Abstract:
A gas turbine engine airfoil includes first and second sidewalls joined together at opposite leading and trailing edges and spaced apart from each other to define at least one internal flow channel for channeling cooling air therein. A plenum is defined by an inner surface of the first sidewall and by an internal wall adjoining the flow channel. A pair of injection holes extend through the internal wall to feed the cooling air into the plenum. A plurality of film cooling holes extend through the first sidewall in flow communication with the plenum for channeling the cooling air in a film along an outer surface of the first sidewall to effect film cooling. The injection holes are aligned to converge toward each other so that cooling air jets discharged therefrom collide with each other inside the plenum to reduce pressure thereof. This regulates the pressure across the film cooling holes to improve film cooling.
Abstract:
A turbine airfoil has a mesh cooling hole arrangement which includes first and second pluralities of cooling holes extending between internal and external surfaces of an airfoil side wall at least at a pressure side and extending from an internal chamber to the airfoil exterior. The cooling holes of each plurality extend generally parallel to one another. The cooling holes of the first and second pluralities intersect so as to define a plurality of spaced apart internal solid nodes in the side wall having pairs of opposite sides interconnected by pairs of opposite corners. The spaced nodes define a multiplicity of hole portions of the cooling holes which extend between and along opposite sides of adjacent nodes and a plurality of flow intersections which interconnect the hole portions of the cooling holes and are disposed between the corners of adjacent nodes. The sides of the nodes have lengths which are greater than the widths of the hole portions between adjacent nodes such that, when cooling fluid is passed through the cooling holes, jet flow actions are created through the hole portions which in turn generate jet interactions at the flow intersections to cause restriction of air flow and produce a pressure drop. Also, the cooling holes have flow inlets at the internal surface and flow outlets at the external surface of the airfoil side wall. The area of the flow inlets is substantially less than the area of the flow outlets.
Abstract:
An aft entry system in a gas turbine engine is provided for cooling selected one or more of aft high and low pressure turbine stages of the engine. The aft entry system includes an air flow circuit for routing low pressure cooling air radially outward from an interstage region of a multi-stage compressor of a core engine of the gas turbine engine and axially in an aft direction to a plurality of radial passages, such as provided by stationary stator and outlet guide vanes, which provide an aft entry region to the selected high and low pressure turbine stages. The pressure of the cooling air routed by the air flow circuit of the aft entry system can be lower than the pressure of air at a discharge end of the compressor but higher than the pressure of the gas stream discharging from the selected turbine stage.
Abstract:
A method of forming an airfoil (12), including: abutting end faces (72) of cantilevered film hole protrusions (64) extending from a ceramic core (50) against an inner surface (80) of a wax die (68) to hold the ceramic core in a fixed positional relationship with the wax die; casting an airfoil including a superalloy around the ceramic core; and machining film cooling holes (34) in the airfoil after the casting step to form an pattern of film cooling holes comprising the film cooling holes formed by the machining step and the cast film cooling holes (102) formed by the film hole protrusions during the casting step.
Abstract:
A cooling passage defined between first and second spaced apart sidewalls of a turbine engine component includes a turbulator system including a plurality of rows of turbulator members. Each row includes a first side turbulator member extending from the first sidewall, and a second side turbulator member extending from the second sidewall. The first and second side turbulator members are arranged such that a space is defined therebetween. The first and second side turbulator members are staggered with respect to one another such that respective forward and aft ends thereof are offset from one another. Each row further includes at least one elongate intermediate turbulator member located at least partially in the space between the respective first and second side turbulator members.
Abstract:
A ducting arrangement (10) for a can annular gas turbine engine, including: a duct (12, 14) disposed between a combustor (16) and a first row of turbine blades and defining a hot gas path (30) therein, the duct (12, 14) having raised geometric features (54) incorporated into an outer surface (80); and a flow sleeve (72) defining a cooling flow path (84) between an inner surface (78) of the flow sleeve (72) and the duct outer surface (80). After a cooling fluid (86) traverses a relatively upstream raised geometric feature (90), the inner surface (78) of the flow sleeve (72) is effective to direct the cooling fluid (86) toward a landing (94) separating the relatively upstream raised geometric feature (90) from a relatively downstream raised geometric feature (94).
Abstract:
A seal assembly between a disc cavity and a turbine section hot gas path includes a stationary vane assembly and a rotating blade assembly downstream from the vane assembly and including a plurality of blades that are supported on a platform and rotate with a turbine rotor and the platform during operation of the engine. The platform includes a radially outwardly facing first surface, a radially inwardly facing second surface, a third surface, and a plurality of grooves extending into the third surface. The grooves are arranged such that a space is defined between adjacent grooves. During operation of the engine, the grooves guide purge air out of the disc cavity toward the hot gas path such that the purge air flows in a desired direction with reference to a direction of hot gas flow through the hot gas path.
Abstract:
A cast ceramic core (110), including: an airfoil portion (116) shaped to define an inner surface (56) of an airfoil (52) of a vane segment (50); and a shell portion (122) having a backside-shaping surface (120) shaped to define a backside surface (68) of a shroud (62) of the vane segment. The backside-shaping surface has a higher elevation (132) and a lower elevation (134). The higher elevation is set apart from a nearest point (138) on the airfoil portion by the lower elevation. The airfoil portion and the shell portion are cast as a monolithic body during a single casting pour.
Abstract:
A cooling channel (36, 36B, 63-66) cools inner surfaces (48, 50) of exterior walls (41, 43) of a component (20, 60). Interior side surfaces (52, 54) of the channel converge to a waist (W2), forming an hourglass shaped transverse profile (46). The inner surfaces (48, 50) may have fins (44) aligned with the coolant flow (22). The fins may have a transverse profile (56A, 56B) highest at mid-width of the inner surfaces (48, 50). Turbulators (92) may be provided on the side surfaces (52, 54) of the channel, and may urge the coolant flow toward the inner surfaces (48, 50). Each turbulator (92) may have a peak (97) that defines the waist of the cooling channel. Each turbulator may have a convex upstream side (93). These elements increase coolant flow in the corners (C) of the channel to more uniformly and efficiently cool the exterior walls (41, 43).
Abstract:
An outer rim seal arrangement (10), including: an annular rim (70) centered about a longitudinal axis (30) of a rotor disc (31), extending fore and having a fore-end (72), an outward-facing surface (74), and an inward-facing surface (76); a lower angel wing (62) extending aft from a base of a turbine blade (22) and having an aft end (64) disposed radially inward of the rim inward-facing surface to define a lower angel wing seal gap (80); an upper angel wing (66) extending aft from the turbine blade base and having an aft end (68) disposed radially outward of the rim outward-facing surface to define a upper angel wing seal gap (80, 82); and guide vanes (100) disposed on the rim inward-facing surface in the lower angel wing seal gap. Pumping fins (102) may be disposed on the upper angel wing seal aft end in the upper angel wing seal gap.