. In other configurations, the entire first portion of the first cooling flow 506 may enter the trailing edge region 410 through the trailing edge flow connection 520 or other trailing edge flow connections. The trailing edge flow connection 520 may be formed by machining or any suitable method.
[0061] The inner platform suction side cooling passage 608 is formed between the inner platform upstream side 226 and the inner platform downstream side 228 and is located within the suction side of the inner platform 202. The suction side pocket 604 receives the second portion of the first cooling flow 506 from the leading edge region 406. The second portion of the first cooling flow 506 then flows into the inner platform suction side cooling passage 608 and exits the inner platform 202 through a plurality of inner platform suction side exit holes 612 located along the inner platform downstream side 228 and the inner platform suction side mating surface 232. In other configurations, at least a portion of the second portion of the first cooling flow 506 may enter the trailing edge region 410 through other trailing edge flow connections.
[0062] Figure 7 is a schematic diagram of a cooling scheme 700 for a turbine component 200. The cooling scheme 700 includes a first cooling path 702 extending from a first inlet 504 through a leading edge region 406, through an inner platform cooling passage 614, and into a trailing edge region 410. A first cooling flow 506 enters the first cooling path 702 from the first inlet 504 and flows into the first leading edge cooling passage 414. Then, the first cooling flow 506 flows into the second leading edge cooling passage 416 through a plurality of leading edge rib openings 424 while passing through the first leading edge cooling passage 414. Then, the entire first cooling flow 506 enters the inner platform cooling passage 614 through a leading edge flow connection 512. The leading edge flow connection 512 is the only flow outlet of the first cooling flow 506 in the leading edge region 406. A first portion of the first cooling flow 506 enters the inner platform pressure side cooling passage 606 to cool the inner platform 202, and then flows into the second trailing edge cooling passage 432 through the trailing edge flow connection 520, while a portion of the first portion of the first cooling flow 506 exits the turbine component 200 through the plurality of inner platform pressure side outlet holes 610. A second portion of the first cooling flow 506 enters the inner platform suction side cooling passage 608 to cool the inner platform 202, and then exits the turbine component 200 through the plurality of inner platform suction side outlet holes 612.
[0063] The cooling scheme 700 includes a second cooling path 704 extending from the second inlet 508 through the middle region 408 and into the trailing edge region 410. The second cooling flow 510 enters the second cooling path 704 from the second inlet 508 and flows into the first intermediate cooling channel 420. Then, the second cooling flow 510 flows through a serpentine cooling path formed by the first intermediate cooling channel 420, the first connecting flow channel 516, the second intermediate cooling channel 422, the second connecting flow channel 518, and the first trailing edge cooling channel 430. The flow direction of the second cooling flow 510 is reversed by the first connecting flow channel 516 and reversed again by the second connecting flow channel 518. A portion of the second cooling flow 510 enters the first leading edge cooling channel 414 through the plurality of leading rib openings 502 and merges with the first cooling flow 506 in the first cooling path 702. In other configurations, the forward rib 402 may be a solid rib without the forward rib opening 502 , such that the entire second cooling flow 510 flows through the second cooling path 704 .
[0064] The second cooling flow 510 in the first trailing edge cooling passage 430 flows into the second trailing edge cooling passage 432 through the plurality of trailing edge rib openings 514 and mixes with the first cooling flow 506 in the second trailing edge cooling passage 432. The first cooling flow 506 and the second cooling flow 510 flow around the plurality of pin fins 436 (eg, Figure 5 ) and exits turbine component 200 through a plurality of trailing edge exit holes 434.
[0065] Figure 8 is a schematic diagram of cooling scheme 800 . Fig. 9 is a schematic cross-sectional view of turbine component 200 having a cooling scheme 800 . Fig.10 is a cross-sectional view of the inner platform 202 with the cooling scheme 800 .
[0066] In the cooling scheme 800, the trailing edge flow connection 520 is positioned between the inner platform suction side cooling channel 608 and the trailing edge region 410. The entire first cooling flow 506 in the first cooling path 702 enters the inner platform suction side cooling channel 608 to cool the inner platform 202. Then, the entire first cooling flow 506 flows into the second trailing edge cooling channel 432 through the trailing edge flow connection 520, while a portion of the entire first cooling flow 506 leaves the turbine component 200 through the plurality of inner platform suction side outlet holes 612.
[0067] The second cooling flow 510 in the second cooling path 704 is divided into a first portion and a second portion. The first portion of the second cooling flow 510 flows through a serpentine cooling path formed by the first intermediate cooling passage 420, the first connecting flow passage 516, the second intermediate cooling passage 422, the second connecting flow passage 518, and the first trailing edge cooling passage 430. A portion of the second portion of the second cooling flow 510 enters the inner platform pressure side cooling passage 606 from the first intermediate cooling passage 420 to cool the inner platform 202, and then exits the turbine component 200 through a plurality of inner platform pressure side outlet holes 610. The inner platform cooling passage 614 includes an inner platform leading edge cooling passage 1002 formed between the inner platform upstream side 226 and the leading edge region 406. The remaining portion of the second portion of the second cooling flow 510 enters the inner platform leading edge cooling passage 1002 to cool the inner platform 202, and then exits the turbine component 200 through a plurality of inner platform leading edge outlet holes 1004 located along the inner platform upstream side 226.
[0068] The front rib 402 is a solid rib without the front rib opening 502. The entire second cooling flow 510 flows through the second cooling path 704. In other configurations, the front rib 402 may have a plurality of front rib openings 502, and a portion of the second cooling flow 510 enters the first leading edge cooling channel 414 through the plurality of front rib openings 502 and merges with the first cooling flow 506 in the first cooling path 702, as shown in FIG. Figure 5 and Figure 7 As shown in the figure.
[0069] Cooling scheme 800 otherwise has a similar configuration as cooling scheme 700 .
[0070] Fig.11 is a schematic diagram of cooling scheme 1100 . Fig.12 is a schematic cross-sectional view of a turbine component 200 having a cooling scheme 1100 . Fig.13 is a cross-sectional view of the inner platform 202 with the cooling scheme 1100 .
[0071] In the cooling scheme 1100, the first cooling flow 506 in the first cooling path 702 is divided into a first portion and a second portion. The first portion of the first cooling flow 506 flows from the first leading edge cooling channel 414 into the second leading edge cooling channel 416, and then enters the inner platform suction side cooling channel 608. Then, the first portion of the first cooling flow 506 flows into the second trailing edge cooling channel 432, while a portion of the first portion of the first cooling flow 506 leaves the turbine component 200 through a plurality of inner platform suction side outlet holes 612. The second portion of the first cooling flow 506 in the first leading edge cooling channel 414 is divided into two other portions. The first other portion of the second portion of the first cooling flow 506 enters the inner platform pressure side cooling channel 606 to cool the inner platform 202, and then leaves the turbine component 200 through a plurality of inner platform pressure side outlet holes 610. The second other portion of the second portion of the first cooling flow 506 enters the inner platform leading edge cooling channel 1002 to cool the inner platform 202, and then leaves the turbine component 200 through a plurality of inner platform leading edge outlet holes 1004.
[0072] The front rib 402 is a solid rib without the front rib opening 502. The entire second cooling flow 510 flows through the second cooling path 704. In other configurations, the front rib 402 may have a plurality of front rib openings 502, and a portion of the second cooling flow 510 enters the first leading edge cooling channel 414 through the plurality of front rib openings 502 and merges with the first cooling flow 506 in the first cooling path 702, as shown in FIG. Figure 5 and Figure 7 As shown in the figure.
[0073] Cooling scheme 1100 otherwise has a similar configuration as cooling scheme 700 .
[0074] Fig.14 is a schematic diagram of cooling scheme 1400 . Fig.15 is a schematic cross-sectional view of a turbine component 200 having a cooling scheme 1400 . Fig.16 is a cross-sectional view of the inner platform 202 with the cooling scheme 1400 .
[0075] In the cooling scheme 1400, the first cooling flow 506 in the first cooling path 702 is divided into a first portion and a second portion. The first portion of the first cooling flow 506 flows from the first leading edge cooling channel 414 into the second leading edge cooling channel 416, and then enters the inner platform suction side cooling channel 608. Then, the first portion of the first cooling flow 506 flows into the second trailing edge cooling channel 432, while a portion of the first portion of the first cooling flow 506 leaves the turbine component 200 through the plurality of inner platform suction side outlet holes 612. The second portion of the first cooling flow 506 flows from the first leading edge cooling channel 414 into the inner platform leading edge cooling channel 1002 to cool the inner platform 202, and then leaves the turbine component 200 through the plurality of inner platform leading edge outlet holes 1004.
[0076] The second cooling flow 510 in the second cooling path 704 is divided into a first portion and a second portion. The first portion of the second cooling flow 510 flows through a serpentine cooling path formed by the first intermediate cooling passage 420, the first connecting flow passage 516, the second intermediate cooling passage 422, the second connecting flow passage 518, and the first trailing edge cooling passage 430. The second portion of the second cooling flow 510 flows from the first intermediate cooling passage 420 into the inner platform pressure side cooling passage 606 to cool the inner platform 202, and then exits the turbine component 200 through the plurality of inner platform pressure side outlet holes 610.
[0077] The front rib 402 is a solid rib without the front rib opening 502. The entire second cooling flow 510 flows through the second cooling path 704. In other configurations, the front rib 402 may have a plurality of front rib openings 502, and a portion of the second cooling flow 510 enters the first leading edge cooling channel 414 through the plurality of front rib openings 502 and merges with the first cooling flow 506 in the first cooling path 702, as shown in FIG. Figure 5 and Figure 7 As shown in the figure.
[0078] Cooling scheme 1400 otherwise has a similar configuration as cooling scheme 700 .
[0079] Fig.17 is a cross-sectional view of an airfoil 1700 of a turbine component 200. Fig.17 , the leading rib 402 is removed in the airfoil 1700. The leading edge region 406 is defined between the leading edge 212 and the leading edge rib 412, and the leading edge rib 412 defines the leading edge cooling channel 1702. The leading edge cooling channel 1702 is a diverging flow channel for the first cooling flow 506. The intermediate region 408 is defined between the leading edge rib 412 and the rear rib 404. The first intermediate cooling channel 420 is defined between the leading edge rib 412 and the intermediate rib 418. The trailing edge region 410 is defined between the rear rib 404 and the trailing edge 214.
[0080] Airfoil 1700 otherwise has a similar configuration as airfoil 206 .
[0081] Fig.18 is a schematic cross-sectional view of a turbine component 200 having an airfoil 1700 . Fig.19 yes Fig.17 1900 is an illustrative cooling scheme for turbine component 200 . Fig. 20 yes Fig.17 FIG. 2 is a cross-sectional view of an inner platform 202 of a turbine component 200 .
[0082] In the cooling scheme 1900, the first inlet 504 and the second inlet 508 are combined into a flow inlet 1802 formed in one of the inner platform 202 and the outer platform 204. Fig.18 , the flow inlet 1802 is formed in the outer platform 204. In other embodiments, the flow inlet 1802 may be formed in the inner platform 202. The first cooling flow 506 is supplied into the first cooling path 702 through the flow inlet 1802, and enters the leading edge cooling channel 1702 through the plurality of leading edge rib openings 424 while passing through the first intermediate cooling channel 420. Then, the entire first cooling flow 506 enters the inner platform suction side cooling channel 608 through the leading edge flow connection 512, and then enters the second trailing edge cooling channel 432 through the trailing edge flow connection 520.
[0083] The second cooling flow 510 is supplied into the second cooling path 704 through the flow inlet 1802 and enters the first intermediate cooling passage 420, and then is divided into a first portion and a second portion. The first portion of the second cooling flow 510 flows through the serpentine cooling path formed by the first intermediate cooling passage 420, the first connecting flow passage 516, the second intermediate cooling passage 422, the second connecting flow passage 518, and the first trailing edge cooling passage 430. A portion of the second portion of the second cooling flow 510 enters the inner platform pressure side cooling passage 606 from the first intermediate cooling passage 420 to cool the inner platform 202, and then leaves the turbine component 200 through the plurality of inner platform pressure side outlet holes 610. The remaining portion of the second portion of the second cooling flow 510 enters the inner platform leading edge cooling passage 1002 to cool the inner platform 202, and then leaves the turbine component 200 through the plurality of inner platform leading edge outlet holes 1004.
[0084] Cooling scheme 1900 otherwise has a similar configuration to cooling scheme 700 .
[0085] During operation, the first cooling flow 506 is supplied into the first cooling path 702 through the first inlet 504 and enters the first leading edge cooling channel 414, and then enters the second leading edge cooling channel 416 through the plurality of leading edge rib openings 424. The first cooling flow 506 may also be supplied into the first cooling path 702 through the flow inlet 1802 and enter the leading edge cooling channel 1702 through the plurality of leading edge rib openings 424. The leading edge rib openings 424 generate the first cooling flow 506 in the second leading edge cooling channel 416 or in the leading edge cooling channel 1702, and the first cooling flow 506 is a swirl flow. A swirl flow refers to a turbulent vortex flow that may have a spiral, spiral, or suitable flow path. The swirling first cooling flow 506 cools the leading edge 212 in a swirling manner. The distribution and size of the leading edge rib openings 424 can be equal or varied in the flow direction of the swirling first cooling flow 506 so as to maximize the flow turbulence and heat transfer in the flow direction while maintaining sufficient static pressure on the rear side of the leading edge 212. The converging first leading edge cooling channel 414 and the diverging second leading edge cooling channel 416 or the diverging leading edge cooling channel 1702 ensure uniform flow distribution of the first cooling flow 506 when entering the second leading edge cooling channel 416 or the leading edge cooling channel 1702 in the flow direction. The entire first cooling flow 506 leaves the leading edge region 406 and enters the inner platform cooling channel 614 through the leading edge flow connection 512 to cool the inner platform 202. Then, at least a portion of the first cooling flow 506 flows back to the airfoil 206 through the trailing edge flow connection 520 to cool the airfoil 206.
[0086] The second cooling flow 510 is supplied into the second cooling path 704 through the second inlet 508 or through the flow inlet 1802. The second cooling flow 510 flows through a serpentine cooling path consisting of the first intermediate cooling channel 420, the first connecting flow channel 516, the second intermediate cooling channel 422, the second connecting flow channel 518, and the first trailing edge cooling channel 430. At least one of the first connecting flow channel 516 and the second connecting flow channel 518 is formed outside the airfoil 206 in one of the inner platform 202 and the outer platform 204. The displacement body 426 makes the first intermediate cooling channel 420 and the second intermediate cooling channel 422 close to the wall cooling channel. The converging first trailing edge cooling channel 430 for the second cooling flow 510 and the increasing size of the trailing edge rib opening 514 in the flow direction ensure uniform flow distribution of the second cooling flow 510 when entering the second trailing edge cooling channel 432 along the first trailing edge cooling channel 430. The first cooling flow 506 and the second cooling flow 510 flow around the plurality of pin fins 436 and exit the turbine component 200 through the plurality of trailing edge exit holes 434 .
[0087] The swirling cooling of the leading edge 212 effectively cools the leading edge 212. The film cooling holes at the leading edge 212 can be eliminated. Therefore, the aerodynamic losses caused by the boundary layer disturbance around the airfoil 206 caused by the blown film cooling flow can be eliminated. The entire first cooling flow 506 flows into the inner platform cooling channel 614 after cooling the leading edge area 406. A portion of the first cooling flow 506 flows back to the airfoil 206 after cooling the inner platform 202. The second cooling flow 510 can flow out of the airfoil 206, enter at least one of the inner platform 202 and the outer platform 204, and be deflected by the cover 248 and turned back into the airfoil 206. This arrangement cools the entire height of the airfoil 206 from the inner platform 202 to the outer platform 204. The displacement body 426 positioned in the first intermediate cooling channel 420 and the second intermediate cooling channel 422 forms a near-wall cooling channel in the middle area 408. The near-wall cooling channel effectively cools the turbine component 200. The plurality of pin fins 436 also improves cooling efficiency. The cooling scheme 700 is a highly efficient and closed-loop cooling scheme and reduces the consumption of cooling flow. Therefore, the efficiency of the gas turbine engine 100 is improved.
[0088] Although the exemplary embodiments of the present disclosure have been described in detail, those skilled in the art will understand that various changes, substitutions, variations, and improvements may be made to what is disclosed herein without departing from the spirit and scope of the disclosure in its broadest form.
[0089] Nothing in this application should be read as implying that any particular element, step, act, or function is essential to be included in the scope of the claims. The scope of patented subject matter is limited only by the claims that allow. Furthermore, unless the exact words "means for..." are followed by a participle, none of the claims are intended to invoke a means-plus-function claim structure.
Claims
1. A turbine component, comprising: An inner platform, wherein the inner platform has an inner platform cooling channel; External platform; an airfoil extending between the inner platform and the outer platform, the airfoil having a pressure sidewall, a suction sidewall, a leading edge, a trailing edge, a leading edge region, a trailing edge region, and an intermediate region defined between the leading edge region and the trailing edge region; a leading edge rib positioned in the leading edge region and between the pressure side wall and the suction side wall, the leading edge rib having a plurality of leading edge rib openings formed therein, each leading edge rib opening being positioned closer to one of the pressure side wall and the suction side wall than to the other of the pressure side wall and the suction side wall; an aft rib positioned in the trailing edge region and between the pressure side wall and the suction side wall; a first cooling path extending from a flow inlet formed in one of the inner platform and the outer platform, through the leading edge region, through the inner platform cooling passage, and into the trailing edge region; as well as A second cooling path extends from the flow inlet, through the intermediate region, and into the trailing edge region.
2. The turbine component according to claim 1, in, A leading edge cooling channel is defined between the leading edge rib and the leading edge, and wherein the leading edge cooling channel is a diverging flow channel.
3. The turbine component according to claim 1, further comprising: a forward rib positioned in the leading edge region and between the pressure side wall and the suction side wall; a first leading edge cooling passage, the first leading edge cooling passage being defined between the leading edge rib and the leading rib; as well as a second leading edge cooling passage, the second leading edge cooling passage being defined between the leading edge rib and the leading edge, Wherein, the first leading edge cooling channel is a converging flow channel, and Wherein, the second leading edge cooling channel is a divergent flow channel.
4. The turbine component according to claim 1, further comprising: a trailing edge rib positioned in the trailing edge region and between the pressure side wall and the suction side wall; a first trailing edge cooling passage defined between the trailing edge rib and the rear rib; a second trailing edge cooling passage, the second trailing edge cooling passage being defined between the trailing edge rib and the trailing edge, Wherein, the first trailing edge cooling channel is a converging flow channel, and Wherein, the second trailing edge cooling channel is a converging flow channel.
5. The turbine component according to claim 4, further comprising: a plurality of trailing edge rib openings formed in the trailing edge rib, Wherein, the size of each trailing edge rib opening increases along the flow direction of the first trailing edge cooling channel.
6. The turbine component according to claim 4, further comprising: A trailing edge flow connection is formed between the inner platform cooling passage and the trailing edge region.
7. The turbine component according to claim 6, in, The trailing edge flow connection is positioned between the trailing edge rib and the trailing edge.
8. The turbine component of claim 1, further comprising: a leading edge flow connection formed between the leading edge region and the inner platform cooling passage, The leading edge flow connection portion is the only flow outlet of the leading edge region.
9. The turbine component of claim 1, further comprising: a shroud coupled to one of the inner platform and the outer platform, Wherein the shroud is positioned to reverse a flow direction of a cooling flow in the second cooling path.
10. The turbine component of claim 1, further comprising: A displacement body is positioned in the intermediate area.
11. A method for forming a turbine component, the method comprising: forming an airfoil having a pressure sidewall, a suction sidewall, a leading edge and a trailing edge, a leading edge region, a trailing edge region, and an intermediate region defined between the leading edge region and the trailing edge region; positioning a leading edge rib in the leading edge region between the pressure side wall and the suction side wall; forming a plurality of leading edge rib openings in the leading edge rib, each leading edge rib opening being positioned closer to one of the pressure side wall and the suction side wall than to the other of the pressure side wall and the suction side wall; positioning a trailing rib in the trailing edge region between the pressure side wall and the suction side wall; forming a flow inlet in one of the inner platform and the outer platform; creating a first cooling path extending from the flow inlet, through the leading edge region, through an inner platform cooling passage, and into the trailing edge region; as well as A second cooling path is established extending from the flow inlet, through the intermediate region and into the trailing edge region.
12. The method according to claim 11, further comprising: positioning a trailing edge rib in the trailing edge region between the pressure side wall and the suction side wall; forming a first trailing edge cooling passage defined between the trailing edge rib and the rear rib; as well as forming a second trailing edge cooling passage defined between the trailing edge rib and the trailing edge, wherein the second cooling path extends from the middle region into the first trailing edge cooling channel, Wherein, the first trailing edge cooling channel is a converging flow channel, and Wherein, the second trailing edge cooling channel is a converging flow channel.
13. The method according to claim 12, further comprising: forming a plurality of trailing edge rib openings in the trailing edge rib, wherein the second cooling path extends from the first trailing edge cooling channel through the plurality of trailing edge rib openings into the second trailing edge cooling channel, Wherein, the size of each trailing edge rib opening increases along the flow direction of the first trailing edge cooling channel.
14. The method according to claim 12, further comprising: positioning a forward rib in the leading edge region between the pressure side wall and the suction side wall; forming a first leading edge cooling passage defined between the leading edge rib and the leading rib; as well as forming a second leading edge cooling passage defined between the leading edge and the leading edge rib, wherein the first cooling path extends from the flow inlet into the first leading edge cooling channel and extends through the plurality of leading edge rib openings into the second leading edge cooling channel, Wherein, the first leading edge cooling channel is a converging flow channel, and Wherein, the second leading edge cooling channel is a divergent flow channel.
15. The method according to claim 14, in, The first cooling path extends from the second leading edge cooling channel into the inner platform pressure side cooling channel and into the second trailing edge cooling channel, and from the second leading edge cooling channel into the inner platform suction side cooling channel.
16. The method according to claim 14, further comprising: positioning an intermediate rib in the intermediate region between the pressure side wall and the suction side wall; as well as forming a first intermediate cooling channel defined between the front rib and the intermediate rib, wherein the first cooling path extends from the second leading edge cooling channel to the inner platform suction side cooling channel and to the second trailing edge cooling channel, and The second cooling path extends from the first intermediate cooling channel to the inner platform pressure side cooling channel and the inner platform leading edge cooling channel.
17. The method according to claim 14, in, The first cooling path extends from the first leading edge cooling channel into an inner platform pressure side cooling channel and an inner platform leading edge cooling channel, and from the second leading edge cooling channel into an inner platform suction side cooling channel and into the second trailing edge cooling channel.
18. The method according to claim 14, further comprising: positioning an intermediate rib in the intermediate region between the pressure side wall and the suction side wall; forming a first intermediate cooling channel defined between the front rib and the intermediate rib, wherein the first cooling path extends from the first leading edge cooling channel to the inner platform leading edge cooling channel, and extends from the second leading edge cooling channel to the inner platform suction side cooling channel and to the second trailing edge cooling channel, and The second cooling path extends from the first intermediate cooling channel to the inner platform pressure side cooling channel.
19. The method according to claim 12, further comprising: positioning an intermediate rib in the intermediate region between the pressure side wall and the suction side wall; forming a first intermediate cooling passage defined between the leading edge rib and the intermediate rib; as well as forming a leading edge cooling channel defined between the leading edge rib and the leading edge, wherein the first cooling path extends from the leading edge cooling channel into the inner platform suction side cooling channel and into the second trailing edge cooling channel, and The second cooling path extends from the first intermediate cooling channel to the inner platform pressure side cooling channel and the inner platform leading edge cooling channel.
20. The method according to claim 11, further comprising: coupling a cover to one of the inner platform and the outer platform; forming a connecting flow channel in the cover, Wherein, the second cooling path extends outwardly from the airfoil to one of the inner platform and the outer platform and extends back into the airfoil through the connecting flow channel forming a serpentine flow path.