Abstract: Flow path assemblies and methods for assembling a flow path assembly of a gas turbine engine are provided. For example, a flow path assembly comprises a unitary outer wall including combustor and turbine portions that are integrally formed as a single unitary structure; a single piece, generally annular inner band; and a plurality of nozzle airfoils extending from the unitary outer wall to the inner band. Each nozzle airfoil interfaces with the inner band to position the inner band within the assembly. An exemplary assembly method comprises inserting an inner band into a flow path having a unitary outer wall as its outer boundary; inserting a plurality of nozzle airfoils into the flow path; and securing the nozzle airfoils with respect to the unitary outer wall. The inner band interfaces with an inner end of each nozzle airfoil to radially locate the inner band within the flow path.

Abstract: Flow path assemblies for gas turbine engines are provided. For example, a flow path assembly comprises an inner wall defining an inner boundary of a flow path and a plurality of pockets therein, and a unitary outer wall defining an outer boundary of the flow path. The unitary outer wall includes combustor and turbine portions that are integrally formed as a single unitary structure. The flow path assembly further comprises a plurality of nozzle airfoils that each have an inner end radially opposite an outer end and define an internal cavity for receipt of a flow of cooling fluid. The inner end of each nozzle airfoil is received in one of the plurality of inner wall pockets and defines an outlet for the flow of cooling fluid to flow from the internal cavity to the pocket, which forms a fluid curtain to discourage fluid leakage from the flow path.

Abstract: Flow path assemblies of gas turbine engines are provided. For example, a flow path assembly comprises an inner wall and a unitary outer wall that includes a combustor portion extending through a combustion section of the gas turbine engine and a turbine portion extending through at least a first turbine stage of a turbine section of the gas turbine engine. The combustor portion and the turbine portion are integrally formed as a single unitary structure. The flow path assembly further comprises a plurality of nozzle airfoils, each nozzle airfoil having an inner end radially opposite an outer end. The inner wall or the unitary outer wall defines a plurality of openings therethrough, and each opening is configured for receipt of one of the plurality of nozzle airfoils. Methods of assembling flow path assemblies also are provided.

Abstract: A ceramic matrix composite article includes a chemical vapor infiltration ceramic matrix composite base portion including ceramic fiber reinforcement material in a ceramic matrix material having between 0% and 5% free silicon. The ceramic matrix composite article further includes a melt infiltration ceramic matrix composite covering portion including a ceramic fiber reinforcement material in a ceramic matrix material having a greater percentage of free silicon than the chemical vapor infiltration ceramic matrix composite base portion.

Abstract: Turbine nozzle sections and airfoils having trailing edge segments are provided. In one embodiment, a turbine nozzle section comprises an inner band defining a pocket; an outer band defining an opening therethrough; and an airfoil radially extending from the inner band to the outer band and including pressure and suction sides. The airfoil has a body segment including a cavity and a plurality of ejector apertures defining a passageway from the cavity to an outer surface of the airfoil, and a trailing edge segment including an inner end and an outer end. The body segment defines a projection projecting inwardly from the suction side, and the trailing edge segment defines a notch opening toward the suction side. The projection is received within the notch. The inner end of the trailing edge segment is received within the inner band pocket, and the outer end is positioned within the outer band opening.

Abstract: Flow path assemblies of gas turbine engines are provided. For example, a flow path assembly comprises an inner wall and a unitary outer wall that includes a combustor portion extending through a combustion section of the gas turbine engine and a turbine portion extending through at least a first turbine stage of a turbine section of the gas turbine engine. The combustor portion and the turbine portion are integrally formed as a single unitary structure. The flow path assembly further comprises a plurality of nozzle airfoils, each nozzle airfoil having an inner end radially opposite an outer end. The inner wall or the unitary outer wall defines a plurality of openings therethrough, and each opening is configured for receipt of one of the plurality of nozzle airfoils. Methods of assembling flow path assemblies also are provided.

Abstract: Flow path assemblies for gas turbine engines are provided. For example, a flow path assembly comprises an inner wall defining an inner boundary of a flow path and a plurality of pockets therein, and a unitary outer wall defining an outer boundary of the flow path. The unitary outer wall includes combustor and turbine portions that are integrally formed as a single unitary structure. The flow path assembly further comprises a plurality of nozzle airfoils that each have an inner end radially opposite an outer end and define an internal cavity for receipt of a flow of cooling fluid. The inner end of each nozzle airfoil is received in one of the plurality of inner wall pockets and defines an outlet for the flow of cooling fluid to flow from the internal cavity to the pocket, which forms a fluid curtain to discourage fluid leakage from the flow path.

Abstract: Flow path assemblies and methods for assembling a flow path assembly of a gas turbine engine are provided. For example, a flow path assembly comprises a unitary outer wall including combustor and turbine portions that are integrally formed as a single unitary structure; a single piece, generally annular inner band; and a plurality of nozzle airfoils extending from the unitary outer wall to the inner band. Each nozzle airfoil interfaces with the inner band to position the inner band within the assembly. An exemplary assembly method comprises inserting an inner band into a flow path having a unitary outer wall as its outer boundary; inserting a plurality of nozzle airfoils into the flow path; and securing the nozzle airfoils with respect to the unitary outer wall. The inner band interfaces with an inner end of each nozzle airfoil to radially locate the inner band within the flow path.