COOLING TURBINE BLADES

FIELD OF THE INVENTION

[0001] This invention relates generally to a flow inducer assembly and a method for cooling turbine blades of a gas turbine engine, in particular, the last stage turbine blades of the gas turbine engine, using ambient air.

DESCRIPTION OF THE RELATED ART

[0002] An industrial gas turbine engine typically includes a compressor for compressing air, a combustor for mixing the compressed air with fuel and igniting the mixture, a turbine section for producing mechanical power, and a generator for converting the mechanical power to an electrical power. The turbine section includes a plurality of turbine blades that are attached on a rotor disk. The turbine blades are arranged in rows axially spaced apart along the rotor disk and circumferentially attached to a periphery of the rotor disk. The turbine blades are driven by the ignited hot gas from the combustor and are cooled using a coolant, such as a cooling fluid, through cooling passages in the turbine blades.

[0003] Typically, cooling fluid may be supplied by bleeding compressor air.

However, bleeding air from the compressor may reduce turbine engine efficiency. Due to high operation pressures of the first, second and third stage turbine blades, bleeding compressor air may be required for cooling the first, second and third stage turbine blades. The last stage turbine blades operate under the lowest pressure, ambient air may be used for cooling the last stage turbine blades. In order to sufficiently cool the last stage turbine blades to achieve required boundary conditions, an efficient flow inducer system is needed to bring sufficient amount of the ambient air into cooling passages of the last stage turbine blade. There is a need to provide an easy and simple system to capture sufficient amount of ambient air into the cooling passages of the last stage turbine blade for sufficiently cooling the last stage turbine blades.

SUMMARY OF THE INVENTION

[0004] Briefly described, aspects of the present invention relate to a gas turbine engine and a method for cooling turbine blades of a gas turbine engine.

[0005] According to an aspect, a gas turbine engine is presented. The gas turbine engine comprises a rotor disk comprising a plurality of circumferentially distributed disk grooves. Each disk groove comprises a blade mounting section and a disk cavity. The gas turbine engine comprises a plurality of turbine blades. Each turbine blade comprises a blade root that is inserted into the blade mounting section of the disk groove. The gas turbine engine comprises a plurality of seal plates attached to aft side circumference of the rotor disk. Each seal plate comprises an upper seal plate wall and a lower seal plate wall. The upper seal plate wall is configured to cover the blade root. The gas turbine engine comprises a plurality of flow inducer assemblies. Each flow inducer assembly is configured to be mountable along a downstream side of the disk cavity with respect to a rotation direction of the rotor disk after assembly. The flow inducer assembly is configured to function as a paddle due to rotation of the rotor disk during operation of the gas turbine engine to induce a cooling fluid into the disk cavity and enter inside of the turbine blade from blade root for cooling the turbine blade.

[0006] According to an aspect, a method cooling turbine blades of a gas turbine engine is presented. The gas turbine engine comprises a rotor disk comprising a plurality of circumferentially distributed disk grooves. Each disk groove comprises a blade mounting section and a disk cavity. The gas turbine engine comprises a plurality of turbine blades. Each turbine blade comprises a blade root that is inserted into the blade mounting section of the disk groove. The method comprises attaching a plurality of seal plates to aft side circumference of the rotor disk. Each seal plate comprises an upper seal plate wall and a lower seal plate wall. The upper seal plate wall is configured to cover the blade root. The method comprises mounting a plurality of flow inducer assemblies to the seal plates. Each flow inducer assembly is configured to be mountable along a downstream side of the disk cavity with respect to a rotation direction of the rotor disk after assembly. The flow inducer assembly is configured to function as a paddle due to rotation of the rotor disk during operation of the gas turbine engine to induce a cooling fluid into the disk cavity and enter inside of the turbine blade from blade root for cooling the turbine blade.

[0007] Various aspects and embodiments of the application as described above and hereinafter may not only be used in the combinations explicitly described, but also in other combinations. Modifications will occur to the skilled person upon reading and understanding of the description.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Exemplary embodiments of the application are explained in further detail with respect to the accompanying drawings. In the drawings.

[0009] FIG. 1 illustrates a schematic perspective view of a portion of a gas turbine engine showing the last stage, in which embodiments of the present invention may be incorporated; and

[0010] FIGs. 2 to 38 illustrate schematic perspective views of a flow inducer assembly according to various embodiments of the present invention.

[0011] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures.

DETAILED DESCRIPTION OF THE INVENTION

[0012] A detailed description related to aspects of the present invention is described hereafter with respect to the accompanying figures. [0013] FIG. 1 illustrates a schematic perspective view of a portion of a gas turbine engine 100 showing the last stage looking in an aft side with respect to an axial flow direction. The gas turbine engine 100 includes a flow inducer assembly 300 according to embodiments of the present invention. As illustrated in FIG. 1, the gas turbine engine 100 includes a last stage rotor disk 120 and a plurality of last stage turbine blades 140 that are attached along an outer circumference of the rotor disk 120. A plurality of seal plates 200 are attached to the aft side circumference of the last stage rotor disk 120. The seal plate 200 may prevent hot gas coming into the aft side of the rotor disk 120. The seal plates 200 are secured to the rotor disk 120. The rotor disk 120 may rotate in a direction as indicated by the arrow R during operation of the gas turbine engine 100, which rotates the turbine blades 140 and the seal plates 200 therewith in the same direction R. For clarity purpose, one turbine blade 140 and one seal plate 200 are removed from the rotor disk 120.

[0014] With reference to FIG. 1, the rotor disk 120 includes a plurality of disk grooves 122. Each disk groove 122 includes a blade mounting section 124 and a disk cavity 126. Each turbine blade 140 includes a platform 142 and a blade root 144 that extends radially downward from the platform 142. Each turbine blade 140 is attached to the rotor disk 120 by inserting the blade root 144 into the blade mounting section 124 of the rotor disk groove 122. The disk cavity 126 is formed between the blade root 144 and bottom of the disk groove 122. Each seal plate 200 includes an upper seal plate wall 220, a lower seal plate wall 240 and a seal arm 230 extending axially outward between therein. The upper seal plate wall 220 covers the blade root 144. A flow inducer assembly 300 is attached to the lower seal plate wall 240. The flow inducer assembly 300 aligns with the disk cavity 126 of the disk groove 122.

[0015] During engine operation, rotation of the last stage turbine blades 140 creates pumping force to drive cooling fluid into the disk cavity 126 of the disk groove 120 as indicated by the cooling flow arrow 130 due to centrifugal force. The cooling fluid enters inside of the turbine blade 140 from the blade root 144 for cooling the turbine blade 140 and exits through openings in the turbine blade 140 to gas path of the gas turbine engine 100. The cooling fluid may be ambient air. The flow inducer assembly 300 may provide further driving force to induce ambient air entering the disk cavity 126 of the disk groove 120 as indicated by the cooling flow arrow 130 for sufficiently cooling the last stage turbine blade 140. According to embodiments of the present invention, the flow inducer assembly 300 and the seal plate 200 may be manufactured separately using conventional machining method. The flow inducer assembly 300 may be mountable to the seal plate 200 which enables using ambient air for sufficiently cooling the last stage turbine blades 140. The flow inducer assembly 300 may be removable from the seal plate 200 when alternative cooling fluid, such as compressed air, is used for cooling the turbine blades 140. The seal plate 200 is a modular piece that may support different cooling sources for cooling the turbine blades 140. Such arrangement provides flexibility for manufacturing and flexibility for using different cooling sources, such as compressed air and ambient air, with minimum cost.

[0016] FIG. 2 illustrates a schematic perspective assembled view of a seal plate 200 having a flow inducer assembly 300 mounted to the seal plate 200 according to an embodiment of the present invention. As shown in FIG. 2, the seal plate 200 includes an upper seal plate wall 220 and a lower seal plate wall 240. A seal arm 230 extends axially outward between the upper seal plate wall 220 and the lower seal plate wall 240. The seal plate 200 may have a hook 202 displaced at a side of the upper seal plate wall 220 facing to the rotor disk 120. The hook 202 may have a U-shape that attaches to the rotor disk 120. The seal plate 200 may have a protrusion 204 protruded from a side of the lower seal plate wall 240 facing to the rotor disk 120. The protrusion 204 may have a dovetail shape that attaches to the rotor disk 120. The hook 202 and the protrusion 204 secure the seal plate 200 to the rotor disk 120. The seal plate 200 has an aperture 242 axially penetrating through the lower seal plate wall 240. The aperture 242 may be located at the lower seal plate wall 240 with a radial distance below the seal arm 230. The aperture 242 may align with the disk cavity 126 of the disk groove 122 after assembly. The aperture 242 may generally have a similar shape with the disk cavity 126. [0017] With reference to FIG. 2, a flow inducer assembly 300 is mounted to the seal plate 200 extending outward in an axial direction. The flow inducer assembly 300 may include a curved plate 310 attached radially along the aperture 242 at a downstream side with respect to the rotation direction R of the rotor disk 120 as shown in FIG. 1. The curved plate 310 may extends outward in an axial direction at a front surface of the lower seal plate wall 240 facing away from the rotor disk 120. The curved plate 310 may extend axially perpendicularly to the lower seal plate wall 240. The curved plate 310 may have a similar curvature with the aperture 242. During operation of the gas turbine engine 100, rotation of the rotor disk 120 and the seal plate 200 therewith makes the curved plate 310 of the flow inducer assembly 300 functioned as a paddle that drives cooling air 130, such as ambient air from outside of the gas turbine engine 100, in addition to centrifugal force caused by rotation of the turbine blades 140, into the aperture 242 and the disk cavity 126 and enters insides of the turbine blades 140 from the blade roots 144 for cooling the turbine blades 140. The curved plate 310 may have a scoop shape.

[0018] Dimensions of the flow inducer assembly 300 may be designed to achieve cooling requirement for sufficiently cooling the turbine blades 140. Dimensions of the flow inducer assembly may include a radial height of the curved plate 310, an axial length of the curved plate 310, etc. A radial height of the curved plate 310 may be less than, or equal to, or greater than a radial height of the aperture 242. For illustration purpose, FIG. 2 shows a radial height of the curved plate 310 that is equal to a radial height of the aperture 242. As illustrated in FIG. 2, the curved plate 310 is attached along the aperture 242 at the downstream side starting from the lowest point of the aperture 242 and ending at the highest point of the aperture 242. It is understood that the curved plate 310 may be attached along the aperture 242 at the downstream starting at a radial point that is below the lowest point of the aperture 242, or above the lowest point of the aperture 242. It is also understood that the curved plate 310 may be attached along the aperture 242 at the downstream side ending at a radial point that is below the highest point of the aperture 242, or between the highest point of the aperture 242 and the seal arm 230, or attached to the seal arm 230.

[0019] An axial length of the curved plate 310 may change along a radial direction. According to exemplary embodiments as illustrated in FIG. 2, the axial length of the curved plate 310 may be shorter in the lower portion and longer in the upper portion. For example, the maximum axial length of the curved plate 310 from the lower seal plate wall 240 may be located at the upper portion of the curved plate 310 that is near a region of the top of the curved plate 310.

[0020] FIGs. 3 to 5 illustrate schematic perspective views of a flow inducer assembly 300 having means to mount to a seal plate 200 and the seal plate 200 looking backward and an assembled seal plate 200 with the flow inducer assembly 300 mounted therein looking backward according to an embodiment of the present invention. With references to FIGs. 3 to 5, the curved plate 310 may include a backward tab 311 extending out in a circumferential direction from backend of the curved plate 310. The backward tab 311 includes a hole 312 penetrating through the backward tab 311. The seal plate 200 includes an undercut 241 on the back surface of the lower seal plate wall 240 facing to the rotor disk 120. The undercut 241 is located at the downstream side of the aperture 242. The undercut 241 has a shape corresponding to the shape of the backward tab 311. A hole 243 is in the undercut 241 penetrating through the lower seal plate wall 240. The flow inducer assembly 300 is inserted through the aperture 242 from the front surface of the seal plate 200. The backward tab

311 flushes within the undercut 241 of the lower seal plate wall 240. The hole 312 of the backward tab 311 aligns with the hole 243 in the undercut 241. The curved plate 310 aligns along the aperture 242 at the downstream side from the front surface of the lower seal plate wall 240. The flow inducer assembly 300 is then mounted to the seal plate 200 by a fastener 313 penetrating through the hole 312 of the backward tab 311 into the hole 243 of the seal plate 200. The fastener 313 may include a bolt. The holes

312 and 243 may be threaded inside. The flow inducer assembly 300 may be removed from the seal plate 200 when alternative cooling fluid, such as compressed air, is used for cooling the turbine blades 140. The seal plate 200 is a modular piece that may support different cooling sources for cooling the turbine blades 140.

[0021] FIGs. 6 and 7 illustrate schematic perspective views of a flow inducer assembly 300 having means to mount to a seal plate 200 and an assembled seal plate 200 with the flow inducer assembly 300 mounted therein looking forward according to an embodiment of the present invention. With references to FIGs. 6 to 7, the seal plate 300 includes a backward tab 311 and a forward tab 314 extending out in the

circumferential direction. The forward tab 314 may be parallel to the backward tab 311 and spaced apart from the backward tab 311 in an axial direction. The axial distance between the forward tab 314 and the backward tab 311 may equal to a thickness of the lower seal plate wall 240. The flow inducer assembly 300 is inserted through the aperture 242 from the front surface of the seal plate 200. The backward tab 311 flushes within the undercut 241 of the lower seal plate wall 240 as illustrated in FIGs. 3 to 5. The hole 312 of the backward tab 311 aligns with the hole 243 in the undercut 241. The curved plate 310 aligns along the aperture 242 at the downstream side from the front surface of the lower seal plate wall 240. The forward tab 314 attaches to the front surface of the lower seal plate wall 240 at the downstream side of the aperture 242. The flow inducer assembly 300 is mounted to the seal plate 200 by the fastener 313 penetrating through the hole 312 of the backward tab 311 into the hole 243 of the seal plate 200. The fastener 313 may include a bolt. The flow inducer assembly 300 may be removed from the seal plate 200 when alternative cooling fluid, such as compressed air, is used for cooling the turbine blades 140. The seal plate 200 is a modular piece that may support different cooling sources for cooling the turbine blades 140.

[0022] FIGs. 8 to 10 illustrate schematic perspective views of a flow inducer assembly 300 having means to mount to a seal plate 200 and the seal plate 200 looking backward and an assembled seal plate 200 with the flow inducer assembly 300 mounted therein looking backward according to an embodiment of the present invention. With references to FIGs. 8 to 10, the curved plate 310 includes a flange 315 extending out in a circumferential direction at a backend of the curved plate 310 and radially along the curved plate 310. The seal plate 200 includes an undercut 241 on the back surface of the lower seal plate wall 240 facing to the rotor disk 120. The undercut 241 is located at the downstream side of the aperture 242. The undercut 241 has a shape corresponding to the shape of the flange 315. The flow inducer assembly 300 is inserted through the aperture 242 from the back surface of the seal plate 200. The flange 315 flushes within the undercut 241 of the lower seal plate wall 240 to secure the flow inducer assembly 300 to the seal plate 200. The curved plate 310 aligns along the aperture 242 at the downstream side from a front surface of the lower seal plate wall 240. The flow inducer assembly 300 may be removed from the seal plate 200 when alternative cooling fluid, such as compressed air, is used for cooling the turbine blades 140. The seal plate 200 is a modular piece that may support different cooling sources for cooling the turbine blades 140.

[0023] FIG. 11 illustrates a schematic perspective assembled view of a seal plate 200 having a flow inducer assembly 300 mounted to the seal plate 200 according to an embodiment of the present invention. As shown in FIG. 11, the flow inducer assembly 300 may include a floor plate 320 attached to the lower seal plate wall 240 extending axially outward from the lower seal plate wall 240 at a radial location of the lowest point of the aperture 242. The floor plate 320 may be parallel to the seal arm 230 of the seal plate 200. The flow inducer assembly 300 may include an inner side wall 330 and an outer side wall 340 radially attached between the floor plate 320 and the seal arm 230. The inner side wall 330 and the outer side wall 340 are spaced apart from each other and attached at two circumferential sides of the aperture 242 forming a partial annular shape. The inner side wall 330 may be attached to the aperture 242 at the upstream side. The outer side wall 340 may be attached to the aperture 242 at the downstream side. The inner side wall 330 and the outer side wall 340 may be two curved plates. The arc length of the outer side wall 340 is longer than the arc length of the inner side wall 330 forming an inlet 350 facing to the rotation direction R of the rotor disk 120. During operation of the gas turbine engine 100, rotation of the rotor disk 120 and the seal plate 200 therewith makes the flow inducer assembly 300 functioned as a paddle that induces cooling air 130, such as ambient air from outside of the gas turbine engine 100, in addition to centrifugal force caused by rotation of the turbine blades 140, into the flow inducer assembly 300 through the inlet 350, flow into the aperture 242 and the disk cavity 126 and enters insides of the turbine blades 140 from the blade roots 144 for cooling the turbine blades 140.

[0024] Dimensions of the flow inducer assembly 300 may be designed to achieve cooling requirement for sufficiently cooling the turbine blades 140. Dimensions of the flow inducer assembly 300 may include radial heights of the inner side wall 330 and the outer side wall 340, circumferential distance between the inner side wall 330 and the outer side wall 340, orientation of the inlet 350 with respect to ration direction R of the rotor disk 120, etc. The radial heights of the of the inner side wall 330 and the outer side wall 340 are defined by a radial distance between the floor plate 320 and the seal arm 230. The floor plate 320 may be attached to the lower seal plate wall 240 at a radial location of the lowest radial point of the aperture 242, as illustrated in FIG. 8. It is understood that the floor plate 320 may be attached to the lower seal plate wall 240 at a radial location below the lowest radial point of the aperture 242. The inner side wall 330 and the outer side wall 340 may be located at upstream and downstream edges of the aperture 242, or further away from the upstream and downstream edges of the aperture 242. Orientation of the inlet 350 may be perpendicularly to the rotation direction R which may drive more cooling air into the flow inducer assembly 300 in comparison with the orientation of the inlet 350 with an angle that is less than or greater than 90° with respect to the rotation direction R.

[0025] FIG. 12 illustrates a schematic perspective view of the flow inducer assembly 300 having means to mount to the seal plate 200 according to an embodiment as shown in FIG. 11. With references to FIGs. 11 and 12, the flow inducer assembly 300 includes a radial tab 321 extending radially downward from the floor plate 320 at a backend. The radial tab 321 includes a hole 312 penetrating through the radial tab 321. The flow inducer assembly 300 is mounted to the seal plate 200 by a fastener 313 penetrating through the hole 312 to the front surface of the lower seal plate wall 240. The front surface of the lower seal plate wall 240 may have a hole to receive the fastener 313. The fastener 313 may include a bolt. The hole 312 may be threaded inside. The flow inducer assembly 300 may be removed from the seal plate 200 when alternative cooling fluid, such as compressed air, is used for cooling the turbine blades 140. The seal plate 200 is a modular piece that may support different cooling sources for cooling the turbine blades 140.

[0026] FIGs. 13 and 14 illustrate schematic perspective views of an assembled seal plate 200 with a flow inducer assembly 300 mounted to the seal plate 200 and the flow inducer assembly 300 having means to mount to the seal plate 200 according to an embodiment of the present invention. With references to FIGs. 13 and 14, the floor plate 320 is laterally extended out the outer side wall 340. A vertical plate 342 is attached to the outer side wall 340 at the extended area of the floor plate 320 and radially attached between the floor plate 320 and the seal arm 230. The outer side wall 340 and the vertical plate 342 may be formed as Y-shape. The floor plate 320 may be also laterally extended out the inner side wall 330 and attached to the lower seal plate wall 240. The configuration of the flow inducer assembly 300 as shown in FIG.13 may improve mechanical properties of the flow inducer assembly 300, such as increasing mechanical strength, reducing vibration, etc. The flow inducer assembly 300 includes a radial tab 321 extending radially downward from the floor plate 320 at a backend. The radial tab 321 includes a hole 312 penetrating through the radial tab 321. The flow inducer assembly 300 is mounted to the seal plate 200 by a fastener 313 penetrating through the hole 312 to the front surface of the lower seal plate wall 240. The front surface of the lower seal plate wall 240 may have a hole to receive the fastener 313.

The fastener 313 may include a bolt. The hole 312 may be threaded inside. The flow inducer assembly 300 may be removed from the seal plate 200 when alternative cooling fluid, such as compressed air, is used for cooling the turbine blades 140. The seal plate 200 is a modular piece that may support different cooling sources for cooling the turbine blades 140.

[0027] FIGs. 15 to 17 illustrate schematic perspective views of an assembled seal plate 200 with a flow inducer assembly 300 mounted therein and the seal plate 200 and the flow inducer assembly 300 having means to mount to the seal plate 200 according to an embodiment of the present invention. With references to FIGs. 15 to 17, the seal plate 200 includes a root 244 attached to the lower seal plate wall 240 extending radially downward. The root 244 may have a dovetail shape. A slot 247 is arranged at bottom of the root 244 of the seal late 200 in a circumferential direction. The flow inducer assembly 300 includes a curved plate 310. The curved plate 310 may have a semi hollow cylindrical shape. Shape of the curved plate 310 may align with a shape of the disk cavity 126 of the rotor disk 120. A panel 317 is arranged at the backend of the curved plate 310 in a circumferential direction. The flow inducer assembly 300 is mounted to the seal plate 200 by inserting the circumferential panel 317 into the circumferential slot 247 of the root 244 of the lower seal plate wall 240. Front side of the curved plate 310 is tilted toward to the rotation direction R of the rotor disk 120 such that the longer axial side of the curved plate 310 is displaced along a downstream side of the disk cavity 126 with respect to the rotation direction R of the rotor disk 120 after assembly.

[0028] FIG. 18 illustrates a schematic perspective view of a portion of a gas turbine engine 100 showing the last stage looking in an aft side with respect to an axial flow direction. The gas turbine engine 100 includes the flow inducer assembly 300 as illustrated in FIGs. 15 to 17. As shown in FIG. 18, the seal plate 200 is attached to the rotor disk 120. The root 244 of the seal plate 200 is displaced into the disk cavity 126. The flow inducer assembly 300 is mounted to the root 244 of the seal plate 200 and is displaced into the disk cavity 126. Front side of the curved plate 310 of the flow inducer assembly 300 is tilted toward to the rotation direction R of the rotor disk 120 such that the longer axial side of the curved plate 310 is displaced along a downstream side of the disk cavity 126 with respect to the rotation direction R of the rotor disk 120 after assembly. During operation of the gas turbine engine 100, rotation of the rotor disk 120 and the seal plate 200 therewith makes the flow inducer assembly 300 functioned as a paddle that induces cooling air 130, such as ambient air, into the curved plate 310 and the disk cavity 126 and enters insides of the turbine blades 140 from the blade roots 144 for cooling the turbine blades 140. A locking plate 246 may be inserted into a disk slot 128 for securing the seal plate 200 to the rotor disk 120. FIG. 19 illustrates a schematic perspective view of a locking plate 246 as shown in FIG. 18. The flow inducer assembly 300 may be removed from the seal plate 200 when alternative cooling fluid, such as compressed air, is used for cooling the turbine blades 140. The seal plate 200 is a modular piece that may support different cooling sources for cooling the turbine blades 140.

[0029] FIGs. 20 to 22 illustrate schematic perspective views of an assembled seal plate 200 with a flow inducer assembly 300 mounted therein and the seal plate 200 and the flow inducer assembly 300 having means to mount to the seal plate 200 according to an embodiment of the present invention. With references to FIGs. 20 to 22, a slot 248 is arranged at bottom of the root 244 of the seal plate 200 in an axial direction. The axial slot 248 may have a dovetail shape. The flow inducer assembly 300 may include an axial panel 316 and a circumferential panel 317. The axial panel 316 and the circumferential panel 317 may be formed as T-shape. The flow inducer assembly 300 may include a curved plate 310 arranged at a downstream side of the circumferential panel 317. The curved plate 310 may have a shape that aligns with a shape of the disk cavity 126. The curved plate 310 may have a scoop shape. The axial panel 316 may have a dovetail shape that mates with the dovetail shaped axial slot 248. The flow inducer assembly 300 is mounted to the seal plate 200 by inserting the axial panel 316 into the axial slot 248 of the root 244 of the seal plate 200 and locked therein by the dovetail locking engagement.

[0030] FIG. 23 illustrates a portion of a gas turbine engine 100 showing the last stage looking in an aft side with respect to an axial flow direction. The gas turbine engine 100 includes the flow inducer assembly 300 as illustrated in FIGs. 20 to 22. As shown in FIG. 23, the seal plate 200 is attached to the rotor disk 120. The root 244 of the seal plate 200 is displaced into the disk cavity 126. The flow inducer assembly 300 is mounted to the root 244 of the seal plate 200. The curved plate 310 of the flow inducer assembly 300 is displaced along a downstream side of the disk cavity 126 with respect to the rotation direction R of the rotor disk 120 after assembly. During operation of the gas turbine engine 100, rotation of the rotor disk 120 and the seal plate 200 therewith makes the flow inducer assembly 300 functioned as a paddle that induces cooling air 130, such as ambient air, in addition to centrifugal force caused by rotation of the turbine blades 140, into the disk cavity 126 and enters insides of the turbine blades 140 from the blade roots 144 for cooling the turbine blades 140. A locking plate 246 may be inserted into a disk slot 128 for securing the seal plate 200 to the rotor disk 120. The flow inducer assembly 300 may be removed from the seal plate 200 when alternative cooling fluid, such as compressed air, is used for cooling the turbine blades 140. The seal plate 200 is a modular piece that may support different cooling sources for cooling the turbine blades 140.

[0031] FIGs. 24 to 26 illustrate schematic perspective views of a flow inducer assembly 300 having means to mount to the seal plate 200 according to various embodiments of the present invention. With reference to FIG. 24, the curved plate 310 may include a radial tab 318 extending radially downward. The radial tab 318 may be located at the lowest radial end of the curved plate 310. The radial tab 318 may include a hole 312 penetrating through the radial tab 318. A fastener 313 may penetrate through the hole 312 of the radial tab 318 into aft side surface of the rotor disk 120 after assembly to secure the flow inducer assembly 300 to the rotor disk 120. The aft side surface of the rotor disk 120 may include a hole to receive the fastener 313. The fastener 313 may include a bolt. With reference to FIG. 25, the curved plate 310 may include a flange 315 extending out in a circumferential direction at a backend of the curved plate 310 and radially along the curved plate 310. The flange 315 may attach to the disk cavity 126 at the downstream side of the disk cavity 126 after assembly. With reference to FIG. 26, the flow inducer assembly 300 may include a curved plate 310 attached to the axial panel 316 in a circumferential direction. The curved plate 310 may have a semi hollow cylindrical shape. Shape of the curved plate 310 may align with a shape of the disk cavity 126 of the rotor disk 120. Front side of the curved plate 310 is tilted toward to the rotation direction R of the rotor disk 120 such that the longer axial side of the curved plate 310 is displaced along the downstream side of the disk cavity 126 with respect to the rotation direction R of the rotor disk 120 after assembly. The flow inducer assembly 300 illustrated in FIGs. 24 to 26 is mounted to the seal plate 200 by inserting the axial panel 316 into the axial slot 248 of the root 244 of the seal plate 200 as shown in FIGs. 20 to 23, which are not described in detail herewith. The flow inducer assembly 300 may be removed from the seal plate 200 when alternative cooling fluid, such as compressed air, is used for cooling the turbine blades 140. The seal plate 200 is a modular piece that may support different cooling sources for cooling the turbine blades 140.

[0032] FIGs. 27 to 29 illustrate schematic perspective views of an assembled seal plate 200 with a flow inducer assembly 300 mounted therein and the seal plate 200 and the flow inducer assembly 300 having means to mount to the seal plate 200 according to an embodiment of the present invention. With references to FIGs. 27 to 29, a slot 249 is arranged at a side surface of the root 244 of the seal plate 200 facing away from the rotor disk 120. The slot 249 is arranged in a circumferential direction. The circumferential slot 249 may have a dovetail shape. The flow inducer assembly 300 may include a circumferential panel 317. The circumferential panel 317 may have a dovetail shape that mates with the dovetail shaped circumferential slot 249. The flow inducer assembly 300 may include a curved plate 310 arranged at a downstream side of the circumferential panel 317. The curved plate 310 may have a shape that aligns with a shape of the disk cavity 126. The curved plate 310 may have a scoop shape. The flow inducer assembly 300 is mounted to the seal plate 200 by inserting the circumferential panel 317 into the circumferential slot 249 of the root 244 of the seal plate 200 and locked therein by the dovetail locking engagement. The flow inducer assembly 300 may have various embodiments as illustrated in FIGs. 24 to 26, which are not described in detail herewith.

[0033] FIG. 30 illustrates a portion of a gas turbine engine 100 showing the last stage looking in an aft side with respect to an axial flow direction. The gas turbine engine 100 includes the flow inducer assembly 300 as illustrated in FIGs. 27 to 29. As shown in FIG. 30, the seal plate 200 is attached to the rotor disk 120. The root 244 of the seal plate 200 is displaced into the disk cavity 126. The flow inducer assembly 300 is mounted to the root 244 of the seal plate 200. The curved plate 310 of the flow inducer assembly 300 is displaced along a downstream side of the disk cavity 126 with respect to the rotation direction R of the rotor disk 120 after assembly. During operation of the gas turbine engine 100, rotation of the rotor disk 120 and the seal plate 200 therewith makes the flow inducer assembly 300 functioned as a paddle that induces cooling air 130, such as ambient air, into the disk cavity 126 and enters insides of the turbine blades 140 from the blade roots 144 for cooling the turbine blades 140. A locking plate 246 may be inserted into a disk slot 128 for securing the seal plate 200 to the rotor disk 120. The flow inducer assembly 300 may be removed from the seal plate 200 when alternative cooling fluid, such as compressed air, is used for cooling the turbine blades 140. The seal plate 200 is a modular piece that may support different cooling sources for cooling the turbine blades 140.

[0034] FIGs. 31 to 33 illustrate schematic perspective views of an assembled seal plate 200 with a flow inducer assembly 300 mounted therein and the seal plate 200 and the flow inducer assembly 300 having means to mount to the seal plate 200 according to an embodiment of the present invention. With references to FIGs. 31 to 33, a slot 249 is arranged at a side surface of the root 244 of the seal plate 200 facing away from the rotor disk 120. The slot 249 is arranged in a circumferential direction. The flow inducer assembly 300 may include a circumferential panel 317 and a curved plate 310 arranged at a downstream side of the circumferential panel 317. The curved plate 310 may have a shape that aligns with a shape of the disk cavity 126. The curved plate 310 may have a scoop shape. The flow inducer assembly 300 is mounted to the seal plate 200 by inserting the circumferential panel 317 into the circumferential slot 249 of the root 244 of the seal plate 200. The flow inducer assembly 300 may have various embodiments as illustrated in FIGs. 24 to 26, which are not described in detail herewith.

[0035] FIG. 34 illustrates a portion of a gas turbine engine 100 showing the last stage looking in an aft side with respect to an axial flow direction. The gas turbine engine 100 includes the flow inducer assembly 300 as illustrated in FIGs. 31 to 33. As shown in FIG. 34, the seal plate 200 is attached to the rotor disk 120. The root 244 of the seal plate 200 is displaced into the disk cavity 126. The flow inducer assembly 300 is mounted to the root 244 of the seal plate 200. The curved plate 310 of the flow inducer assembly 300 is displaced along a downstream side of the disk cavity 126 with respect to the rotation direction R of the rotor disk 120 after assembly. The

circumferential panel 317 is displaced into a disk slot 128. A locking plate 246 may be inserted into the disk slot 128 for securing the flow inducer assembly 300 and the seal plate 200 to the rotor disk 120. During operation of the gas turbine engine 100, rotation of the rotor disk 120 and the seal plate 200 therewith makes the flow inducer assembly 300 functioned as a paddle that induces cooling air 130, such as ambient air, in addition to centrifugal force caused by rotation of the turbine blades 140, into the disk cavity 126 and enters insides of the turbine blades 140 from the blade roots 144 for cooling the turbine blades 140.

[0036] FIGs. 35 and 36 illustrate schematic perspective views of a flow inducer assembly 300 and a portion of a gas turbine engine 100 having the flow inducer assembly 300 mounted to the rotor disk 120 according to an embodiment of the present invention. With references to FIG. 35, the flow inducer assembly 300 may include a curved plate 310. The curved plate 310 may include a backward tab 311 extending out in a circumferential direction from backend of the curved plate 310. A block 319 may be arranged at corner of the curved plate 310 and the backward tab 311 to enhance mechanical strength of the flow inducer assembly 300. With refence to FIG. 36, the seal plate 200 is attached to the rotor disk 120. The root 244 of the seal plate 200 is displaced into the disk cavity 126. The flow inducer assembly 300 is mounted to the rotor disk 120 by inserting the backward tab 311 into a disk slot 128 of the rotor disk 120 such that the curved plate 310 is displaced along the downstream side of the disk cavity 126 with respect to the rotation direction R of the rotor disk 120 after assembly. A locking plate 246 may be inserted into one disk slot 128 for securing the seal plate 200 to the rotor disk 120. The flow inducer assembly 300 may be removed from the rotor disk 120 when alternative cooling fluid, such as compressed air, is used for cooling the turbine blades 140. The seal plate 200 is a modular piece that may support different cooling sources for cooling the turbine blades 140.

[0037] FIGs. 37 and 38 illustrate schematic perspective views of a flow inducer assembly 300 and a portion of a gas turbine engine 100 having the flow inducer assembly 300 mounted to the rotor disk 126 according to an embodiment of the present invention. With references to FIG. 37, the flow inducer assembly 300 may include a curved plate 310. The curved plate 310 may be attached to the locking plate 246 at a downstream side. A block 319 may be arranged at comer of the curved plate 310 and the locking plate 246 to enhance mechanical strength of the flow inducer assembly 300. With reference to FIG. 38, the seal plate 200 is attached to the rotor disk 120. The root 244 of the seal plate 200 is displaced into the disk cavity 126. The flow inducer assembly 300 is mounted to the rotor disk 120 by inserting the locking plate 246 into a disk slot 128 of the rotor disk 120 such that the curved plate 310 is displaced along the downstream side of the disk cavity 126 with respect to the rotation direction R of the rotor disk 120 after assembly. The locking plate 246 may also secure the seal plate 200 to the rotor disk 120. The flow inducer assembly 300 may be removed from the rotor disk 120 when alternative cooling fluid, such as compressed air, is used for cooling the turbine blades 140. The seal plate 200 is a modular piece that may support different cooling sources for cooling the turbine blades 140.

[0038] According to an aspect, the proposed flow inducer assembly 300 may enable using ambient air as cooling fluid 130 for sufficiently cooling the last stage of turbine blades 140 of a gas turbine engine 100. During operation of the gas turbine engine 100, rotation of the rotor disk 120 and the seal plate 200 therewith makes the flow inducer assembly 300 functioned as a paddle that induces sufficient amount of ambient air from outside of the gas turbine engine 100 as the cooling air 130 into disk cavities 126 of rotor disk 120 and enters insides of the turbine blades 140 from the blade roots 144 for cooling the turbine blades 140. The proposed flow inducer assembly 300 eliminates bleeding compressor air for cooling the last stage of turbine blades 140, which increases turbine engine efficiency.

[0039] According to an aspect, the proposed flow inducer assembly 300 may be manufactured separately as a single piece having means that is mountable to the seal plate 200 or the rotor disk 120 and is removable from the seal plate 200 or the rotor disk 120. Such arrangement provides flexibility for manufacturing the flow inducer assembly 300 and the seal plate 200. For example, the proposed flow inducer assembly 300 and the seal plate 200 may be manufactured separately using conventional machining method which saves manufacturing cost and lead time.

[0040] According to an aspect, the proposed flow inducer assembly 300 may also enable using various cooling fluids for cooling the turbine blades 140. For example, the proposed flow inducer assembly 300 may be mounted to the seal pate 200 or the rotor disk 120 to use ambient air for cooling the turbine blades 140. The proposed flow inducer assembly 300 may be removed from the seal pate 200 or the rotor disk 120 to use compressed air for cooling the turbine blades 140. The proposed flow inducer assembly 300 may enable the seal plate 200 being manufactured as a modular piece which may support various cooling fluids. The proposed flow inducer assembly 300 provides flexibility for using different cooling sources, such as compressed air and ambient air, with minimal cost.

[0041] Although various embodiments that incorporate the teachings of the present invention have been shown and described in detail herein, those skilled in the art can readily devise many other varied embodiments that still incorporate these teachings.

The invention is not limited in its application to the exemplary embodiment details of construction and the arrangement of components set forth in the description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of“including,”“comprising,” or“having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms“mounted,”“connected,”“supported,” and“coupled” and variations thereof are used broadly and encompass direct and indirect mountings, connections, supports, and couplings. Further,“connected” and“coupled” are not restricted to physical or mechanical connections or couplings.

Reference List:

100: Gas Turbine Engine

120: Rotor Disk

122: Disk Groove

124: Blade Mounting Section

126: Disk Cavity

128: Disk Slot

130: Cooling Flow

140: Turbine Blade

142: Blade Platform

144: Blade Root

200: Seal Plate

202: Seal Plate Hook

204: Seal Plate Protrusion

220: Upper Seal Plate Wall

230: Seal Arm

240: Lower Seal Plate Wall

241 : Undercut of Seal Plate

242: Aperture on Lower Seal Plate Wall

243: Hole on Seal Plate

244: Seal Plate Root

246: Locking Plate

247: Root Bottom Circumferential Slot

248: Root Bottom Axial Slot

249: Root Side Circumferential Slot

300: Flow Inducer Assembly

310: Scoop Shaped Curved Plate

311 : Backward Tab

312: Hole

313: Fastener : Forward Tab

: Flange

: Axial Panel

: Circumferential Panel: Radial Tab

: Strength Box

: Floor Plate

: Radial Tab

: Inner Side Wall: Outer Side Wall: Vertical Side Wall: Cooling Fluid Inlet