Abstract: A gas turbine engine assembly includes a static component and a rotatable component configured to rotate about a central axis of the gas turbine engine assembly relative to the static component. The gas turbine engine assembly further includes a vibration-dampening system configured to dampen vibration of the gas turbine engine assembly.

Abstract: A blisk assembly for vibration dampening includes a disk portion extending circumferentially about a central axis of the blisk, a plurality of blades integrally coupled to the disk, and a piezoelectric damping ring that includes a damping ring and a plurality of piezoelectric elements coupled to the damping ring. The disk portion includes a groove configured to receive the piezoelectric damping ring. As a result of centrifugal forces applied to the piezoelectric damping ring during rotation of the blisk assembly, mechanical energy may be generated at one or more of the plurality of piezoelectric elements, which is converted to electrical energy and transmitted to another one or more of the plurality of piezoelectric elements. Accordingly, the one or more of the piezoelectric elements having received the electricity can convert the electricity to mechanical energy to provide vibration damping.

Abstract: A blisk assembly for vibration dampening includes a disk portion extending circumferentially about a central axis of the blisk, a plurality of blades integrally coupled to the disk, and a piezoelectric damping ring that includes a damping ring and a plurality of piezoelectric elements coupled to the damping ring. The disk portion includes a groove configured to receive the piezoelectric damping ring. As a result of centrifugal forces applied to the piezoelectric damping ring during rotation of the blisk assembly, mechanical energy may be generated at one or more of the plurality of piezoelectric elements, which is converted to electrical energy and transmitted to another one or more of the plurality of piezoelectric elements. Accordingly, the one or more of the piezoelectric elements having received the electricity can convert the electricity to mechanical energy to provide vibration damping.

Abstract: A gas turbine engine airflow member is disclosed having spherical interface shapes at a tip end and a hub end. In one embodiment, the airflow member is a fan blade. The spherical interface shapes can be convex or concave. In one form, the tip end spherical shape is axially shifted aft relative to a hub end. The tip end can include relatively little forward portion in an expanding flow path with predominant portion of the tip end in a contracting flow path. Such a configuration can occur with a midpoint and trailing edge located in the contracting flow path. A center of gravity of a swept airflow member having spherical end shape can be located on a pivot axis of the airflow member. Divot depressions can be provided to permit concave flow path shapes.

Abstract: A nacelle for a gas turbine jet engine for an aircraft includes plasma actuators that act as flow disruptors to provide boundary layer turbulence when the engine is exposed to air flow that is obtuse or perpendicular to direction of travel of the engine.

Abstract: A fan for a gas turbine engine is disclosed. The fan includes a fan disk and a plurality of fan blades coupled to the fan disk. The fan disk is adapted for rotation about a central axis. The fan blades are coupled to the fan disk for rotation therewith about the central axis.

Abstract: A fan assembly for use in a gas turbine engine includes a fan wheel and a plurality of blades extending radially from the fan wheel away from a central axis of the fan assembly. Each of the blades includes a root coupled with the fan wheel and an airfoil extending radially outwardly from the root. The blades are adapted to rotate about the central axis to push air.

Abstract: A nacelle for a gas turbine jet engine for an aircraft includes flow disruptors to provide boundary layer turbulence when the engine is exposed to air flow that is obtuse to direction of travel of the engine.

Abstract: A gas turbine engine assembly includes a static component and a rotatable component configured to rotate about a central axis of the gas turbine engine assembly relative to the static component. The gas turbine engine assembly further includes a vibration-dampening system configured to dampen vibration of the gas turbine engine assembly.

Abstract: A rotor for a gas turbine engine includes a central wheel and a plurality of blades that extend outwardly from the central wheel. The blades are non-uniform to reduce flutter and forced response effects induced during operation of a gas turbine engine including the rotor.

Abstract: A gas turbine engine airflow member is disclosed having spherical interface shapes at a tip end and a hub end. In one embodiment, the airflow member is a fan blade. The spherical interface shapes can be convex or concave. In one form, the tip end spherical shape is axially shifted aft relative to a hub end. The tip end can include relatively little forward portion in an expanding flow path with predominant portion of the tip end in a contracting flow path. Such a configuration can occur with a midpoint and trailing edge located in the contracting flow path. A center of gravity of a swept airflow member having spherical end shape can be located on a pivot axis of the airflow member. Divot depressions can be provided to permit concave flow path shapes.

Abstract: A blisk assembly for vibration dampening includes a disk portion extending circumferentially about a central axis of the blisk, a plurality of blades integrally coupled to the disk, and a piezoelectric damping ring that includes a damping ring and a plurality of piezoelectric elements coupled to the damping ring. The disk portion includes a groove configured to receive the piezoelectric damping ring. As a result of centrifugal forces applied to the piezoelectric damping ring during rotation of the blisk assembly, mechanical energy may be generated at one or more of the plurality of piezoelectric elements, which is converted to electrical energy and transmitted to another one or more of the plurality of piezoelectric elements. Accordingly, the one or more of the piezoelectric elements having received the electricity can convert the electricity to mechanical energy to provide vibration damping.

Abstract: An integrated access panel is disclosed that can be used to assist in adjusting a component like a fan blade of a turbofan engine. in one form the integrated access panel is hinged at one end such that the panel remains attached during adjustment of the fan blade. The access panel can be positioned in an angled flow surface of a nacelle such that the fan blade cannot be removed from a wheel without removal of the nacelle or opening of the access panel. The integrated access panel can be spring-loaded and positioned to allow the fan blade to be removed from a wheel by moving the access panel out of the way. Subsequent blade removal can occur by rotation of the wheel to locate another blade in proximity to the access panel.

Abstract: A gas turbine engine airflow member is disclosed having spherical interface shapes at a tip end and a hub end. In one embodiment, the airflow member is a fan blade. The spherical interface shapes can be convex or concave. In one form, the tip end spherical shape is axially shifted aft relative to a hub end. The tip end can include relatively little forward portion in an expanding flow path with predominant portion of the tip end in a contracting flow path. Such a configuration can occur with a midpoint and trailing edge located in the contracting flow path. A center of gravity of a swept airflow member having spherical end shape can be located on a pivot axis of the airflow member. Divot depressions can be provided to permit concave flow path shapes.

Abstract: A flow path surface of a gas turbine engine at the location of a bladed component is disclosed in which the flow path surface includes a cylindrical upstream side and a conical downstream side. The bladed component is located at the intersection of the cylindrical upstream side and the conical downstream side. The cylindrical upstream side can extend from a leading edge of the bladed component, or a point upstream of it, to a location between the leading edge and trailing edge of the component. The conical downstream side can extend past the trailing edge of the bladed component. The bladed component can be a fan blade or a compressor blade.

Abstract: A nacelle for a gas turbine jet engine for an aircraft includes plasma actuators that act as flow disruptors to provide boundary layer turbulence when the engine is exposed to air flow that is obtuse or perpendicular to direction of travel of the engine.

Abstract: A fan for a gas turbine engine is disclosed. The fan includes a fan disk and a plurality of fan blades coupled to the fan disk. The fan disk is adapted for rotation about a central axis. The fan blades are coupled to the fan disk for rotation therewith about the central axis.

Abstract: A fan assembly for use in a gas turbine engine includes a fan wheel and a plurality of blades extending radially from the fan wheel away from a central axis of the fan assembly. Each of the blades includes a root coupled with the fan wheel and an airfoil extending radially outwardly from the root. The blades are adapted to rotate about the central axis to push air.

Abstract: A blisk assembly for vibration dampening includes a disk portion extending circumferentially about a central axis of the blisk, a plurality of blades integrally coupled to the disk, and a piezoelectric damping ring that includes a damping ring and a plurality of piezoelectric elements coupled to the damping ring. The disk portion includes a groove configured to receive the piezoelectric damping ring. As a result of centrifugal forces applied to the piezoelectric damping ring during rotation of the blisk assembly, mechanical energy may be generated at one or more of the plurality of piezoelectric elements, which is converted to electrical energy and transmitted to another one or more of the plurality of piezoelectric elements. Accordingly, the one or more of the piezoelectric elements having received the electricity can convert the electricity to mechanical energy to provide vibration damping.

Abstract: A nacelle for a gas turbine jet engine for an aircraft includes flow disruptors to provide boundary layer turbulence when the engine is exposed to air flow that is obtuse to direction of travel of the engine.