Abstract: A gas turbine and nozzle system is provided that includes a radial inflow turbine rotor and a volute providing a flow path to deliver a pressurized gas to a circumference of the radial turbine rotor. The volute incorporates a shape which substantially conforms to a radial turbine shroud contour. The volute includes at least first and second parts. A mating surface between the first and second parts is substantially aligned with a direction of pressurized gas flow in the volute.

Abstract: A gas turbine and nozzle system is provided that includes a radial inflow turbine rotor and a volute providing a flow path to deliver a pressurized gas to a circumference of the radial turbine rotor. The volute incorporates a shape which substantially conforms to a radial turbine shroud contour. The volute includes at least first and second parts. A mating surface between the first and second parts is substantially aligned with a direction of pressurized gas flow in the volute.

Abstract: A means of attachment applicable to mating parts which have substantially different coefficients of thermal expansion is disclosed. The means of attachment substantially reduces the friction between the mating surfaces while still keeping the mating parts centered with respect to one another. The approach is based on radial recessed faces wherein the radial faces slide relative to each other. There may be three or more recessed/raised faces on each mating component, which when mated, maintain the alignment between the mating parts while allowing differential growth of the mating parts. This approach also the provides a much larger bearing surface for the attachment than a radial pin/slot approach, for example, and substantially eliminates areas of high stress concentration. It is thus a more robust design for components that undergo many thousands of thermal cycles.

Abstract: A gas turbine and nozzle system is provided that includes a radial inflow turbine rotor and a volute providing a flow path to deliver a pressurized gas to a circumference of the radial turbine rotor. The volute incorporates a shape which substantially conforms to a radial turbine shroud contour. The volute includes at least first and second parts. A mating surface between the first and second parts is substantially aligned with a direction of pressurized gas flow in the volute.

Abstract: A method and apparatus are disclosed for a gas turbine spool design combining metallic and ceramic components in a way that controls clearances between critical components over a range of engine operating temperatures and pressures. In a first embodiment, a ceramic turbine rotor rotates just inside a ceramic shroud and separated by a small clearance gap. The ceramic rotor is connected to a metallic volute. In order to accommodate the differential rates of thermal expansion between the ceramic rotor and metallic volute, an active clearance control system is used to maintain the desired axial clearance between ceramic rotor and the ceramic shroud over the range of engine operating temperatures. In a second embodiment, a ceramic turbine rotor rotates just inside a ceramic shroud which is part of a single piece ceramic volute/shroud assembly.

Abstract: A means of attachment applicable to mating parts which have substantially different coefficients of thermal expansion is disclosed. The means of attachment substantially reduces the friction between the mating surfaces while still keeping the mating parts centered with respect to one another. The approach is based on radial recessed faces wherein the radial faces slide relative to each other. There may be three or more recessed/raised faces on each mating component, which when mated, maintain the alignment between the mating parts while allowing differential growth of the mating parts. This approach also the provides a much larger bearing surface for the attachment than a radial pin/slot approach, for example, and substantially eliminates areas of high stress concentration. It is thus a more robust design for components that undergo many thousands of thermal cycles.

Abstract: A method and apparatus are disclosed for a gas turbine spool design combining metallic and ceramic components in a way that controls clearances between critical components over a range of engine operating temperatures and pressures. In a first embodiment, a ceramic turbine rotor rotates just inside a ceramic shroud and separated by a small clearance gap. The ceramic rotor is connected to a metallic volute. In order to accommodate the differential rates of thermal expansion between the ceramic rotor and metallic volute, an active clearance control system is used to maintain the desired axial clearance between ceramic rotor and the ceramic shroud over the range of engine operating temperatures. In a second embodiment, a ceramic turbine rotor rotates just inside a ceramic shroud which is part of a single piece ceramic volute/shroud assembly.