Abstract: A bleed valve assembly includes a manifold coupled to a case of a compressor of a gas turbine engine to control a flow of bleed air exiting the compressor, a valve housing coupled with the manifold, a piston configured to move selectively relative to the valve housing and the manifold, and one or more shims located between the valve housing and the piston.

Abstract: A gas turbine engine includes a compressor, a combustor, and a turbine. The compressor compresses gases entering the gas turbine engine. The combustor receives the compressed gases from the compressor and mixes fuel with the compressed gases. The turbine receives the hot, high pressure combustion products created by the combustor by igniting the fuel mixed with the compressed gases. The turbine extracts mechanical work from the hot, high pressure combustion products to drive the compressor and a fan, shaft, or propeller.

Abstract: A gas turbine engine includes a compressor, a combustor, and a turbine. The compressor compresses gases entering the gas turbine engine. The combustor receives the compressed gases from the compressor and mixes fuel with the compressed gases. The turbine receives the hot, high pressure combustion products created by the combustor by igniting the fuel mixed with the compressed gases. The turbine extracts mechanical work from the hot, high pressure combustion products to drive the compressor and a fan, shaft, or propeller.

Abstract: A gas turbine engine includes a fan, a compressor, a combustor, and a turbine. The compressor compresses gases entering the gas turbine engine. The combustor receives the compressed gases from the compressor and mixes fuel with the compressed gases. The turbine receives the hot, high pressure combustion products created by the combustor by igniting the fuel mixed with the compressed gases. The turbine extracts mechanical work from the hot, high pressure combustion products to drive the fan and compressor.

Abstract: A gas turbine engine includes a compressor, a combustor, and a turbine. The compressor compresses gases entering the gas turbine engine. The combustor receives the compressed gases from the compressor and mixes fuel with the compressed gases. The turbine receives the hot, high pressure combustion products created by the combustor by igniting the fuel mixed with the compressed gases. The turbine extracts mechanical work from the hot, high pressure combustion products to drive the compressor and a fan, shaft, or propeller.

Abstract: A gas turbine engine includes a fan, a compressor, a combustor, and a turbine. The compressor compresses gases entering the gas turbine engine. The combustor receives the compressed gases from the compressor and mixes fuel with the compressed gases. The turbine receives the hot, high pressure combustion products created by the combustor by igniting the fuel mixed with the compressed gases. The turbine extracts mechanical work from the hot, high pressure combustion products to drive the fan and compressor.

Abstract: A gas turbine engine includes a fan, a compressor, a combustor, and a turbine. The compressor compresses gases entering the gas turbine engine. The combustor receives the compressed gases from the compressor and mixes fuel with the compressed gases. The turbine receives the hot, high pressure combustion products created by the combustor by igniting the fuel mixed with the compressed gases. The turbine extracts mechanical work from the hot, high pressure combustion products to drive the fan and compressor.

Abstract: A gas turbine engine includes a fan, a compressor, a combustor, and a turbine. The compressor compresses gases entering the gas turbine engine. The combustor receives the compressed gases from the compressor and mixes fuel with the compressed gases. The turbine receives the hot, high pressure combustion products created by the combustor by igniting the fuel mixed with the compressed gases. The turbine extracts mechanical work from the hot, high pressure combustion products to drive the fan and compressor.

Abstract: A compressor includes an impeller and a diffuser. The impeller is mounted for rotation about an axis of the gas turbine engine. The diffuser is coupled to the impeller to receive the high velocity air from the impeller. The diffuser includes a first plate, a second plate spaced apart from the first plate axially, and a plurality of vanes located between the first and second plates.

Abstract: A compressor includes an impeller and a diffuser. The impeller is mounted for rotation about an axis of the gas turbine engine. The diffuser is coupled to the impeller to receive the high velocity air from the impeller. The diffuser includes a first plate, a second plate spaced apart from the first plate axially, and a plurality of vanes located between the first and second plates.

Abstract: A gas turbine engine includes a fan, a compressor, a combustor, and a turbine. The compressor compresses gases entering the gas turbine engine. The combustor receives the compressed gases from the compressor and mixes fuel with the compressed gases. The turbine receives the hot, high pressure combustion products created by the combustor by igniting the fuel mixed with the compressed gases. The turbine extracts mechanical work from the hot, high pressure combustion products to drive the fan and compressor.

Abstract: A diffuser assembly is disclosed for conditioning the effluent of a centrifugal compressor. The diffuser assembly comprises an annular conduit, a first set of vanes, and a second set of vanes. The annular conduit comprises a first wall and a second wall displaced from each other and cooperating to define an inlet, an outlet, and a passage extending from the inlet to the outlet. The passage has a first linear portion, a curved portion, and a second linear portion. The first set of vanes are positioned in the first linear portion of said passage. The second set of vanes are positioned in the curved portion of the passage. Each vane of the second set of vanes curves axially and laterally from a vane leading edge to a vane trailing edge.

Abstract: A centrifugal impeller is disclosed having a non-axisymmetric flowpath surface. The centrifugal compressor may comprise a hub and a plurality of circumferentially spaced vanes. The hub has a flowpath surface and an axis of rotation. The plurality of circumferentially spaced vanes extend from the flowpath surface, with each of the vanes having a pressure-side fillet and a suction-side fillet extending from a leading edge to a trailing edge of the vane. The pressure-side fillet and suction-side fillet intersect the flowpath surface at a runout. The runout of the pressure-side fillet of a first vane is asymmetric to the runout of the suction-side fillet of the first vane.

Abstract: A diffuser assembly is disclosed for conditioning the effluent of a centrifugal compressor. The diffuser assembly comprises an annular conduit, a first set of vanes, and a second set of vanes. The annular conduit comprises a first wall and a second wall displaced from each other and cooperating to define an inlet, an outlet, and a passage extending from the inlet to the outlet. The passage has a first linear portion, a curved portion, and a second linear portion. The first set of vanes are positioned in the first linear portion of said passage. The second set of vanes are positioned in the curved portion of the passage. Each vane of the second set of vanes curves axially and laterally from a vane leading edge to a vane trailing edge.

Abstract: A centrifugal impeller is disclosed having a non-axisymmetric flowpath surface. The centrifugal compressor may comprise a hub and a plurality of circumferentially spaced vanes. The hub has a flowpath surface and an axis of rotation. The plurality of circumferentially spaced vanes extend from the flowpath surface, with each of the vanes having a pressure-side fillet and a suction-side fillet extending from a leading edge to a trailing edge of the vane. The pressure-side fillet and suction-side fillet intersect the flowpath surface at a runout. The runout of the pressure-side fillet of a first vane is asymmetric to the runout of the suction-side fillet of the first vane.

Abstract: An engine includes a compressor having a first compressor, a second compressor, and a static hub transition duct. The first compressor includes a rotatable portion and a static portion. The second compressor is disposed downstream of the first compressor and includes an inlet and a rotatable portion. The static hub transition duct includes an inner wall and an outer wall. The inner wall is secured to the static portion of the first compressor, and the inner wall and outer wall define a space that fluidically couples the first compressor and the inlet of the second compressor.

Abstract: A method of random access communication uses subbanding and variable length messages to provide efficient communication between a plurality of mobile earth terminals and a plurality of satellites. The subbanding allows each satellite to more efficiently process communications from mobile earth terminals operating under a variety of different rules or regulations. The satellite receivers can be dynamically reconfigured such that they can receive messages of different lengths at different times. The mobile earth terminals can change the size of the messages that they send to take advantage of the newly reconfigured satellite receiver(s). The method can reduce or eliminate errors or delays that occur in prior methods of random access communication.

Abstract: A method of random access communication uses subbanding and variable length messages to provide efficient communication between a plurality of mobile earth terminals and a plurality of satellites. The subbanding allows each satellite to more efficiently process communications from mobile earth terminals operating under a variety of different rules or regulations. The satellite receivers can be dynamically reconfigured such that they can receive messages of different lengths at different times. The mobile earth terminals can change the size of the messages that they send to take advantage of the newly reconfigured satellite receiver(s). The method can reduce or eliminate errors or delays that occur in prior methods of random access communication.