Abstract: A flow path assembly for a gas turbine engine is provided. The flow path assembly may include an outer casing comprising a metal material having a first coefficient of thermal expansion, a ceramic structure comprising a ceramic material having a second coefficient of thermal expansion, and a mounting component attached on a first end to the outer casing and attached on a second end to the ceramic structure. The mounting component may be constructed from at least two materials transitioning from the first end to the second end such that the coefficient of thermal expansion is different at the first end than the second end.

Abstract: A flow path assembly for a gas turbine engine is provided. The flow path assembly may include an outer casing comprising a metal material having a first coefficient of thermal expansion, a ceramic structure comprising a ceramic material having a second coefficient of thermal expansion, and a mounting component attached on a first end to the outer casing and attached on a second end to the ceramic structure. The mounting component may be constructed from at least two materials transitioning from the first end to the second end such that the coefficient of thermal expansion is different at the first end than the second end.

Abstract: Flow path assemblies and methods for forming such flow path assemblies for gas turbine engines are provided. For example, a flow path assembly for a gas turbine engine has a boundary structure, an airfoil, and a locking feature. The boundary structure and the airfoil are formed from a composite material. The boundary structure defines an opening and a cutout proximate the opening, and the airfoil is sized to fit within the opening of the boundary structure. The locking feature is received within the cutout defined by the boundary structure to interlock the airfoil with the boundary structure.

Abstract: Combustor dome assemblies having combustor deflectors are provided. For example, a combustor dome assembly comprises a combustor dome defining an opening; a ceramic matrix composite (CMC) deflector positioned adjacent the combustor dome on an aft side of the assembly; a fuel-air mixer defining a groove about an outer perimeter thereof; and a seal plate including a key. The CMC deflector includes a cup extending forward through the opening in the combustor dome that defines one or more bayonets and a slot. The bayonets are received in the fuel-air mixer groove, and the seal plate key is received in the CMC deflector slot. In another embodiment, where the seal plate may be omitted, a spring is positioned between the fuel-air mixer and the CMC deflector to hold the CMC deflector in place with respect to the combustor dome. Methods of assembling combustor dome assemblies having CMC deflectors also are provided.

Abstract: Flow path assemblies having features for positioning the assemblies within a gas turbine engine are provided. For example, a flow path assembly comprises an inner wall and a unitary outer wall that includes an integral combustion portion and turbine portion, the combustor portion extending through a combustion section of the gas turbine engine and the turbine portion extending through at least a first turbine stage of a turbine section of the gas turbine engine. The flow path assembly further comprises at least two positioning members for radially centering the flow path assembly within the gas turbine engine. The positioning members extend to the flow path assembly from one or more structures external to the flow path assembly, constrain the flow path assembly tangentially, and allow radial and axial movement of the flow path assembly. Other embodiments for positioning flow path assemblies also are provided.

Abstract: Combustor dome assemblies having combustor deflectors are provided. For example, a combustor dome assembly comprises a combustor dome defining an opening; a ceramic matrix composite (CMC) deflector positioned adjacent the combustor dome on an aft side of the assembly; a fuel-air mixer defining a groove about an outer perimeter thereof; and a seal plate including a key. The CMC deflector includes a cup extending forward through the opening in the combustor dome that defines one or more bayonets and a slot. The bayonets are received in the fuel-air mixer groove, and the seal plate key is received in the CMC deflector slot. In another embodiment, where the seal plate may be omitted, a spring is positioned between the fuel-air mixer and the CMC deflector to hold the CMC deflector in place with respect to the combustor dome. Methods of assembling combustor dome assemblies having CMC deflectors also are provided.

Abstract: Gas turbine engines, as well as outer walls and flow path assemblies of gas turbine engines, are provided. For example, an outer wall of a flow path comprises a combustor portion extending through a combustion section, and a turbine portion extending through at least a first turbine stage of a turbine section. The combustor and turbine portions are integrally formed as a single unitary structure that defines an outer boundary of the flow path. As another example, a flow path assembly comprises a combustor dome positioned a forward end of a combustor; an outer wall extending from the combustor dome through at least a first turbine stage; and an inner wall extending from the combustor dome through at least a combustion section. The combustor dome extends radially from the outer wall to the inner wall and is integrally formed with the outer and inner walls as a single unitary structure.

Abstract: Flow path assemblies and methods for forming such flow path assemblies for gas turbine engines are provided. For example, a flow path assembly for a gas turbine engine has a boundary structure, an airfoil, and a locking feature. The boundary structure and the airfoil are formed from a composite material. The boundary structure defines an opening and a cutout proximate the opening, and the airfoil is sized to fit within the opening of the boundary structure. The locking feature is received within the cutout defined by the boundary structure to interlock the airfoil with the boundary structure.

Abstract: Combustor dome assemblies having combustor deflectors are provided. For example, a combustor dome assembly comprises a combustor dome defining an opening; a ceramic matrix composite (CMC) deflector positioned adjacent the combustor dome on an aft side of the assembly; a fuel-air mixer defining a groove about an outer perimeter thereof; and a seal plate including a key. The CMC deflector includes a cup extending forward through the opening in the combustor dome that defines one or more bayonets and a slot. The bayonets are received in the fuel-air mixer groove, and the seal plate key is received in the CMC deflector slot. In another embodiment, where the seal plate may be omitted, a spring is positioned between the fuel-air mixer and the CMC deflector to hold the CMC deflector in place with respect to the combustor dome. Methods of assembling combustor dome assemblies having CMC deflectors also are provided.

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: Combustor dome assemblies having combustor deflectors are provided. For example, a combustor dome assembly comprises a combustor dome defining an opening; a ceramic matrix composite (CMC) deflector positioned adjacent the combustor dome on an aft side of the assembly; a fuel-air mixer defining a groove about an outer perimeter thereof; and a seal plate including a key. The CMC deflector includes a cup extending forward through the opening in the combustor dome that defines one or more bayonets and a slot. The bayonets are received in the fuel-air mixer groove, and the seal plate key is received in the CMC deflector slot. In another embodiment, where the seal plate may be omitted, a spring is positioned between the fuel-air mixer and the CMC deflector to hold the CMC deflector in place with respect to the combustor dome. Methods of assembling combustor dome assemblies having CMC deflectors also are provided.

Abstract: Gas turbine engines, as well as outer walls and flow path assemblies of gas turbine engines, are provided. For example, an outer wall of a flow path comprises a combustor portion extending through a combustion section, and a turbine portion extending through at least a first turbine stage of a turbine section. The combustor and turbine portions are integrally formed as a single unitary structure that defines an outer boundary of the flow path. As another example, a flow path assembly comprises a combustor dome positioned a forward end of a combustor; an outer wall extending from the combustor dome through at least a first turbine stage; and an inner wall extending from the combustor dome through at least a combustion section. The combustor dome extends radially from the outer wall to the inner wall and is integrally formed with the outer and inner walls as a single unitary structure.

Abstract: A flow path assembly for a gas turbine engine is provided. The flow path assembly may include an outer casing comprising a metal material having a first coefficient of thermal expansion, a ceramic structure comprising a ceramic material having a second coefficient of thermal expansion, and a mounting component attached on a first end to the outer casing and attached on a second end to the ceramic structure. The mounting component may be constructed from at least two materials transitioning from the first end to the second end such that the coefficient of thermal expansion is different at the first end than the second end.

Abstract: Flow path assemblies for gas turbine engines are provided. For example, a flow path assembly defining a flow path through a gas turbine engine, as well as axial and radial directions that are orthogonal to one another and a circumferential direction extending about the axial direction, comprises a nozzle airfoil having a first end opposite a second end and a wall defining a flow path boundary. The wall has an opening therein through which the second end of the nozzle airfoil protrudes such that the second end extends outside of the flow path. The flow path assembly further comprises a cap extending over the second end of the nozzle airfoil and an attachment member extending through the second end and the cap to attach the second end to the cap. Other embodiments of a flow path assembly having nozzle airfoils decoupled from the flow path boundary also are provided.

Abstract: Gas turbine engines, as well as outer walls and flow path assemblies of gas turbine engines, are provided. For example, an outer wall of a flow path comprises a combustor portion extending through a combustion section, and a turbine portion extending through at least a first turbine stage of a turbine section. The combustor and turbine portions are integrally formed as a single unitary structure that defines an outer boundary of the flow path. As another example, a flow path assembly comprises a combustor dome positioned a forward end of a combustor; an outer wall extending from the combustor dome through at least a first turbine stage; and an inner wall extending from the combustor dome through at least a combustion section. The combustor dome extends radially from the outer wall to the inner wall and is integrally formed with the outer and inner walls as a single unitary structure.

Abstract: Methods for assembling flow path structures having one or more unitary components are provided. For example, one method for assembling a flow path assembly of a gas turbine engine comprises stacking axially adjacent components within a generally annular outer wall of the flow path assembly. The flow path assembly defines a flow path through a combustion section and at least a portion of a turbine section of the gas turbine engine. The outer wall defines an outer boundary of the flow path, and the axially adjacent components defining at least a portion of an inner boundary of the flow path. The outer wall is a unitary outer wall that includes a combustor portion extending through the combustion section and a turbine portion extending through at least a first turbine stage of the turbine section. The combustor and turbine portions are integrally formed as a single unitary structure.

Abstract: Flow path assemblies having features for positioning the assemblies within a gas turbine engine are provided. For example, a flow path assembly comprises an inner wall and a unitary outer wall that includes an integral combustion portion and turbine portion, the combustor portion extending through a combustion section of the gas turbine engine and the turbine portion extending through at least a first turbine stage of a turbine section of the gas turbine engine. The flow path assembly further comprises at least two positioning members for radially centering the flow path assembly within the gas turbine engine. The positioning members extend to the flow path assembly from one or more structures external to the flow path assembly, constrain the flow path assembly tangentially, and allow radial and axial movement of the flow path assembly. Other embodiments for positioning flow path assemblies also are provided.

Abstract: A flow path assembly for a gas turbine engine is provided. The flow path assembly may include an outer casing comprising a metal material having a first coefficient of thermal expansion, a ceramic structure comprising a ceramic material having a second coefficient of thermal expansion, and a mounting component attached on a first end to the outer casing and attached on a second end to the ceramic structure. The mounting component may be constructed from at least two materials transitioning from the first end to the second end such that the coefficient of thermal expansion is different at the first end than the second end.

Abstract: Flow path assemblies having features for positioning the assemblies within a gas turbine engine are provided. For example, a flow path assembly comprises an inner wall and a unitary outer wall that includes an integral combustion portion and turbine portion, the combustor portion extending through a combustion section of the gas turbine engine and the turbine portion extending through at least a first turbine stage of a turbine section of the gas turbine engine. The flow path assembly further comprises at least two positioning members for radially centering the flow path assembly within the gas turbine engine. The positioning members extend to the flow path assembly from one or more structures external to the flow path assembly, constrain the flow path assembly tangentially, and allow radial and axial movement of the flow path assembly. Other embodiments for positioning flow path assemblies also are provided.

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.