JP2015516053A - Turbine blade trailing edge branch cooling hole - Google Patents

Abstract

A turbine blade of a gas turbine engine having a pressure side wall and a pressure side wall extending outwardly along the blade length and extending in a chord direction between opposing leading and trailing edges. The blade lengthwise rows of spaced, branched trailing edge cooling holes housed in the pressure side wall terminate in corresponding trailing edge cooling slots that extend in the chord direction substantially to the trailing edge. The hole interval wall extending in the axial direction separates the cooling holes. The inlet between adjacent pairs of hole spacing walls includes a gradual inlet portion. The axial inner partition wall divides the cooling holes into the gradually expanding upper gradually expanding portion and the lower gradually expanding portion in the downstream direction and the tail direction of the gradually expanding inlet portion. The front end of the in-hole partition separates the tail end of the gradually expanding inlet portion into an upper inlet channel and a lower inlet channel leading to the upper gradually expanding portion and the lower gradually expanding portion that communicate with the trailing edge cooling slot. [Selection] Figure 1

Description

  The present invention relates generally to the cooling of turbine blades of gas turbine engines, and more particularly to turbine blade trailing edge cooling slots.

  In a gas turbine engine, air is pressurized with a compressor and mixed with fuel in a combustor for generating hot combustion gases. Hot gas is carried through several stages of the turbine, some of which extract energy from the hot gas, which powers the compressor and in typical aircraft turbofan engine applications For example, power is supplied to the upstream fan.

  The turbine stage includes stationary turbine nozzles having rows of hollow vanes that carry combustion gases into corresponding rows of rotor blades that extend radially outward from the support rotor disk. The vanes and blades have corresponding hollow wings with corresponding cooling circuits inside.

  The cooling air is typically compressor discharge air, which is diverted from the combustion process, thus reducing the overall efficiency of the engine. The amount of cooling air needs to be minimized to maximize engine efficiency, but still enough cooling air is operating to properly cool the turbine blades and maximize the useful life of the turbine blades Need to be used. Each wing extends longitudinally or radially outward from the wing base to the tip of the wing and extends axially in the chord direction between the leading and trailing edges, and a generally concave pressure sidewall and an opposite generally convex negative. Includes a compression wall. In turbine blades, the blade length extends from the base of the radially inner base to the radially outer tip spaced from the surrounding turbine shroud. In a turbine vane, the blades extend from a base integral with the radially inner band to a radially outer tip integral with the outer band.

  In addition, each turbine blade initially increases in thickness toward the tail of the leading edge and decreases in thickness to a relatively thin or sharp trailing edge where the pressure and suction sidewalls join. The wide part of the wing has various internal cooling circuits that facilitate heat transfer and cool the inside of the wing and sufficient internal space to accommodate the turbulent wing, but the relatively thin trailing edge is a corresponding limitation Having an internal cooling space.

  Each blade typically includes several rows of membrane cooling holes that extend through the sidewalls of the blade, and the cooling holes release spent cooling air from internal circuitry. The membrane cooling holes are typically tilted towards the trailing edge in the tail direction to form a thin film of cooling air on the outer surface of the blade, which provides additional protection against hot combustion gases flowing over the blade surface during operation Bring an insulated air blanket for.

  The thin trailing edge is typically protected by a row of trailing edge cooling slots that break the pressure sidewall at the outlet just upstream of the trailing edge to release film cooling air onto the pressure sidewall. . Each trailing edge cooling slot has an outlet opening on the pressure side that is radially bounded by a flat portion that begins at the blowout and is exposed at the tail end of the axially extending partition that forms the cooling slot. It may or may not be formed.

  The axial partition may be formed integrally with the pressure side and the suction side of the wing, and themselves need to be cooled by the air released through the cooling slots formed by the partition. The septum typically tapers in the tail direction towards the trailing edge, so the cooling slot is at a shallow progressive angle that promotes diffusion of the cooling air released with little flow separation along the sides of the septum. , Gradually expand towards the trailing edge.

  The aerodynamic and cooling performance of the trailing edge cooling slot is directly related to the specific shape of the cooling slot and the intervening septum. The flow area of the cooling slot regulates the cooling air released through the cooling slot, and the shape of the cooling slot affects its cooling performance.

  The gradual expansion or diffusion angle of the cooling slot may cause undesirable flow separation of the discharged cooling air, which can reduce the performance and cooling effectiveness of the discharged air. This also increases losses that affect turbine efficiency. The portion of the thin trailing edge directly below each cooling slot is effectively cooled by the emitted cooling air, which is also distributed on the exposed flats interposed at the tail ends of the partition walls. . The flat portion is a solid portion formed integrally with the suction side wall in the pressure side wall, and cooling must be relied on the air discharged from the adjacent trailing edge cooling slot.

  Despite the small size of these outlet flats, the considerable cooling performance of the trailing edge cooling slot, the thin trailing edges of the turbine blades are still typically exposed to high operating temperatures in the harsh environment of gas turbine engines. Limit the life of the wing.

  Accordingly, it would be desirable to provide a turbine blade having a cooling slot to improve improved trailing edge cooling, blade durability and engine performance. It is also desirable to minimize the amount of cooling flow used for trailing edge cooling to maximize turbine and engine fuel efficiency.

European Patent Application No. 1505256

  A turbine blade of a gas turbine engine extends outward along the blade length from the blade base to the blade tip and extends in the chord direction between opposing leading and trailing edges, spaced apart in the widthwise pressure side wall and negative pressure. Includes sidewalls. A lengthwise row of branched trailing edge cooling holes spaced apart in the lengthwise direction is accommodated in the pressure side wall and extends substantially in the chord direction to the trailing edge and is correspondingly spaced in the lengthwise direction. Terminate with The cooling holes are separated from each other by a hole interval wall extending in the axial direction. Each of the cooling holes includes a taper inlet between adjacent pairs of hole spacing walls. The tapered gradual inlet includes a tapered inlet portion, a throat portion, and a gradual inlet portion in relation to a cooling flow continuous in the downstream direction. The axial bore walls extending in the downstream direction toward the trailing edge are separated into the blade length direction and gradually expanded in the blade length direction in the downstream direction and tail direction of the gradually increasing inlet portion, and the lower gradually expanding portion. Divide the cooling hole into the part. The front end of the partition wall in the hole is separated from the tail end or the downstream end of the gradually expanding inlet part into an upper inlet channel and a lower inlet channel separated in the blade length direction leading to the upper gradually expanding part and the lower gradually expanding part, respectively. To divide. The upper and lower gradual sections lead to the trailing edge cooling slot.

  The entrance may be a constant area entrance upstream of the gradual entrance. The constant area inlet has a first length extending in the downstream direction and includes a metering portion having a constant area flow cross section, a constant width and a constant height throughout the first length.

  The pressure side wall and the suction side wall may include a pressure side wall surface and a suction side wall surface in the hole, respectively, and the pressure side wall surface may be planar throughout the entire upper gradually expanding portion and the lower gradually expanding portion. The width may be constant throughout the upper and lower gradual portions of the hole.

  The flat portion may be disposed between the blade edge adjacent slots of the trailing edge cooling slots, and the slot floor may be disposed in the trailing edge cooling slot between the flat portions. The flats may be coplanar with or flush with the outer surface of the pressure sidewall around each of the cooling slots. Instead, the flat portion tilts away from the outer surface at a flat portion angle in the range of 0-5 degrees.

  The gradually expanding portion may have a track-like flow cross section. The track-like flow cross-section includes a rounded or semi-circular rectangular portion between the inner and outer ends spaced apart in the wing length direction and having a corner radius. A rounded portion having a rounded radius is in the slot corner between the flat and the slot floor, and the rounded radius is substantially the same size as the corner radius of the flow cross section.

  At least one of the upper gradual portion and the lower gradual portion may include a raised floor that extends at least partially downstream through the cooling slot. Each of the freight floors is in a downstream continuous relationship, with a flat or curved upper ramp in the upper and lower gradual portions, a flat or curved lower ramp in the trailing edge cooling slot, and an upper and lower ramp Transition part between. The upper ramp is inclined upward from the suction side wall surface at the upper gradually expanding portion and the lower gradually expanding portion. The lower ramp is inclined downward and extends in the downstream direction from the transition portion to the trailing edge.

  The flat portion may be inclined away from the outer surface of the pressure side wall and the flat portion toward the slot floor, and may intersect the slot floor upstream of the trailing edge.

  In the following description, the foregoing aspects and other features of the present invention will be described with reference to the accompanying drawings.

FIG. 2 is a longitudinal cross-sectional view of an exemplary embodiment of a turbine vane and rotor blade blade having a branch cooling hole that reaches its highest point in a blade edge spaced apart trailing edge cooling slot. FIG. 2 is an enlarged view of the blade illustrated in FIG. 1. FIG. 3 is a positive pressure side cross-sectional view of a cooling hole having a branch inlet followed by a branch diffusion leading to two of the trailing edge cooling slots illustrated in FIG. 2. FIG. 4 is a schematic cross-sectional view taken along 4-4 of FIG. 3 of one of the two diffusers and the corresponding trailing edge cooling slot. FIG. 4 is a perspective view of the trailing edge cooling slot illustrated in FIG. 3 as viewed from upstream. FIG. 6 is a schematic cross-sectional view taken along 6-6 of FIG. 3 of an elongated flow cross section of a constant width metering section. FIG. 8 is a schematic cross-sectional view taken along 7-7 of FIG. 3 of the elongated flow cross-section of the diffuser. FIG. 4 is a schematic cross-sectional view of a track-like flow cross section having four equal corner radii. FIG. 9 is a schematic cross-sectional view of an alternative track-shaped flow cross section having a height to width ratio greater than the track-shaped flow cross section illustrated in FIG. FIG. 6 is a schematic cross-sectional view of an alternative flow cross section having unequal upper and lower corner radii. FIG. 6 is a schematic cross-sectional view of an alternative alternative flow cross section including four curved quarters that are long and fully curved. FIG. 6 is a schematic cross-sectional view of the curved upper and lower ramps of the raised floor of the cooling holes and trailing edge cooling slots. FIG. 5 is a pressure side cross-sectional view of an alternative inlet having a metering portion of constant width and height. It is a perspective view of one of the measurement parts of FIG.

  Illustrated in FIG. 1 is a high pressure turbine stage 10 of an exemplary gas turbine engine that surrounds an engine center axis 8 and is disposed between a combustor 20 and a low pressure turbine (LPT) 24. The combustor 20 mixes fuel with pressurized air and generates hot combustion gases 19 that flow downstream through the turbine.

  The high pressure turbine stage 10 includes a turbine nozzle 28 upstream of a high pressure turbine (HPT) 22 through which hot combustion gases 19 are released from the combustor 20 into the high pressure turbine. The exemplary embodiment of the high pressure turbine 22 illustrated herein includes at least one row of high pressure turbine blades 32 that are circumferentially spaced apart. Each of the turbine blades 32 includes a turbine blade 12 integrally formed with the base 14, and an axial insertion dovetail 16 that is used to attach the turbine blade to the periphery of the support rotor disk 17.

  Referring to FIG. 2, the blade 12 extends radially outward along the blade length S from the blade base 34 on the blade base 14 to the blade tip 36. During operation, hot combustion gases 19 are generated in the engine and flow downstream beyond the turbine blades 12, which rotate the disks that support the blades and provide power to a compressor (not shown). Extract energy from hot combustion gases. A portion of the pressurized air 18 is suitably cooled and passed through the blade to cool the blade during operation.

  The blade 12 includes a substantially concave pressure side wall 42 and a substantially convex suction side wall 44 that are spaced apart in the width direction. The positive and negative side walls 42, 44 extend longitudinally or radially outward along the blade length S from the blade base 34 to the blade tip 36. The side wall also extends axially in the chord direction C between the opposite leading edge LE and trailing edge TE. The wing 12 is hollow with positive and negative side walls 42, 44 spaced laterally or laterally between the leading edge LE and the trailing edge TE, in which pressurized cooling air or An internal cooling cavity or circuit 54 is formed for circulating the coolant flow 52. The pressurized cooling air or refrigerant stream 52 is part of the pressurized air 18 that is diverted from the compressor.

  The turbine blade 12 increases in width W from the leading edge LE to the maximum width in the tail direction or increases in the width direction, and tapers to a relatively thin or sharp trailing edge TE. Thus, the size of the internal cooling circuit 54 varies with the blade width W and is relatively thin just before the trailing edge where the two sidewalls join together to form the thin trailing edge 56 of the blade 12. At or near the thin trailing edge 56 of the blade 12, a trailing edge cooling slot 66 spaced in the blade length direction is provided to cool the trailing edge.

  Referring to FIG. 3, a row 38 of branched trailing edge cooling holes 30 separated in the blade length direction is formed by being accommodated or embedded in the pressure side wall 42, and is formed in the trailing edge cooling slots 66 separated in the blade length direction. Leads to the corresponding slot. The cooling holes 30 are separated from each other in the radial direction along the blade length S by axial hole spacing walls 80 extending in the downstream direction. The trailing edge cooling slot 66 extends substantially in the chord direction to the trailing edge TE. The trailing edge cooling hole 30 is disposed along the blade length S of the trailing edge TE and communicates with the internal cooling circuit 54 for discharging the refrigerant flow 52 from the internal cooling circuit during operation.

  FIG. 3 shows the trailing edge cooling hole 30 in more detail. Each of the cooling holes 30 includes a tapered progressive inlet 70 located between adjacent pairs of hole spacing walls 80. The inlet 70 includes a tapered inlet portion 106, a throat portion 104, and a gradual inlet portion 108 in relation to a downstream continuous flow. The axial in-hole partition walls 68 extending in the downstream direction toward the trailing edge TE are separated in the blade length direction and gradually expanded in the blade length direction in the downstream direction and the tail direction of the gradually expanding inlet portion 108. The cooling holes 30 are branched into the portions 102 and 103. The front end of the in-hole partition wall 68 is connected to the tail portion or the downstream end 110 of the gradually expanding inlet portion 108 to the upper and lower inlet channels 112 and 114 that are spaced apart in the blade length direction leading to the upper and lower gradually expanding portions 102 and 103, respectively. Separate or split. The front end of the septum 68 is semicircular with a base diameter 73 that defines the beginning of the upper and lower gradual expansion portions 102, 103.

  Each of the upper and lower gradual sections 102, 103 leads to one of the trailing edge cooling slots 66 and supplies cooling air or refrigerant flow 52 for film cooling to the slots. The trailing edge cooling slot 66 begins with a blowout 58 at the downstream end 69 of each of the upper and lower gradual sections 102, 103. The embodiment of the trailing edge cooling slot 66 shown here gradually expands in the blade length direction defined by the blade length S. The in-hole partition wall 68 extends in the downstream direction from the upper and lower flow paths 112 and 114 of the downstream end 110 of the gradually increasing inlet portion 108 toward the rear edge TE, and separates the upper and lower gradually expanding portions 102 and 103 from each other.

  Referring to FIGS. 3-5, the height H in the longitudinal direction of each of the upper and lower gradual expansion portions 102, 103 is as shown in FIG. Defined between the upper and lower hole surfaces 46, 48. As shown in FIG. 4, the hole width W of each of the upper and lower gradually expanding portions 102 and 103 is set so that each of the positive and negative pressure side walls 42 and 44 in each of the upper and lower gradually expanding portions 102 and 103. It is defined between the positive and negative side wall surfaces 39,40. The trailing edge cooling slot 66 includes a slot floor 51 that is open and exposed to the hot combustion gases 19 passing through the high pressure turbine 22. The slot floor 51 extends along the suction side wall 44 over the entire third length L3.

  6 and 7, each of the upper and lower gradual portions 102, 103 has a flow cross section 74 that is generally longer in the blade length direction, and the height H in the blade length direction is substantially greater than the hole width W. It ’s big. Each of the upper and lower gradually expanding portions 102, 103 has a height-width ratio H / W in the range of about 2: 1 to 10: 1 (see FIGS. 4 to 10). The positive and negative pressure side walls 39 and 40 of the positive and negative pressure side walls 42 and 44 form a boundary of the hole 30 in the width direction. The upper and lower gradual expansion portions 102 and 103 and the trailing edge cooling slot 66 have second and third lengths L2 and L3, respectively, extending in the downstream direction, as shown in FIG.

  The embodiment of the upper and lower gradual portions 102, 103 illustrated in FIG. 4 has a fixed or constant width W through the upper and lower gradual portions 102, 103, and the positive and negative side wall surfaces 39, 40 are The upper and lower gradually expanding portions 102 and 103 are parallel throughout the second length L2. The positive pressure side wall surface 39 is flat or planar throughout the second length L2 of the gradually expanding portion. In this embodiment of the cooling hole 30, the suction side wall surface 40 is flat or planar through the entire upper and lower gradual portions 102, 103 and their corresponding second length L 2. The slot floor 51 is coplanar with the suction side wall surface 40 in the hole 30. The upper and lower gradual expansion portions 102, 103 have a constant width W in the embodiment of the trailing edge cooling hole 30 illustrated in FIG. 3 and schematically illustrated in FIG. The upper and lower gradually expanding portions 102 and 103 gradually expand in the blade length direction.

  The upper and lower gradual expansion portions 102 and 103 of the cooling hole 30 lead to a rear edge cooling slot 66 that breaks the outer surface 43 of the pressure side wall 42 with a blowing lip 49 spaced forward or upstream from the rear edge TE. Each trailing edge cooling slot 66 is bounded in the radial or wing length direction by a flat portion 50 exposed in the hole and at the tail end 116 of the hole spacing walls 68, 80. As shown by the solid lines in FIG. 4, the flats 50 are coplanar with or flush with the outer surface 43 of the pressure sidewall 42 around each exposed cooling slot 66 and radially between them. It includes a common blowing lip 49 that extends. This maximizes flow continuity on the pressure side of the blade.

  Referring to FIGS. 4 and 5, the slot surface 60 extends in the width direction between the flat portions 50 along the slot floor 51. The rounded portion 62 of the slot corner 64 between the flat portion 50 and the slot floor 51 has substantially the same size as the bottom corner radius RT of the flow cross section 74 of the gradually expanding portion 102 adjacent to the bottom corner radius RT. It has a good rounding radius RF. The rounding radius RF assists in casting the trailing edge cooling slot 66. The rounding radius RF redistributes the coolant flow 52 from the slot floor 51 to the flat 50 in the trailing edge cooling slot to make the membrane coverage of the coolant flow 52 in the slot floor 51 and the flat 50 more uniform. This helps to improve the cooling of the flat part 50.

  Another embodiment of the flat portion 50 is illustrated in dashed lines in FIG. 4 and is a flat portion that is not coplanar or coplanar with the outer surface 43 of the pressure sidewall 42 around each exposed cooling slot 66. 50 is provided. The flat part 50 may be inclined further away from the outer surface 43 of the pressure side wall 42 toward the slot floor 51. The flat portion 50 may be inclined away from the outer surface 43 at a flat portion angle A3 in the range of 0 to 5 degrees, and the flat portion 50 may intersect the slot floor 51 upstream of the trailing edge TE.

  The embodiment of the flow cross section 74 illustrated in FIGS. 3-6 is a track having a rectangular portion 75 between inner and outer ends 82, 84 that are spaced apart in the wing length or radial direction and rounded or semicircular. The flow cross-section 74 has a shape. FIGS. 8-11 illustrate four exemplary shapes suitable for the flow cross section 74. The track-like flow cross section 74 shown in FIG. 8 is long in the blade length direction, has four equal corner radii R, and has a width-height ratio W / H in the range of 0.25 to 0.50. 9 is long in the blade length direction, has four equal corner radii R, and has a width-height ratio W / H in the range of 0.15 to 0.50. The track-like flow cross section 74 shown in FIG. 10 is similar to that shown in FIG. 8, but has unequal upper and lower corner radii RB, RT. An exemplary range for the corner ratio RB / RT is 1-3. The track-like flow cross section 74 illustrated in FIG. 11 includes a curved quadrant 78 that is long in the wing length direction, fully curved, and may be a combination of ellipses, parabolas or polynomials.

  The cooling holes 30, trailing edge cooling slots 66 and flats 50 are cast into a cooling configuration. Casting these geometries results in good strength, low manufacturing costs and durability of the wings and blades and vanes. Refrigerant required for cooling the blades by means of a track-like flow cross-section 74 with a rectangular part 75 between the inner and outer ends 82, 84 which are spaced apart in the longitudinal or radial direction and rounded or semicircular. Good cooling flow characteristics that reduce the amount of flow 52 are provided. The corner radius R contributes to good cooling, castability and strength of these cooling configurations, and in particular helps to cool the flat 50 and thus reduces the amount of refrigerant flow 52 used.

  The embodiment of cooling hole 30 and trailing edge cooling slot 66 illustrated in FIGS. 3 and 5 includes a progressively expanding trailing edge cooling slot 66. The gradually expanding upper and lower gradually expanding portions 102 and 103 and the corresponding trailing edge cooling slot 66 are gradually expanded at different first and second gradually expanding angles A1 and A2, respectively, as shown in FIG. May be. The height H in the blade length direction of the gradually expanding portions of the cooling hole 30 and the trailing edge cooling slot 66 increases in the downstream direction D. The more preferable flow angle with respect to the flat portion for obtaining the refrigerant flow 52 on the flat portion at the blow-out portion is the expansion angle A1 of the gradually expanding portion of the cooling hole 30, and the gradually expanding angle of the cooling slot and the gradually expanding portion. It is set by the difference between the expansion angle, that is, A2-A1.

  The gradually expanding upper and lower gradually expanding parts 102 and 103 extend the flow application range at the blowing part 58 and make the film application range of the refrigerant flow 52 on the slot floor 51 and the flat part 50 more uniform. Then, the refrigerant flow 52 is redistributed in the trailing edge cooling slot from the slot floor 51 to the flat portion 50. The constant width W of the gradually expanding upper and lower gradually expanding portions 102, 103 helps to maintain complete adhesion of the refrigerant flow 52 at the gradually expanding portion.

  As a result, the surface area of the slot floor 51 can be increased and the surface area of the flat portion 50 can be decreased. The upper and lower gradual portions 102, 103 of constant width W help to set a more preferred flow angle at the outlet relative to the flat portion 50 so as to obtain more refrigerant flow 52 on the flat portion. . The planar pressure side wall surface 39 through the entire second length L2 of the upper and lower gradually expanding portions 102, 103 is also relative to the flat portion 50 so as to obtain more refrigerant flow 52 on the flat portion. It helps to set a more preferred flow angle at the outlet. The constant width of the cooling hole 30 and the planar pressure side wall surface 39 of the cooling hole 30 separately help to maintain the flow of the refrigerant flow 52 attached to the slot extension.

  Another embodiment of the cooling hole 30 is illustrated in dashed lines in FIG. 4, with the upper portion of the hole 30 between the positive and negative side wall surfaces 39, 40 of the positive and negative side walls 42, 44 and A variable width WV is provided instead of the constant width W inside the lower gradually expanding portions 102 and 103. The variable width WV is provided by a raised floor 88 that extends through at least a portion of the upper and lower gradual portions 102, 103 and into the cooling slot 66 at least partially through the cooling slot 66 in the downstream direction. The fried floor 88 is in a downstream continuous relationship with a flat or curved upper ramp 90 in the upper and lower gradual sections 102, 103, a flat or curved lower ramp 94 in the trailing edge cooling slot 66, and an upper and lower portion. And a transition 92 between the lamps 90, 94.

  Flat upper and lower ramps are illustrated in FIG. 4, and curved upper and lower ramps 90, 94 and curved transition 92 are illustrated in FIG. The upper ramp 90 is inclined upward from the negative pressure side wall surface 40 in each of the upper and lower gradually expanding portions 102 and 103 and extends in the downstream direction. The lower ramp 94 is inclined downward and extends in the downstream direction from the transition portion 92 to the rear edge TE. The transition part 92 may be flat or curved. The curved upper and lower lamps 90, 94 and the curved transition 92 may be designed and configured using bezier splines.

  The upper and lower gradually expanding portions 102 and 103 of the variable width WV of the hole 30 maintain the outlet velocity of the refrigerant flow 52 and the gas velocity of the high-temperature combustion gas along the outer surface 43 of the positive pressure side wall 42 at the blowing portion. And minimize the resulting negative effects of aerodynamic losses and turbine efficiency.

  In FIGS. 13 and 14, an alternative constant area inlet 70 is shown. The alternative inlet 70 includes a metering portion 100 with a constant width W and a constant height H. The metering unit 100 has a flow cross section 74 with a constant area. The measuring unit 100 has a first length L1 extending in the downstream direction. Downstream of the metering unit 100 is a gradually expanding inlet 108 as shown in FIG. As shown in FIG. 3, the front end of the in-hole partition wall 68 includes an upper portion spaced apart in the blade length direction leading to the tail end or the downstream end 110 of the gradually expanding inlet portion 108 and the upper and lower gradually expanding portions 102 and 103, respectively. The lower inlet channels 112 and 114 are separated or divided.

  As shown in FIG. 3, the first length L1 extending in the downstream direction of the metering unit 100 is a fluid diameter Dh = (4 * A) / P, where A is the flow area and P is the metering unit 100. The “wet” edge of the flow area. The metering part 100 shown here has a preferred first length L1 equal to up to 1.5 times the fluid diameter (1.5 * Dh).

  The invention has been described in an illustrative manner. Of course, the terminology used is intended to be more of a descriptive term than a limiting term. While what has been described herein is considered to be a preferred exemplary embodiment of the present invention, other modifications of the present invention will be apparent to those skilled in the art from the teachings herein, and thus the original spirit of the present invention. All such modifications that fall within the scope and range of interest are desired to be assured by the appended claims.

  Accordingly, what is desired to be secured by US Patent is the invention as defined and differentiated in the following claims.

8 Central axis 10 High-pressure turbine stage 12 Turbine blade 14 Blade base 16 Axial insertion dovetail 17 Support rotor disk 18 Pressurized air 19 High-temperature combustion gas 20 Combustor 22 High-pressure turbine (HPT)
24 Low pressure turbine (LPT)
28 Turbine nozzle 30 Trailing edge cooling hole 32 High pressure turbine blade 34 Blade base 36 Blade tip 38 Row of trailing edge cooling holes 39 Pressure side wall surface 40 Negative pressure side wall surface 42 Pressure side wall 43 Outer surface 44 Negative pressure side wall 46 Upper hole surface 48 Lower hole Surface 49 Blowing lip 50 Flat portion 51 Slot floor 52 Pressurized cooling air or refrigerant flow 54 Internal cooling cavity or circuit 56 Thin trailing edge 58 Blowing portion 60 Slot surface 62 Round portion 64 Slot corner 66 Trailing edge cooling slot 68 Inlet partition 69 downstream end 70 taper gradually increasing inlet 72 front end 73 base diameter 74 flow section 75 rectangular portion 78 quarter side 80 hole interval wall 82 inner end portion 84 outer end portion 88 deep floor 90 upper ramp 92 transition portion 94 lower ramp 100 measuring portion 102 Upper gradually expanding part 103 Lower gradually expanding part 104 Throat part 106 Tapered inlet part 108 Gradually expanding inlet part 1 0 Tail or downstream end 112 Upper inlet flow path 114 Lower inlet flow path 116 Tail end A Flow area A1, A2 Gradation angle A3 Flat part angle C Chord direction D Downstream direction H Height L1, L2, L3 Length LE Previous Edge P Wet edge R Corner radius RF Round radius RB Upper corner radius RT Bottom corner radius S Blade length TE Trailing edge W Width WV Variable width

Claims (29)

A pressure side wall (42) and a pressure side wall (44) which are spaced apart in the width (W) direction and extend outward along the blade length (S) from the blade base (34) to the blade tip (36), and are opposed to each other. A pressure side wall (42) and a suction side wall (44) extending in a chord direction (C) between a leading edge (LE) and a trailing edge (TE);
It is a row (38) in the blade length direction of branched trailing edge cooling holes (30) separated in the blade length (S) direction, and is accommodated in the pressure side wall (42), and substantially includes the trailing edge ( A lengthwise row (38) of trailing edge cooling holes (30) extending in the chord direction (C) to TE and terminating in a corresponding trailing edge cooling slot (66) spaced in the length (S) direction; ,
A hole interval wall (80) extending in the axial direction separating the cooling holes (30) from each other in the blade length (S) direction, wherein each of the cooling holes (30) is adjacent to the hole interval wall (80). A hole spacing wall (80) including an inlet (70) between the pair, the inlet (70) including a gradual inlet portion (108);
An axial bore partition wall (68) extending in the downstream direction (D) toward the trailing edge (TE), the blade length in the downstream direction (D) and the tail direction of the gradually expanding inlet portion (108) An in-hole partition wall (68) that branches the cooling hole (30) into an upper gradually expanding portion (102) and a lower gradually expanding portion (103) that are separated in the (S) direction and gradually expand in the blade length (S) direction;
The front end of the intra-hole partition wall (68), the tail end or the downstream end (110) of the gradually expanding inlet portion (108) is connected to the upper gradually expanding portion (102) and the lower gradually expanding portion (103). The upper inlet channel (112) and the lower inlet channel (114) separated in the blade length (S) direction leading to each are separated or divided, and the upper gradual expansion of each of the cooling holes (30) A front end of the in-hole partition wall (68), wherein the portion (102) and the lower gradually expanding portion (103) communicate with a corresponding slot of the trailing edge cooling slot (66);
A turbine blade (12) of a gas turbine engine comprising:   The height (H) in the blade length (S) direction that is substantially larger than the hole width (W) through the upper gradual expansion portion (102) and the lower gradual expansion portion (103). Wings (12).   Each of the pressure side wall (42) and the pressure side wall (44) further includes a pressure side wall surface (39) and a pressure side wall surface (40) in the hole (30), and the pressure side wall surface (39) is provided. The wing (12) of claim 2, wherein the wing (12) is planar throughout the upper gradual expansion (102) and the lower gradual expansion (103).   The wing (12) according to claim 3, further comprising a constant width (W) through the upper gradual expansion (102) and the lower gradual expansion (103).   A flat portion (50), and the flat portion (50) is disposed between adjacent slots in the blade length (S) direction of the trailing edge cooling slot (66), and the slot floor (51) is provided. The blade (12) of claim 4, wherein the blade (12) is disposed in the trailing edge cooling slot (66) between the flats (50).   The wing (12) according to claim 5, further comprising the flat part (50) inclined away from the outer surface (43) at a flat part angle (A3) in the range of 0-5 degrees.   The wing of claim 5, further comprising the flat portion (50) coplanar with or coplanar with the outer surface (43) of the pressure sidewall (42) around each of the cooling slots (66). (12).   Said inlet (70) being a tapered progressive inlet (70) comprising a tapered inlet part (106), a throat (104) and said progressive inlet part (108) in relation to a continuous flow in the downstream direction (D) The wing (12) of claim 1, further comprising: A height (H) in the blade length (S) direction that is substantially larger than a hole width (W) through the upper gradually expanding portion (102) and the lower gradually expanding portion (103);
The pressure side wall surface (39) and the suction side wall surface (40) of the pressure side wall (42) and the suction side wall (44) in the hole (30), respectively, the pressure side wall surface (39) being A pressure side wall surface (39) and a pressure side wall surface (40) that are planar throughout the upper gradual expansion portion (102) and the lower gradual expansion portion (103);
A constant width (W) through the upper gradual expansion portion (102) and the lower gradual expansion portion (103);
Of the trailing edge cooling slots (66), flat portions (50) disposed between slots adjacent in the blade length (S) direction, and the trailing edge cooling slots (66) between the flat portions (50). Slot floor (51) arranged in
The wing (12) of claim 8, further comprising:   The blade according to claim 9, further comprising the flat portion (50) coplanar with or coplanar with the outer surface (43) of the pressure sidewall (42) around each of the cooling slots (66). (12).   Each of the upper gradual expansion portion (102) and the lower gradual expansion portion (103) and the trailing edge that gradually expand at different first and second gradual expansion angles (A1) and (A2), respectively. The wing (12) of claim 10, further comprising a corresponding one of the cooling slots (66). Each of the upper gradually expanding portion (102) and the lower gradually expanding portion (103) having a track-shaped flow cross section (74), wherein the track-shaped flow cross section (74) is in the blade length (S) direction. And a rounded or semi-circular inner end (82) and a rectangular portion (75) between the outer end (84) and spaced apart in the wing length (S) direction to reduce the corner radius (R). The upper gradual section (102) and the lower gradual expansion section (103) including a rounded or semi-circular inner end (82) and a rectangular section (75) between the outer end (84). Each of
A rounded portion (62) of the slot corner (64) between the flat portion (50) and the slot floor (51), which is substantially the same size as the corner radius (R) of the flow cross section (74). A round portion (62) having a round radius (RF) of
The wing (12) of claim 5, further comprising:   The blade according to claim 12, further comprising the flat portion (50) coplanar with or coplanar with the outer surface (43) of the pressure sidewall (42) around each of the cooling slots (66). (12).   The wing (12) according to claim 12, further comprising the flat part (50) inclined away from the outer surface (43) at a flat part angle (A3) in the range of 0-5 degrees.   Each of the upper gradual expansion portion (102) and the lower gradual expansion portion (103) and the trailing edge that gradually expand at different first and second gradual expansion angles (A1) and (A2), respectively. The wing (12) of claim 13, further comprising a corresponding one of the cooling slots (66).   Each of the upper gradual expansion portion (102) and the lower gradual expansion portion (103) and the trailing edge that gradually expand at different first and second gradual expansion angles (A1) and (A2), respectively. The wing (12) of claim 5, further comprising a corresponding one of the cooling slots (66).   The wing of claim 16, further comprising the flat portion (50) coplanar with or coplanar with the outer surface (43) of the pressure sidewall (42) around each of the cooling slots (66). (12).   The wing (12) of claim 16, further comprising the flat portion (50) inclined away from the outer surface (43) at a flat portion angle (A3) in the range of 0-5 degrees.   At least one of the cooling holes (30), through at least a part of each of the gradually expanding upper gradually expanding part (102) and the lower gradually expanding part (103) of the corresponding cooling slot (66). It includes a deepening floor (88) extending in the downstream direction at least partially through the cooling slot therein, wherein the deepening floor (88) is in a progressive relationship in the downstream direction (D) with the gradually expanding portion (102, 103). A flat upper ramp (90), a flat lower ramp (94) in the trailing edge cooling slot (66), and a transition (92) between the upper ramp (90) and the lower ramp (94). The upper ramp (90) is inclined upward from the suction side wall surface (40) and extends in the downstream direction (D), and the lower ramp (94) is inclined downward from the transition portion (92). Edge (T ) Extending in a downstream direction (D) until further comprises at least one of said cooling holes (30), blade according to claim 5 (12).   The blade according to claim 19, further comprising the flat portion (50) coplanar with or coplanar with the outer surface (43) of the pressure sidewall (42) around each of the cooling slots (66). (12).   Said inlet (70) being a tapered progressive inlet (70) comprising a tapered inlet part (106), a throat (104) and said progressive inlet part (108) in relation to a continuous flow in the downstream direction (D) The wing (12) of claim 20, further comprising: A height (H) in the blade length (S) direction that is substantially larger than a hole width (W) through the upper gradually expanding portion (102) and the lower gradually expanding portion (103);
The pressure side wall surface (39) and the pressure side wall surface (40) of the pressure side wall (42) and the suction side wall (44) in the hole (30), respectively, wherein the pressure side wall surface (42) is A pressure side wall surface (39) and a pressure side wall surface (40) that are planar throughout the upper gradual expansion portion (102) and the lower gradual expansion portion (103);
A constant width (W) through the upper gradual expansion portion (102) and the lower gradual expansion portion (103);
Of the trailing edge cooling slots (66), flat portions (50) disposed between slots adjacent in the blade length (S) direction, and the trailing edge cooling slots (66) between the flat portions (50). Slot floor (51) arranged in
The wing (12) of claim 21, further comprising:   Each of the upper gradual expansion portion (102) and the lower gradual expansion portion (103) and the trailing edge that gradually expand at different first and second gradual expansion angles (A1) and (A2), respectively. The wing (12) of claim 22, further comprising a corresponding one of the cooling slots (66).   The inlet (70), which is an inlet having a constant area upstream of the gradually expanding inlet (108), has a first length (L1) extending in the downstream direction (D), and has a constant area (A). An inlet having a constant width (W) and a constant height (H) throughout the first length (L1). The wing (12) of claim 1, further comprising (70). A height (H) in the blade length (S) direction that is substantially larger than a hole width (W) through the upper gradually expanding portion (102) and the lower gradually expanding portion (103);
The pressure side wall surface (39) and the suction side wall surface (40) of the pressure side wall (42) and the suction side wall (44) in the hole (30), respectively, the pressure side wall surface (39) being A pressure side wall surface (39) and a pressure side wall surface (40) that are planar throughout the upper gradual expansion portion (102) and the lower gradual expansion portion (103);
A constant width (W) through the upper gradual expansion portion (102) and the lower gradual expansion portion (103);
Of the trailing edge cooling slots (66), flat portions (50) disposed between slots adjacent in the blade length (S) direction, and the trailing edge cooling slots (66) between the flat portions (50). Slot floor (51) arranged in
The wing (12) of claim 24, further comprising:   26. The wing of claim 25, further comprising the flat portion (50) coplanar with or coplanar with the outer surface (43) of the pressure sidewall (42) around each of the cooling slots (66). (12).   26. A wing (12) according to claim 25, further comprising the flat part (50) inclined away from the outer surface (43) at a flat part angle (A3) in the range of 0-5 degrees.   Each of the upper gradual expansion portion (102) and the lower gradual expansion portion (103) gradually expanding at different first gradual expansion angles (A1) and second gradual expansion angles (A2), respectively, and the rear 27. The wing (12) of claim 26, further comprising a corresponding one of the edge cooling slots (66). Each of the upper gradually expanding portion (102) and the lower gradually expanding portion (103) having a track-shaped flow cross section (74), wherein the track-shaped flow cross section (74) is in the blade length (S) direction. And a rounded or semi-circular inner end (82) and a rectangular portion (75) between the outer end (84) and spaced apart in the wing length (S) direction to reduce the corner radius (R). The upper gradual section (102) and the lower gradual expansion section (103) including a rounded or semi-circular inner end (82) and a rectangular section (75) between the outer end (84). Each of
A rounded portion (62) of the slot corner (64) between the flat portion (50) and the slot floor (51), which is substantially the same size as the corner radius (R) of the flow cross section (74). A round portion (62) having a round radius (RF) of
The wing (12) of claim 28, further comprising: