Abstract: Ceramic matrix composite airfoils for gas turbine engines are provided. In an exemplary embodiment, an airfoil includes opposite pressure and suction sides extending radially along a span. The pressure and suction sides define an outer surface of the airfoil. The airfoil further includes opposite leading and trailing edges extending radially along the span, the pressure and suction sides extending axially between the leading and trailing edges. The airfoil also includes a filler pack defining the trailing edge; the filler pack comprises a ceramic matrix composite material. Moreover, the airfoil includes a plenum defined within the airfoil for receiving a flow of cooling fluid, and a cooling passage defined within the filler pack for directing the flow of cooling fluid from the plenum to the outer surface of the airfoil. Methods for forming airfoils for gas turbine engines also are provided.

Abstract: An airfoil for a gas turbine engine is provided that includes a first portion formed from a first plurality of plies of a ceramic matrix composite material and defining an inner surface of the airfoil, as well as a second portion formed from a second plurality of plies of a ceramic matrix composite material and defining an outer surface of the airfoil. The first portion and the second portion define a non-line of sight cooling aperture extending from the inner surface to the outer surface of the airfoil. In one embodiment, a surface angle that is less than 45° is defined between a second aperture and the outer surface. A method for forming an airfoil for a gas turbine engine also is provided.

Abstract: Airfoils for gas turbine engines are provided. In one embodiment, an airfoil formed from a ceramic matrix composite material includes opposite pressure and suction sides extending radially along a span and defining an outer surface of the airfoil. The airfoil also includes opposite leading and trailing edges extending radially along the span. The pressure and suction sides extend axially between the leading and trailing edges. The leading edge defines a forward end of the airfoil, and the trailing edge defining an aft end of the airfoil. Further, the airfoil includes a trailing edge portion defined adjacent the trailing edge at the aft end of the airfoil; a plenum defined within the airfoil forward of the trailing edge portion; and a cooling passage defined within the trailing edge portion proximate the suction side. Methods for forming airfoils for gas turbine engines also are provided.

Abstract: A component for a gas turbine engine includes a first region formed substantially of a first CMC material, wherein first region defines a first thermal conductivity. The component further includes a second region formed substantially of a second CMC material, wherein the second region defines a second thermal conductivity. Further, the component defines a thickness and the first region is positioned adjacent to the second region along the thickness, wherein the first thermal conductivity is different than the second thermal conductivity to alert a thermal profile of the component.

Abstract: Shrouds and shroud segments for gas turbine engines are provided. In one embodiment, a shroud segment for a gas turbine engine having a rotor blade stage and a nozzle stage is provided. The shroud segment comprises a forward end defining an outer wall of the rotor blade stage and an aft end defining an outer wall of the nozzle stage. The aft end defines at least a portion of an opening therethrough for receipt of a nozzle, and the forward end and the aft end form a single, continuous component. In another embodiment, a gas turbine engine is provided, having a shroud with a forward end positioned near a leading edge of a plurality of rotor blades of a rotor blade stage and an aft end positioned near a trailing edge of a plurality of nozzles of a nozzle stage. Methods of assembling a gas turbine engine also are provided.

Abstract: An airfoil having a radial direction extending away from an engine axis is provided. The airfoil includes an airfoil wall having an airfoil outer surface and an airfoil inner surface, with the airfoil extending radially from a first end to a second end. The airfoil defines a cooling channel interior to the inner surface with a thickness being defined between the airfoil outer surface and the airfoil inner surface. The thickness varies in the radial direction from the first end to the second end along at least one radial cross-section of the airfoil. A turbine nozzle of a turbine engine is also provided, which may include an outer band, an inner band, and the airfoil.

Abstract: An airfoil for a gas turbine engine is provided that includes a first portion formed from a first plurality of plies of a ceramic matrix composite material and defining an inner surface of the airfoil, as well as a second portion formed from a second plurality of plies of a ceramic matrix composite material and defining an outer surface of the airfoil. The first portion and the second portion define a non-line of sight cooling aperture extending from the inner surface to the outer surface of the airfoil. In one embodiment, a surface angle that is less than 45° is defined between a second aperture and the outer surface. A method for forming an airfoil for a gas turbine engine also is provided.

Abstract: Shrouds and shroud segments for gas turbine engines are provided. In one embodiment, a shroud segment for a gas turbine engine having a rotor blade stage and a nozzle stage is provided. The shroud segment comprises a forward end defining an outer wall of the rotor blade stage and an aft end defining an outer wall of the nozzle stage. The aft end defines at least a portion of an opening therethrough for receipt of a nozzle, and the forward end and the aft end form a single, continuous component. In another embodiment, a gas turbine engine is provided, having a shroud with a forward end positioned near a leading edge of a plurality of rotor blades of a rotor blade stage and an aft end positioned near a trailing edge of a plurality of nozzles of a nozzle stage. Methods of assembling a gas turbine engine also are provided.

Abstract: Ceramic matrix composite airfoils for gas turbine engines are provided. In an exemplary embodiment, an airfoil includes opposite pressure and suction sides extending radially along a span. The pressure and suction sides define an outer surface of the airfoil. The airfoil further includes opposite leading and trailing edges extending radially along the span, the pressure and suction sides extending axially between the leading and trailing edges. The airfoil also includes a filler pack defining the trailing edge; the filler pack comprises a ceramic matrix composite material. Moreover, the airfoil includes a plenum defined within the airfoil for receiving a flow of cooling fluid, and a cooling passage defined within the filler pack for directing the flow of cooling fluid from the plenum to the outer surface of the airfoil. Methods for forming airfoils for gas turbine engines also are provided.

Abstract: A turbine blade is described herein, the turbine blade including a blade root, a blade tip, and an airfoil extending between the blade root and the blade tip. The airfoil has opposite pressure and suction sides extending between a forward leading edge and an aft trailing edge of the airfoil, and a maximum thickness located between the leading edge and the trailing edge. The blade tip includes a winglet extending laterally outward from at least one of the pressure side and the suction side from a leading point between the leading edge and the maximum thickness aftward to a trailing point between the maximum thickness and the trailing edge.

Abstract: A turbine blade is described herein, the turbine blade including a blade root, a blade tip, and an airfoil extending between the blade root and the blade tip. The airfoil has opposite pressure and suction sides extending between a forward leading edge and an aft trailing edge of the airfoil, and a maximum thickness located between the leading edge and the trailing edge. The blade tip includes a winglet extending laterally outward from at least one of the pressure side and the suction side from a leading point between the leading edge and the maximum thickness aftward to a trailing point between the maximum thickness and the trailing edge.

Abstract: Flow path assemblies and methods for forming such flow path assemblies for gas turbine engines are provided. For example, a method for assembling an airfoil with a boundary structure to form a flow path assembly is provided. The method includes machining an opening into the boundary structure. The opening is sized to receive an airfoil or other component. The method also includes machining a cutout into the boundary structure proximate the opening. A locking feature is inserted into the cutout. When the airfoil is inserted into the opening, the locking feature interlocks the airfoil with the boundary structure. To seal the airfoil with the boundary structure, the airfoil is pressed against or into the boundary structure. When the airfoil is pressed, the locking feature is compressed such that a seal is formed between the airfoil and the boundary structure to seal the flow path assembly.

Abstract: A gas turbine engine arcuate leaf seal assembly includes arcuate leaf seal extending radially and circumferentially between adjacent first and second turbine components. Upper and lower leaf seal portions of leaf seal are in radially spaced apart arcuate upper and lower grooves in the first and second turbine components respectively. The seal includes an arcuate body and a circumferential retention tab extending radially away from body and disposed in a notch in a wall of grooves. Seal may have a thickness between 3 mils and 35 mils and/or torsional stiffness between 0.015 and 0.15 lb/in. Turbine components may be radially adjacent turbine nozzle upper and lower components. The upper or lower component may be made of a ceramic matrix composite material. Annular cooling air plenum including flow cavities in inner support ring segments may be in lower component and in flow communication with hollow fairing airfoils.

Abstract: CMC components having microchannels and methods for forming microchannels in CMC components are provided. For example, a method for forming microchannels in a CMC component comprises laying up a plurality of body plies for forming a body of the CMC component; laying up a microchannel ply on the plurality of body plies that has at least one void therein for forming at least one microchannel; laying up a cover ply on the microchannel ply to define an outer layer of the CMC component; and processing the laid up body plies, microchannel ply, and cover ply to form the CMC component. In another embodiment, the method comprises applying an additive matrix to the body plies to define at least one microchannel. In still other embodiments, the method comprises machining at least one microchannel in the plurality of body plies.

Abstract: A seal assembly to seal a gas turbine hot gas path flow at an interface of a combustor liner and a downstream component, such as a stage one turbine nozzle, in a gas turbine. The seal assembly including a piston ring seal housing, defining a cavity, and a piston ring disposed within the cavity. The piston ring disposed circumferentially about the combustor liner. The piston ring is responsive to a regulated pressure to secure sealing engagement of the piston ring and outer surface of the combustor liner. The seal assembly includes at least one of one or more sectional through-slots, bumps or channel features to provide for a flow therethrough of a high-pressure (Phigh) bypass airflow exiting a compressor to the cavity. The high-pressure (Phigh) bypass airflow exerting a radial force on the piston ring.

Abstract: Features and methods for modulating a flow of cooling fluid to gas turbine engine components are provided. In one embodiment, an airfoil is provided having a flow modulation insert for modulating a flow of cooling fluid received in a cavity of a body of the airfoil. In another embodiment, a shroud is provided comprising a cooling channel for a flow of cooling fluid and an insert that varies in position to modulate the flow of cooling fluid through the cooling channel. In yet another embodiment, a method for operating a gas turbine engine having a cooling circuit for cooling one or more components of the gas turbine engine comprises increasing power provided to the engine and decreasing power provided to the engine to modulate a position of a flow modulation insert located in the cooling circuit and thereby modulate the flow of cooling fluid through the cooling circuit.

Abstract: Shrouds and shroud segments for gas turbine engines are provided. In one embodiment, a shroud segment for a gas turbine engine having a rotor blade stage and a nozzle stage is provided. The shroud segment comprises a forward end defining an outer wall of the rotor blade stage and an aft end defining an outer wall of the nozzle stage. The aft end defines at least a portion of an opening therethrough for receipt of a nozzle, and the forward end and the aft end form a single, continuous component. In another embodiment, a gas turbine engine is provided, having a shroud with a forward end positioned near a leading edge of a plurality of rotor blades of a rotor blade stage and an aft end positioned near a trailing edge of a plurality of nozzles of a nozzle stage. Methods of assembling a gas turbine engine also are provided.

Abstract: A component for a gas turbine engine includes a first region formed substantially of a first CMC material, wherein first region defines a first thermal conductivity. The component further includes a second region formed substantially of a second CMC material, wherein the second region defines a second thermal conductivity. Further, the component defines a thickness and the first region is positioned adjacent to the second region along the thickness, wherein the first thermal conductivity is different than the second thermal conductivity to alert a thermal profile of the component.

Abstract: An airfoil for a gas turbine engine is provided that includes a first portion formed from a first plurality of plies of a ceramic matrix composite material and defining an inner surface of the airfoil, as well as a second portion formed from a second plurality of plies of a ceramic matrix composite material and defining an outer surface of the airfoil. The first portion and the second portion define a non-line of sight cooling aperture extending from the inner surface to the outer surface of the airfoil. In one embodiment, a surface angle that is less than 45° is defined between a second aperture and the outer surface. A method for forming an airfoil for a gas turbine engine also is provided.

Abstract: Airfoils for gas turbine engines are provided. In one embodiment, an airfoil formed from a ceramic matrix composite material includes opposite pressure and suction sides extending radially along a span and defining an outer surface of the airfoil. The airfoil also includes opposite leading and trailing edges extending radially along the span. The pressure and suction sides extend axially between the leading and trailing edges. The leading edge defines a forward end of the airfoil, and the trailing edge defining an aft end of the airfoil. Further, the airfoil includes a trailing edge portion defined adjacent the trailing edge at the aft end of the airfoil; a plenum defined within the airfoil forward of the trailing edge portion; and a cooling passage defined within the trailing edge portion proximate the suction side. Methods for forming airfoils for gas turbine engines also are provided.