Airfoil tip pocket with augmentation features
11661853 · 2023-05-30
Assignee
Inventors
- San Quach (East Hartford, CT, US)
- Tracy A. Propheter-Hinckley (Manchester, CT, US)
- Steven Bruce Gautschi (Naugatuck, CT, US)
Cpc classification
F01D5/147
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F05D2260/2212
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01D5/187
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F05D2260/221
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F05D2220/32
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F05D2260/22141
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F05D2260/202
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01D5/186
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Y02T50/60
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
F05D2260/2214
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
F02C7/045
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01D5/14
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01D5/18
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Abstract
A component for a gas turbine engine includes, among other things, an airfoil that includes a pressure sidewall and a suction sidewall that meet together at both a leading edge and a trailing edge, the airfoil extending radially from a platform to a tip, a tip pocket formed in the tip and terminating prior to the trailing edge, and one or more heat transfer augmentation devices formed in the tip pocket.
Claims
1. A component for a gas turbine engine comprising: an airfoil extending in a chordwise direction between a leading edge and a trailing edge and in a thickness direction between a pressure sidewall and a suction sidewall that meet together at both the leading edge and the trailing edge, the airfoil extending in a radial direction from a platform to a tip; a tip pocket formed in the tip and terminating prior to the trailing edge; wherein the tip pocket includes a suction side lip, a pressure side lip, a leading edge lip and a trailing edge lip that each extend outwardly in the radial direction from a floor to the tip; one or more heat transfer augmentation devices formed in the tip pocket, the one or more heat transfer augmentation devices including at least one rib extending from one of the suction side lip and the pressure side lip such that a wall of the at least one rib is spaced apart from another one of the suction side lip and the pressure side lip; wherein the at least one rib extends outwardly in the radial direction from the floor towards the tip such that a length of the at least one rib is slanted at an acute angle in the chordwise direction toward either the leading edge lip or the trailing edge lip relative to the floor; a plurality of cooling holes defined in the floor that fluidly connect the tip pocket to at least one internal cooling cavity formed inside the airfoil, wherein each of the plurality of cooling holes extends along a respective passage axis, the passage axis is angled in the chordwise direction relative to the floor, the plurality of cooling holes includes a first cooling hole and a second cooling hole, the passage axis of the first cooling hole is angled in the chordwise direction towards the leading edge lip relative to the floor, and the passage axis of the second hole is angled in the chordwise direction towards the trailing edge lip relative to the floor; and wherein the at least one rib includes a plurality of ribs distributed along at least one of the suction side lip and the pressure side lip, adjacent ribs of the plurality of ribs establish respective recesses, the recesses extend along the respective one of the suction side lip and the pressure side lip, and the plurality of cooling holes are spaced apart from the plurality of ribs and the recesses.
2. The component as recited in claim 1, wherein at least one of the plurality of cooling holes is angled relative to the floor.
3. The component as recited in claim 1, wherein the plurality of ribs includes a first set of ribs and a second set of ribs, the first set of ribs are distributed along the suction side lip, and the second set of ribs are distributed along the pressure side lip such that the second set of ribs are spaced apart from the suction side lip and from the first set of ribs.
4. The component as recited in claim 3, wherein the length of each rib of the first and second sets of ribs extends from the floor to the tip.
5. The component as recited in claim 3, wherein the plurality of cooling holes are positioned relative to a central axis of the tip pocket, and each wall of the first and second sets of ribs terminates prior to intersecting the central axis.
6. The component as recited in claim 5, wherein the plurality of cooling holes are distributed along the central axis of the tip pocket.
7. The component as recited in claim 5, wherein: the plurality of cooling holes are axially aligned with a respective one of the recesses relative to the central axis of the tip pocket.
8. The component as recited in claim 7, wherein the angle of passage axis differs from the acute angle of each of the plurality of ribs.
9. The component as recited in claim 3, wherein the respective lengths of both the first set of ribs and the second set of ribs are slanted in the chordwise direction toward the leading edge lip relative to the floor.
10. The component as recited in claim 3, wherein the respective lengths of both of the first set of ribs and the second set of ribs are slanted in the chordwise direction toward the trailing edge lip relative to the floor.
11. The component as recited in claim 3, wherein the airfoil is a rotatable turbine blade.
12. A gas turbine engine comprising: a compressor section driven by a turbine section; an airfoil extending radially from a platform, the airfoil including: a tip pocket formed at a tip of the airfoil, the tip pocket extending from a position near a leading edge of the airfoil to a position that is upstream from a trailing edge of the airfoil; wherein the tip pocket includes a suction side lip, a pressure side lip, a leading edge lip and a trailing edge lip that extend radially outwardly from a floor to the tip, and the tip pocket defines a central axis that extends between the leading edge lip and the trailing edge lip; a plurality of heat transfer augmentation devices formed in the tip pocket and that terminate prior to intersecting the central axis of the tip pocket, wherein the plurality of heat transfer augmentation device are a plurality of ribs distributed along at least one of the pressure and suction side lips such that a length of each rib of the plurality of ribs is slanted at an acute angle relative to the floor in a direction towards the leading edge lip or the trailing edge lip; a plurality of cooling holes defined in the floor that fluidly connect the tip pocket to at least one internal cooling cavity formed inside the airfoil, wherein each of the plurality of cooling holes extends along a respective passage axis, the passage axis is angled transversely in a chordwise direction relative to the floor, the plurality of cooling holes includes a first cooling hole and a second cooling hole, the passage axis of the first cooling hole is angled in the chordwise direction towards the leading edge lip relative to the floor, and the passage axis of the second hole is angled in the chordwise direction towards the trailing edge lip relative to the floor; and wherein adjacent ribs of the plurality of ribs establish respective recesses, the recesses extend along the respective one of the suction side lip and the pressure side lip, and the plurality of cooling holes are spaced apart from the plurality of ribs and the recesses.
13. The gas turbine engine as recited in claim 12, wherein the plurality of ribs includes a first set of ribs and a second set of ribs, the first set of ribs are distributed along the suction side lip, and the second set of ribs are distributed along the pressure side lip such that the second set of ribs are spaced apart from the suction side lip and from the first set of ribs.
14. The gas turbine engine as recited in claim 12, wherein the airfoil is a turbine blade in the turbine section.
15. The gas turbine engine as recited in claim 12, wherein the plurality of cooling holes are distributed along the central axis of the tip pocket.
16. The gas turbine engine as recited in claim 15, wherein: the plurality of cooling holes are axially aligned with a respective one of the recesses relative to the central axis of the tip pocket.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION
(25) This disclosure relates to a gas turbine engine component having an airfoil. A tip pocket is formed at a tip of the airfoil. The tip pocket may include one or more heat transfer augmentation devices, such as trip strips, chevrons, or the like, disposed within the tip pocket. The heat transfer augmentation devices may be formed on a suction or pressure side lip of the tip pocket, a floor of the tip pocket, or any combination of locations. These and various other features are discussed in greater detail herein.
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(27) The exemplary engine 20 generally includes a low speed spool 30 and a high speed spool 32 mounted for rotation about an engine central longitudinal axis A relative to an engine static structure 36 via several bearing systems 38. It should be understood that various bearing systems 38 at various locations may alternatively or additionally be provided, and the location of the bearing systems 38 may be varied as appropriate to the application.
(28) The low speed spool 30 generally includes an inner shaft 40 that interconnects a fan 42, a first (or low) pressure compressor 44 and a first (or low) pressure turbine 46. The inner shaft 40 is connected to the fan 42 through a speed change mechanism, which in exemplary gas turbine engine 20 is illustrated as a geared architecture 48 to drive the fan 42 at a lower speed than the low speed spool 30. The high speed spool 32 includes an outer shaft 50 that interconnects a second (or high) pressure compressor 52 and a second (or high) pressure turbine 54. A combustor 56 is arranged in exemplary gas turbine 20 between the high pressure compressor 52 and the high pressure turbine 54. A mid-turbine frame 57 of the engine static structure 36 is arranged generally between the high pressure turbine 54 and the low pressure turbine 46. The mid-turbine frame 57 further supports bearing systems 38 in the turbine section 28. The inner shaft 40 and the outer shaft 50 are concentric and rotate via the bearing systems 38 about the engine central longitudinal axis A which is collinear with their longitudinal axes.
(29) The core airflow is compressed by the low pressure compressor 44 then the high pressure compressor 52, mixed and burned with fuel in the combustor 56, then expanded over the high pressure turbine 54 and low pressure turbine 46. The mid-turbine frame 57 includes airfoils 59 which are in the core airflow path C. The turbines 46, 54 rotationally drive the respective low speed spool 30 and high speed spool 32 in response to the expansion. It will be appreciated that each of the positions of the fan section 22, compressor section 24, combustor section 26, turbine section 28, and fan drive gear system 48 may be varied. For example, gear system 48 may be located aft of combustor section 26 or even aft of turbine section 28, and fan section 22 may be positioned forward or aft of the location of gear system 48.
(30) The engine 20 in one example is a high-bypass geared aircraft engine. In a further example, the engine 20 bypass ratio is greater than about six (6), with an example embodiment being greater than about ten (10), the geared architecture 48 is an epicyclic gear train, such as a planetary gear system or other gear system, with a gear reduction ratio of greater than about 2.3 and the low pressure turbine 46 has a pressure ratio that is greater than about five. In one disclosed embodiment, the engine 20 bypass ratio is greater than about ten (10:1), the fan diameter is significantly larger than that of the low pressure compressor 44, and the low pressure turbine 46 has a pressure ratio that is greater than about five 5:1. Low pressure turbine 46 pressure ratio is pressure measured prior to inlet of low pressure turbine 46 as related to the pressure at the outlet of the low pressure turbine 46 prior to an exhaust nozzle. The gear system 48 may be an epicycle gear train, such as a planetary gear system or other gear system, with a gear reduction ratio of greater than about 2.3:1. It should be understood, however, that the above parameters are only exemplary of one embodiment of a geared architecture engine and that the present invention is applicable to other gas turbine engines including direct drive turbofans and turboshafts.
(31) A significant amount of thrust is provided by the bypass flow B due to the high bypass ratio. The fan section 22 of the engine 20 is designed for a particular flight condition—typically cruise at about 0.8 Mach and about 35,000 feet (10,668 meters). The flight condition of 0.8 Mach and 35,000 ft, with the engine at its best fuel consumption—also known as “bucket cruise Thrust Specific Fuel Consumption (‘TSFC’)”—is the industry standard parameter of lbm of fuel being burned divided by lbf of thrust the engine produces at that minimum point. “Low fan pressure ratio” is the pressure ratio across the fan blade alone, without a Fan Exit Guide Vane (“FEGV”) system. The low fan pressure ratio as disclosed herein according to one non-limiting embodiment is less than about 1.45. “Low corrected fan tip speed” is the actual fan tip speed in ft/sec divided by an industry standard temperature correction of [(Tram ° R)/(518.7° R)].sup.0.5. The “Low corrected fan tip speed” as disclosed herein according to one non-limiting embodiment is less than about 1,150 ft/second (350.5 meters/second).
(32) Each of the compressor section 24 and the turbine section 28 may include alternating rows of rotor assemblies and vane assemblies (shown schematically). For example, the rotor assemblies can carry a plurality of rotating blades 25, while each vane assembly can carry a plurality of vanes 27 that extend into the core flow path C. The blades 25 may either create or extract energy in the form of pressure from the core airflow as it is communicated along the core flow path C. The vanes 27 direct the core airflow to the blades 25 to either add or extract energy.
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(34) In one embodiment, the component 58 includes a platform 60, an airfoil 62 that extends in a first direction from the platform 60, and a root 64 that extends in a second, opposite direction from the platform 60. The airfoil 62 includes a leading edge 66, a trailing edge 68, a pressure sidewall 70 and a suction sidewall 72. The pressure sidewall 70 and the suction sidewall 72 are spaced apart and generally meet together at both the leading edge 66 and the trailing edge 68.
(35) The airfoil 62 connects to the platform 60 at a fillet 69. The root 64 connects to the platform 60 at buttresses 71. The root 64 may include a neck 73 and one or more serrations 75 for securing the component 58 to a disk (not shown).
(36) Although shown schematically in
(37) With reference to the engine 20 of
(38) A tip pocket 80 may be formed in the tip 77 of the airfoil 62. The tip pocket 80 may also be referred to as a squealer pocket. In one embodiment, the tip pocket 80 is part of the internal cooling circuit 81 of the component 58. As discussed in greater detail below, the tip pocket 80 introduces a cooling fluid at the tip 77 of the airfoil 62 to cool the tip 77 and avoid airfoil tip burning.
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(40) The tip pocket 80 terminates prior to, or upstream from, the trailing edge 68 of the airfoil 62. In one embodiment, the tip pocket 80 extends from a position near the leading edge 66 of the airfoil 62 to a position near a mid-span M of the airfoil 62 (see
(41) The tip pocket 80 may include a suction side lip 82, a pressure side lip 84, a leading edge lip 86 and a trailing edge lip 88. The suction side lip 82, the pressure side lip 84, the leading edge lip 86 and the trailing edge lip 88 extend radially outwardly from a floor 90 of the tip pocket 80.
(42) The tip pocket 80 may include one or more heat transfer augmentation devices 92. In one non-limiting embodiment, the heat transfer augmentation device 92 is a trip strip. However, other augmentation devices are also contemplated as being within the scope of this disclosure (see, for example,
(43) In one embodiment, the heat transfer augmentation device 92 axially extends across the suction side lip 82 of the tip pocket 80 between the leading edge lip 86 and the trailing edge lip 88. However, other configurations are also contemplated. For example, the pressure side lip 84 could alternatively or additionally include a heat transfer augmentation device 92.
(44) As best illustrated in the cross-sectional views of
(45) The heat transfer augmentation device(s) 92 are adapted to temporarily trap the cooling fluid F inside the tip pocket 80. For example, the heat transfer augmentation device(s) 92 may temporarily block the cooling fluid F prior to its ejection into a gas stream GS (see
(46) This disclosure is not intended to be limited to the exact configuration of the tip pocket 80 of
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(48) In this embodiment, the heat transfer augmentation devices 192 are formed on both a suction side lip 182 and a pressure side lip 184 of the tip pocket 180 and may extend radially outwardly from a floor 190 of the tip pocket 180. In other words, the heat transfer augmentation devices 192 of this embodiment extend vertically. The heat transfer augmentation devices 192 may extend to the same height as the suction side lip 182 and the pressure side lip 184, in one embodiment.
(49) A plurality of cooling holes 194 extend through the floor 190 of the tip pocket 180. The cooling holes 194 may be positioned along a central axis CA of the tip pocket 180 (see
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(52) The heat transfer augmentation devices 392 may extend from a suction side lip 382 to a pressure side lip 384 of the tip pocket 380. That is, the heat transfer augmentation devices 392 may span an entire distance between the suction side lip 382 and the pressure side lip 384.
(53) In one embodiment, the heat transfer augmentation devices 392 are tapered. For example, as best illustrated in
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(55) Yet another tip pocket 580 is illustrated by
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(57) The heat transfer augmentation device 692 may extend at any angle between a suction side lip 682 and a pressure side lip 684 of the tip pocket 680. In one embodiment, the heat transfer augmentation device 692 is formed by a stepped portion of a floor 690 of the tip pocket 680. For example, the heat transfer augmentation device 692 may include a ramp 691 that extends between a first portion 693 and a second portion 695 of the floor 690. The first portion 693 and the second portion 695 of the floor 690 are radially offset from one another. In other words, the first portion 693 and the second portion 695 of the floor 690 extend in different planes.
(58) Yet another tip pocket 780 is illustrated by
(59) The tip wall configurations of
(60) Although the different non-limiting embodiments are illustrated as having specific components, the embodiments of this disclosure are not limited to those particular combinations. It is possible to use some of the components or features from any of the non-limiting embodiments in combination with features or components from any of the other non-limiting embodiments.
(61) It should be understood that like reference numerals identify corresponding or similar elements throughout the several drawings. It should also be understood that although a particular component arrangement is disclosed and illustrated in these exemplary embodiments, other arrangements could also benefit from the teachings of this disclosure.
(62) The foregoing description shall be interpreted as illustrative and not in any limiting sense. A worker of ordinary skill in the art would understand that certain modifications could come within the scope of this disclosure. For these reasons, the following claims should be studied to determine the true scope and content of this disclosure.