Abstract:
Disclosed herein is a method comprising injecting into a thin wall disposable core die a slurry having a viscosity of about 1 to about 1,000 Pascal-seconds at room temperature when tested at a shear rate of up to 70 seconds−1 and a flow index of less than 0.6 at a pressure of up to about 7 kilograms-force per square centimeter; wherein the thin wall disposable core die has an average wall thickness of about 1.5 to about 10 millimeters; curing the slurry to form a cured ceramic core; removing the thin wall disposable core die from the cured ceramic core; and firing the cured ceramic core to form a solidified ceramic core.
Abstract:
A shroud assembly is provided for a gas turbine engine that has a temperature at a hot operating condition substantially greater than at a cold assembly condition thereof. The shroud assembly includes: at least one arcuate shroud segment adapted to surround a row of rotating turbine blades which has an arcuate, axially extending mounting flange; a shroud hanger having an arcuate, axially-extending hook disposed in mating relationship to the mounting flange; and an arcuate C-clip having inner and outer arms overlapping the hook and the mounting flange. The curvatures of the mounting flange and the inner arm of the C-clip are selected so as to define a matched interface therebetween. Their curvatures are substantially greater that the curvature of the hook.
Abstract:
A stator vane that may be used in engine assemblies. The stator vane includes an airfoil having a first sidewall and a second sidewall that is coupled to the first sidewall at a leading edge and at a trailing edge. The airfoil extends radially from a root portion to a tip portion. Each of the leading and trailing edges includes at least one lean directional change and a plurality of sweep directional changes that are defined between the root portion and the tip portion.
Abstract:
Disclosed herein is a composite core die comprising a reusable core die; and a disposable core die; wherein the disposable core die is in physical communication with the reusable core die; and further wherein surfaces of communication between the disposable core die and the reusable core die serve as barriers to prevent the leakage of a slurry that is disposed in the composite core die.
Abstract:
An downstream plasma boundary layer shielding system includes film cooling apertures disposed through a wall having cold and hot surfaces and angled in a downstream direction from a cold surface of the wall to an outer hot surface of the wall. A plasma generator located downstream of the film cooling apertures is used for producing a plasma extending downstream over the film cooling apertures. Each plasma generator includes inner and outer electrodes separated by a dielectric material disposed within a groove in the outer hot surface. The wall may be part of a hollow airfoil or an annular combustor or exhaust liner. A method for operating the downstream plasma boundary layer shielding system includes forming a plasma extending in the downstream direction over the film cooling apertures along the outer hot surface of the wall. The method may further include operating the plasma generator in steady state or unsteady modes.
Abstract:
A method for cooling a turbine shroud assembly includes providing a turbine shroud assembly including a shroud segment having a leading edge, a trailing edge and a midsection defined therebetween. A shroud support circumferentially spans and supports the shroud segment. The shroud support includes a forward hanger coupled to the leading edge, a midsection hanger coupled to the midsection and an aft hanger coupled to the trailing edge. An annular shroud ring structure includes a midsection position control ring coupled to the midsection hanger and an aft position control ring coupled to the aft hanger. Cooling air is extracted from a compressor positioned upstream of the turbine shroud assembly. Cooling air is metered through the shroud support directly into only at least one active convection cooling zone defined between the shroud segment and the shroud support while substantially preventing cooling air from entering an inactive convection cooling zone positioned radially outwardly from the at least one active convection cooling zone and defined between the shroud support and the shroud ring structure and between the midsection position control ring and the aft position control ring.
Abstract:
A method of assembling a gas turbine engine is provided. The method includes coupling at least one turbine nozzle segment within the gas turbine engine. The at least one turbine nozzle segment includes at least one airfoil vane extending between an inner band and an outer band that includes an aft flange and a radial inner surface. The method also includes coupling at least one turbine shroud segment downstream from the at least one turbine nozzle segment, wherein the at least one turbine shroud segment includes a leading edge and a radial inner surface, and coupling a cooling fluid source in flow communication with the at least one turbine nozzle segment such that cooling fluid channeled to each turbine nozzle outer band aft flange is directed at an oblique discharge angle towards the leading edge of the at least one turbine shroud segment.
Abstract:
A method for assembling a gas turbine engine is provided. The method includes providing a turbine nozzle including an outer band and an inner band, wherein each band includes a leading edge, a trailing edge, and a body extending therebetween. At least one of the outer band and the inner band has at least one radial tab extending outward therefrom. The method also includes coupling at least one seal between at least one of the radial tabs extending from the outer band and the inner band and a respective leading edge of the outer and inner band. The method also includes positioning at least one non-planar seal support against at least one portion of the seal.
Abstract:
A turbine blade includes an airfoil, platform, shank, and dovetail integrally joined together. A cooling chamber is located under the platform and has a portal exposed outwardly from the shank. A damper seat surrounds the portal and is recessed under the platform for receiving a vibration damper to sealingly close the chamber across the portal.
Abstract:
A method facilitates the assembly of a gas turbine engine. The method of assembly comprises providing a turbine nozzle including an inner band, an outer band, at least one vane extending between the inner and outer bands, and at least one leading edge fillet extending between the at least one vane and at least one of the inner and outer bands, wherein a leading edge of the at least one vane is downstream from the leading edges of the inner and outer bands, and coupling the turbine nozzle within the gas turbine engine such that the leading edge fillet is configured to facilitate minimizing vortex formation along the vane leading edge adjacent at least one of the inner and outer bands.