Abstract:
A gas turbine engine combustion system includes a plurality of fuel injectors circumferentially disposed around a combustor in a one to one fuel supply relationship with a plurality of fuel nozzle valves, and an electronic controller for controlling the fuel nozzle valves to eliminate and/or reduce hot streaking in response to sensed hot streak conditions. The fuel nozzle valves may be modulating valves. The electronic controller may be used to individually control the fuel nozzle valves. The hot streak conditions may be sensed with temperature sensors such as temperature sensors operably mounted in the combustor. A program in the electronic controller may be used for determining broken or malfunctioning sensors by calculating a combustor temperature and comparing it to measured temperatures from the sensors and comparing the measured fuel pressures in the individual fuel nozzle circuits with the simulated or calculated fuel pressures.
Abstract:
A method of assembling a gas turbine engine includes coupling a turbine shroud assembly within the gas turbine engine. The turbine shroud assembly includes a shroud segment having a leading edge defining a forward face and a radial inner surface. A turbine nozzle is coupled to the turbine shroud assembly such that a gap is defined between an aft face of an outer band of the turbine nozzle and the forward face. A plurality of recuperated cooling openings are defined through the leading edge at an oblique inlet angle with respect to a centerline of the gap and between the forward face and the radial inner surface to direct cooling fluid through the leading edge to facilitate preferential cooling of the leading edge.
Abstract:
A method for cooling a shroud segment of a gas turbine engine is provided. The method includes providing a turbine shroud assembly including a shroud segment having an inner surface and a leading edge that is substantially perpendicular to the inner surface, and coupling a turbine nozzle to the turbine shroud segment such that a gap is defined between an aft edge of an outer band of the turbine nozzle and the leading edge. The method also includes directing cooling air into the gap, and directing the cooling air in the gap through at least one cooling hole extending between the leading edge and the inner surface.
Abstract:
A turbine stage includes a stator nozzle having a row of vanes mounted between inner and outer bands. The inner band terminates in an ovate ledge converging aft from the vanes with radially outer and inner convex surfaces joined at a convex apex. The ovate ledge reduces aerodynamic losses at the rotary seal with a row of following turbine rotor blades.
Abstract:
A hollow turbine airfoil includes a tip cap bounding an internal cooling circuit between opposite pressure and suction sidewalls. The tip cap includes an internal dome surrounding a dust hole, and the dome is inclined inwardly toward the airfoil root both transversely between the opposite sidewalls and chordally between opposite leading and trailing edges of the airfoil.
Abstract:
A gas turbine engine shroud includes a row of different first and second shroud segments alternating circumferentially therearound. The first segments have a first pattern of first cooling holes extending therethrough. The second segments have a second pattern of second cooling holes extending therethrough. The corresponding patterns have different collective flowrate capabilities.
Abstract:
A turbofan engine includes a fan, compressor, combustor, single-stage high pressure turbine, and low pressure turbine joined in serial flow communication. First stage rotor blades in the low pressure turbine are oriented oppositely to the rotor blades in the high pressure turbine for counterrotation. First stage stator vanes in the low pressure turbine have camber and twist for carrying swirl directly between the rotor blades of the high and low pressure turbines.
Abstract:
A turbine nozzle includes first and second vanes joined to outer and inner bands. The vanes include outboard sides defining outboard flow passages containing axial splitlines, and opposite inboard sides defining an inboard flow passage without axial splitline. The two vanes include different cooling circuits for differently cooling the inboard and outboard vane sides.
Abstract:
A synthetic model of a component is created from a 3-D numerical model thereof. A core is then cast inside the synthetic model. The synthetic model may then be removed from the cast core, and then the cast core is used for casting an authentic component therearound. The core is removed from inside the authentic component, which authentic component precisely matches the original synthetic model therefor.
Abstract:
A casting core for a turbine blade includes a plurality of rods extending above a shank. The rods define internal cooling channels in the airfoil of the blade, and the shank defines an inlet channel in the dovetail of the blade. A plurality of stubs are clustered together at a bulb joined to the shank and radiate outwardly to integrally join different ones of the rods for increasing strength of the core.