Abstract:
A wall in a gas turbine engine includes inner and outer surfaces having a row of compound chevron film cooling holes extending therethrough. The chevron holes diverge both longitudinally and laterally between an inlet at the wall inner surface and a chevron outlet at the wall outer surface.
Abstract:
A coating and coating process for incorporating surface features on an air-cooled substrate surface of a component for the purpose of promoting heat transfer from the component. The coating process generally comprises depositing a first metallic coating material on the surface of the component using a first set of coating conditions to form a first environmental coating layer, and then depositing a second metallic coating material using a second set of coating conditions that differ from the first set, such that an outer environmental coating layer is formed having raised surface features that cause the surface of the outer environmental coating layer to be rougher than the surface of the first environmental coating layer.
Abstract:
A turbine blade includes a hollow airfoil joined to a dovetail and platform. The airfoil includes leading and trailing edge cooling circuits disposed between the opposite pressure and suction sidewalls of the airfoil along the leading and trailing edges thereof. The leading edge cooling circuit includes a radial inlet commencing in the base of the dovetail, and the trailing edge cooling circuit includes an axial inlet commencing in the aft face of the dovetail for receiving coolant having different pressure and temperature.
Abstract:
A turbine blade includes an airfoil having opposite pressure and suction sidewalls joined together at opposite leading and trailing edges and extending longitudinally from root to tip. A plurality of independent cooling circuits are disposed inside the airfoil correspondingly along the pressure and suction sidewalls thereof. Each circuit includes an inlet channel extending through the dovetail. One of the circuits includes multiple longitudinal channels separated by corresponding perforate partitions each including a row of impingement holes for cascade impingement cooling the inner surface of the airfoil.
Abstract:
A pulse detonation system for a gas turbine engine having a longitudinal centerline axis extending therethrough includes a rotatable cylindrical member having a forward surface, an aft surface, and an outer circumferential surface, where a plurality of spaced detonation passages are disposed therethrough. Each detonation passage includes at least a portion having a longitudinal axis extending therethrough oriented at a circumferential angle to the longitudinal centerline axis. The pulse detonation system further includes a shaft rotatably connected to the cylindrical member and a stator configured in spaced arrangement with the forward surface of the cylindrical member and a portion of the shaft. The stator has at least one group of ports formed therein alignable with the detonation passages as the cylindrical member rotates. In this way, detonation cycles are performed in the detonation passages so that combustion gases exit the aft surface of the cylindrical member to create a torque which causes the cylindrical member to rotate. Each detonation passage further includes a first end located adjacent the forward surface of the cylindrical member and a second end located adjacent the aft surface of the cylindrical member.
Abstract:
A turbine airfoil includes pressure and suction sidewalls extending in chord between leading and trailing edges and in span between a root and a tip. A septum is spaced between the sidewalls to define two cooling circuits on opposite sides of the septum which converge between the leading and trailing edges. An array of pins extends inwardly from the pressure sidewall at a discharge end of the circuits, and the pins decrease in length to conform with the converging circuit.
Abstract:
A turbofan engine includes in serial flow communication a first fan, second fan, multistage compressor, combustor, first turbine, second turbine, and third turbine. The first turbine is joined to the compressor by a first shaft. The second turbine is joined to the second fan by a second shaft. And, the third turbine is joined to the first fan by a third shaft. First, second, and third cooling circuits are joined to different stages of the compressor for cooling the forward and aft sides and center bore of the first turbine with different pressure air.
Abstract:
According to an embodiment of the invention, a method for repairing a coated high pressure turbine blade, which has been exposed to engine operation, to restore coated airfoil contour dimensions of the blade, is disclosed. The method comprises providing an engine run high pressure turbine blade including a base metal substrate made of a nickel-based alloy and having thereon a thermal barrier coating system. The thermal barrier coating system comprises a diffusion bond coat on the base metal substrate and a top ceramic thermal barrier coating comprising a yttria stabilized zirconia material. The top ceramic thermal barrier coating has a nominal thickness t. The method further comprises removing the thermal barrier coating system, wherein a portion of the base metal substrate also is removed, and determining the thickness of the base metal substrate removed. The portion of the base metal substrate removed has a thickness, Δt. The method also comprises reapplying the diffusion bond coat to the substrate, wherein the bond coat is reapplied to a thickness, which is about the same as applied prior to the engine operation; and reapplying the top ceramic thermal barrier coating to a nominal thickness of t+Δt, wherein Δt compensates for the portion of removed base metal substrate. Advantageously, the coated airfoil contour dimensions of the high pressure turbine blade are restored to about the coated dimensions preceding the engine run.
Abstract:
A component includes at least one wall having an inner portion and an outer portion. A number of pins extend between the inner and outer portions of the wall. The pins define a mesh cooling arrangement having a number of flow channels. A number of dimples are located in at least one of the inner and outer portions of the wall. The component may also include a number of turbulators disposed on at least one of the inner and outer portions of the wall.
Abstract:
An actively cooled TBC bond coat wherein active convection cooling is provided through micro channels inside or adjacent to a bond coat layer applied to a substrate. The micro channels communicate directly with at least one cooling fluid supply contained within a turbine engine component, thereby providing direct and efficient cooling for the bond coat layer. Because the substrate is covered with an actively cooled bond coat layer, it will reduce the cooling requirement for the substrate, thus allowing the engine to run at higher operating temperature without the need for additional cooling air, achieving a better engine performance. In one form, the component includes a substrate having at least one substrate channel with a first and second end. At least one micro channel is in fluid communication with a plenum which in turn is in fluid communication with at least one substrate channel through an exit orifice in the substrate channel which is at a first end of the substrate channel. A second end of the substrate channel is in communication with a cooling fluid supply, for example, cooling circuits contained within the turbine engine component. The micro channel is located between the substrate surface and the outer gas flow path surface of the component.