Abstract: A gas turbine engine includes a fan section including a fan. A fan nacelle surrounds the fan and includes an inlet with an inlet leading edge plane and a throat. A compressor section is arranged in a core nacelle and includes a first compressor and a second compressor. A turbine section is arranged in the core nacelle and includes a fan drive turbine and a second turbine. A fan hub mounts the fan and a spinner axially forward of the fan. The fan drive turbine drives the fan through a geared architecture. The fan includes a fan leading edge forward-most point spaced apart from the inlet leading edge plane by an inlet length. The spinner includes a spinner length from a spinner forward-most point to the fan leading edge forward-most point. A ratio of the spinner length to inlet length is greater than or equal to 0.5.

Abstract: A gas turbine engine that includes a fan nacelle and a core nacelle that provide a bypass flow path radially between. The fan nacelle has an inlet including a throat. The inlet has an inlet forward-most point. A fan is arranged in the bypass flow path and rotatable about an axis. The fan has a leading edge recessed from the inlet forward-most point an inlet length in an axial direction. A spinner has a spinner length from a spinner forward-most point to the leading edge. A ratio of the spinner length to inlet length is equal to or greater than about 0.5.

Abstract: A compressor with negative coefficient of thermal expansion case material comprising a rotor having blades with tips, the case including an inner case comprising a negative coefficient of thermal expansion material, and a tip clearance located between the tips and the inner case; wherein the tip clearance is maintained responsive to a flow of air over the negative coefficient of thermal expansion material.

Abstract: A compressor with negative coefficient of thermal expansion case material comprising a rotor having blades with tips, the case including an inner case comprising a negative coefficient of thermal expansion material, and a tip clearance located between the tips and the inner case; wherein the tip clearance is maintained responsive to a flow of air over the negative coefficient of thermal expansion material.

Abstract: A gas turbine engine includes a compressor section, a combustor section downstream from the compressor section, and a turbine section downstream from the combustor section. The gas turbine engine also includes a water tank with an outlet, and an injector fluidically connected to the outlet of the water tank and to the turbine section. The injector is configured to direct steam from the water tank into the turbine section.

Abstract: A gas turbine engine that includes a fan nacelle and a core nacelle that provide a bypass flow path radially between. The fan nacelle has an inlet including a throat. The inlet has an inlet forward-most point. A fan is arranged in the bypass flow path and rotatable about an axis. The fan has a leading edge recessed from the inlet forward-most point an inlet length in an axial direction. A spinner has a spinner length from a spinner forward-most point to the leading edge. A ratio of the spinner length to inlet length is equal to or greater than about 0.5.

Abstract: A propulsion system includes an engine with a fan and a nacelle that circumscribes the engine. The engine defines an axis. A distance between a forwardmost point at the top of the nacelle and at the front of the nacelle to a forwardmost point of the fan is greater than a distance between a forwardmost point at the bottom of the nacelle and at the front of the nacelle.

Abstract: A propulsion system includes an engine with a fan and a nacelle that circumscribes the engine. The engine defines an axis. A distance between a forwardmost point at the top of the nacelle and at the front of the nacelle to a forwardmost point of the fan is greater than a distance between a forwardmost point at the bottom of the nacelle and at the front of the nacelle.

Abstract: An inlet of a nacelle for channeling inlet airflow to a fan of a gas turbine engine includes a forward lip and an inner surface. The forward lip extends around a centerline axis of the engine and is adapted to accommodate a flow angle of incoming airflow. The inner surface extends from the forward lip along the centerline axis of the engine to adjacent the fan. The inner surface has a first profile above the centerline axis of the engine and a second profile below the centerline axis of the engine. The first profile and the second profile are adapted to define an inlet centerline axis that extends below the centerline axis of the engine at a face of the fan.

Abstract: An inlet of a nacelle for channeling inlet airflow to a fan of a gas turbine engine includes a forward lip and an inner surface. The forward lip extends around a centerline axis of the engine and is adapted to accommodate a flow angle of incoming airflow. The inner surface extends from the forward lip along the centerline axis of the engine to adjacent the fan. The inner surface has a first profile above the centerline axis of the engine and a second profile below the centerline axis of the engine. The first profile and the second profile are adapted to define an inlet centerline axis that extends below the centerline axis of the engine at a face of the fan.

Abstract: A turbo machine includes a housing having a bearing compartment for receiving lubrication. The housing also provides a buffer compartment for receiving air, for example, compressor bleed air. A turbine shaft is supported within the housing on a bearing for rotation relative to the housing. The bearing is arranged within the bearing compartment. A seal is arranged between the turbine shaft and the housing and separates the bearing and buffer compartments. The seal includes opposing lubrication and air sides that are respectively exposed to the bearing and buffer compartments. The buffer tube is fluidly connected to a body of the buffer compartment. A buffer tube introduces flow generally tangential to an inner surface of the body for generating a swirl within the body. The buffer tube includes a velocity control device such a venturi arranged at an exit of the tube to control the velocity of the flow entering the body.

Abstract: A turbo machine includes a housing having a bearing compartment for receiving lubrication. The housing also provides a buffer compartment for receiving air, for example, compressor bleed air. A turbine shaft is supported within the housing on a bearing for rotation relative to the housing. The bearing is arranged within the bearing compartment. A seal is arranged between the turbine shaft and the housing and separates the bearing and buffer compartments. The seal includes opposing lubrication and air sides that are respectively exposed to the bearing and buffer compartments. The buffer tube is fluidly connected to a body of the buffer compartment. A buffer tube introduces flow generally tangential to an inner surface of the body for generating a swirl within the body. The buffer tube includes a velocity control device such a venturi arranged at an exit of the tube to control the velocity of the flow entering the body.

Abstract: A discharge collector and diffuser for a screw compressor, including a housing having an inlet for receiving flow from a compressor and an outlet and defining therebetween a collector portion, a transition portion and a diffuser portion, the collector portion being adapted to receive a plurality of non-parallel streams from a compressor and to guide the streams into a substantially parallel flow direction, the housing further having a splitter plate positioned in the collector portion to separate the non-parallel streams from each other, whereby the streams are maintained separate until they are substantially parallel, thereby reducing flow losses.

Abstract: An acoustic resonator for use in an engine is provided. The acoustic resonator includes a cavity having a volume, an aperture, and a passage connecting the aperture and the cavity. The aperture has a profiled surface for delaying separation of fluid entering the passage and for reducing losses caused by fluid separation.