Abstract:
A shroud hanger assembly or shroud assembly is provided for a gas turbine engine wherein a hanger includes a radially depending and axially extending arm. The arm or retainer engages a pocket formed in a shroud so as to retain the shroud in a desired position relative to the hanger. An aft retaining structure is provided on the hanger and provides a seat for a seal structure which biases the retainer so that the arm of the hanger maintains engagement in the shroud pocket. A baffle may be utilized at the hanger to cool at least some portion of the shroud.
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:
A rotor assembly apparatus that includes a rotatable component and a ring-shroud. The rotatable component is mounted for rotation about a first axis. The ring-shroud defines an inner surface that surrounds the rotatable component and that defines a second axis. A sensing system is configured to monitor the position of the first axis relative to the second axis. A casing surrounds the ring-shroud and an actuation system is configured to move the ring-shroud relative to the casing, in response to the sensing system.
Abstract:
A shroud hanger assembly or shroud assembly is provided for components which may be formed of materials having differing coefficient thermal expansion. The assembly includes a multi-piece hanger including a shroud positioned in a cavity between a first hanger portion and a second hanger portion. A shroud may be formed of a low coefficient of thermal expansion material which may have a differing coefficient thermal expansion than the material defining the shroud hanger. The shroud is deflected by an axial force acting between the hanger and the shroud which also forms a seal. The seal compensates for differing rates of thermal growth between the shroud and the hanger throughout the engine operating envelope.
Abstract:
Flow path assemblies for gas turbine engines are provided. For example, a flow path assembly comprises an inner wall; a unitary outer wall; and a plurality of nozzle airfoils having an inner end radially opposite an outer end. The unitary outer wall defines a plurality of outer pockets each configured for receipt of the outer end of one of the nozzle airfoils, and the inner wall includes defines a plurality of inner pockets each configured for receipt of the inner end of one of the plurality of nozzle airfoils. A portion of each inner pocket is defined by a forward inner wall segment and an aft inner wall segment. In another embodiment, a flow path assembly comprises an inner wall defining a plurality of bayonet slots that each receive a bayonet included with each of a plurality of nozzle airfoils that are integral with a unitary outer wall.
Abstract:
In one aspect the present subject matter is directed to a system for thermally shielding a portion of a shroud assembly for a gas turbine. The system includes a shroud support having a forward wall that includes a front side that is axially spaced from a back side and a radially inner surface that extends axially between the front and back sides. A shroud is mounted to the shroud support. The shroud includes a leading edge portion that extends towards the forward wall of the shroud support and a trailing edge portion that extends towards the aft wall of the shroud support. A radial gap is defined between a top surface of the leading edge portion and the radially inner surface of the forward wall. A thermal shield is disposed along a bottom portion of the forward wall and is oriented to face towards a flow of combustion gases.
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:
In one aspect the present subject matter is directed to a system for supporting a turbine shroud. The system includes a shroud support at least partially defining a first piston sleeve and a piston assembly having a first piston head disposed within the first piston sleeve and a second piston head coupled to the first piston head. The first piston head is slideably engaged with an inner surface of the first piston sleeve. The second piston head is slideably engaged with an inner surface of a second piston sleeve. The system also includes a turbine shroud that is fixedly connected to the piston assembly and that extends radially inwardly from the shroud support. The piston assembly provides for radially inward and radially outward movement of the turbine shroud in response to a change in a radial force applied to a hot side surface of the turbine shroud.
Abstract:
In one aspect the present subject matter is directed to a system for thermally shielding a portion of a shroud assembly for a gas turbine. The system includes a shroud support having a forward wall that includes a front side that is axially spaced from a back side and a radially inner surface that extends axially between the front and back sides. A shroud is mounted to the shroud support. The shroud includes a leading edge portion that extends towards the forward wall of the shroud support and a trailing edge portion that extends towards the aft wall of the shroud support. A radial gap is defined between a top surface of the leading edge portion and the radially inner surface of the forward wall. A thermal shield is disposed along a bottom portion of the forward wall and is oriented to face towards a flow of combustion gases.
Abstract:
Ceramic matrix composite articles include, for example a first plurality of plies of ceramic fibers in a ceramic matrix defining a first extent, and a local at least one second ply in said ceramic matrix defining a second extent on and/or in said first plurality of plies with the second extent being less than said first extent. The first plurality of plies has a first property, the at least one second ply has at least one second property, and said first property being different from said at least one second property. The different properties may include one or more different mechanical (stress/strain) properties, one or more different thermal conductivity properties, one or more different electrical conductivity properties, one or more different other properties, and combinations thereof.