Abstract: A variable-geometry convergent-divergent exhaust nozzle includes: a duct to receive exhaust from a combustor; and first and second flap assemblies each including proximal and distal flaps. The first and second proximal flaps are rotatably coupled to the exhaust duct and include entry surfaces that in part define a nozzle passageway to convey the exhaust to an exterior of the engine. The first and second distal flaps are rotatably coupled to the first and second proximal flaps. The first distal flap includes converging and diverging surfaces angled with respect to each other. The second distal flap includes converging and diverging surfaces angled with respect to each other. The converging surfaces define at least in part a convergent portion of the nozzle passageway. The first and second diverging surfaces define at least in part a divergent portion of the nozzle passageway.

Abstract: An exhaust nozzle for a gas turbine engine includes: an exhaust duct configured to receive an exhaust flow of gas from a combustor of the engine; a first flap rotatably coupled to the exhaust duct for rotation about a first axis; a first actuator configured to actuate the first flap about the first axis between a first inner and a first outer position; a second flap rotatably coupled to the exhaust duct for rotation about a second axis; and a second actuator configured to actuate the second flap about the second axis between a second inner and a second outer position. The first and second flaps at least in part define a passageway configured to convey the exhaust flow of gas to an exterior of the gas turbine engine. The first and second axes of rotation are coaxial. Also provides is a method of operating an exhaust nozzle.

Abstract: Disclosed is an exhaust nozzle for a gas turbine engine, the exhaust nozzle comprising an outer frame extending along a longitudinal direction, a convergent petal pivotably attached to the frame and extending axially downstream and radially inward from the pivot, radially within the frame, and a sealing hinge arrangement between an upstream member and a downstream member of the exhaust nozzle. One of the upstream member or the downstream member defines a cylindrical socket having an opening along a cylinder axis which receives a corresponding cylindrical hinge element the other of the downstream member or upstream member, where the upstream member is defined by the frame and the downstream member is the convergent petal; or the exhaust nozzle further comprises a divergent petal downstream of the convergent petal and pivotably attached to the convergent petal, the upstream member being the convergent petal and the downstream member being the divergent petal.

Abstract: There is disclosed an exhaust nozzle for a gas turbine engine, the exhaust nozzle comprising a frame extending along a longitudinal axis. The exhaust nozzle comprises a convergent petal pivotably attached at a convergent pivot point to the frame and extending axially downstream and radially inward from the frame, a follower roller fixed to the convergent petal on a radially outer side of the convergent petal, and a cam defining a working surface configured to engage the follower roller to react a force from the convergent petal. The cam is movable along a travel in an axial direction to actuate radial movement of the follower roller to pivot the convergent petal. The cam defines a concave working surface such that a contact angle between the follower roller and the cam varies along the travel to thereby vary a radial component of the force reacted by the cam.

Abstract: There is disclosed an exhaust nozzle for a gas turbine engine. The exhaust nozzle comprises a frame extending along a longitudinal axis, and a convergent petal pivotably attached at a convergent pivot point to the frame and extending axially downstream and radially inward from the frame. The exhaust nozzle comprises a follower roller fixed to the convergent petal on a radially outer side of the convergent petal, and a cam defining a working surface configured to engage the follower roller to react a force from the convergent petal. The cam is movable along a travel in an axial direction to actuate radial movement of the follower roller to pivot the convergent petal. The cam defines a convex working surface such that a contact angle between the follower roller and the cam varies along the travel to thereby vary an axial component of the force reacted by the cam.

Abstract: There is disclosed an exhaust nozzle for a gas turbine engine. The exhaust nozzle comprises a frame extending along a longitudinal axis, and a convergent petal pivotably attached at a convergent pivot point to the frame and extending axially downstream and radially inward from the frame. The exhaust nozzle comprises a follower roller fixed to the convergent petal on a radially outer side of the convergent petal, and a cam defining a working surface configured to engage the follower roller to react a force from the convergent petal. The cam is movable along a travel in an axial direction to actuate radial movement of the follower roller to pivot the convergent petal. The cam defines a convex working surface such that a contact angle between the follower roller and the cam varies along the travel to thereby vary an axial component of the force reacted by the cam.

Abstract: There is disclosed an exhaust nozzle for a gas turbine engine, the exhaust nozzle comprising a frame extending along a longitudinal axis. The exhaust nozzle comprises a convergent petal pivotably attached at a convergent pivot point to the frame and extending axially downstream and radially inward from the frame, a follower roller fixed to the convergent petal on a radially outer side of the convergent petal, and a cam defining a working surface configured to engage the follower roller to react a force from the convergent petal. The cam is movable along a travel in an axial direction to actuate radial movement of the follower roller to pivot the convergent petal. The cam defines a concave working surface such that a contact angle between the follower roller and the cam varies along the travel to thereby vary a radial component of the force reacted by the cam.

Abstract: Disclosed is an exhaust nozzle for a gas turbine engine, the exhaust nozzle comprising an outer frame extending along a longitudinal direction, a convergent petal pivotably attached to the frame and extending axially downstream and radially inward from the pivot, radially within the frame, and a sealing hinge arrangement between an upstream member and a downstream member of the exhaust nozzle. One of the upstream member or the downstream member defines a cylindrical socket having an opening along a cylinder axis which receives a corresponding cylindrical hinge element the other of the downstream member or upstream member, where the upstream member is defined by the frame and the downstream member is the convergent petal; or the exhaust nozzle further comprises a divergent petal downstream of the convergent petal and pivotably attached to the convergent petal, the upstream member being the convergent petal and the downstream member being the divergent petal.

Abstract: A nozzle for a gas turbine engine. An array of convergent petals hingedly coupled to a nozzle exit of fixed diameter. An array of divergent petals, each divergent petal hingedly coupled to one of the array of convergent petals. A cam surface associated with the array of convergent petals. A pivot point coupled to the array of divergent petals by a first linkage and to a fixed point by a second linkage. A cam follower coupled to the second linkage by a third linkage, the cam follower arranged to abut and travel in contact with the cam surface. An actuator coupled to the cam follower and arranged to translate the cam follower along the cam surface to move the convergent and divergent petals.

Abstract: A flap for a variable area exhaust nozzle of a gas turbine engine, having a support structure and a gas shield having a plurality of gas shield segments connected to the support structure and adjacently arranged along a longitudinal direction of the flap corresponding to flow through the nozzle. Each of the gas shield segments has a flowpath section arranged to cooperate with a corresponding flowpath section of an adjacent gas shield segment to define a flowpath surface of the gas shield to bound flow through the nozzle. The gas shield segments are configured to permit the respective flowpath section to move longitudinally relative the support structure in response to thermal expansion of the gas shield.

Abstract: A variable geometry exhaust nozzle arrangement includes a plurality of hingable exhaust petals defining a perimeter of an exhaust duct and an annular ring slidably engagable against a radially outer surface of each petal. The annular ring is coupled to a plurality of circumferentially spaced actuator arrangements, each including first and second circumferentially spaced parallel actuator arms pivotably coupled to the annular ring at a first end and to a slide arrangement at a second end. Each slide arrangement is mounted for linear sliding movement relative to the annular ring, such that sliding movement of each slide arrangement causes pivoting of the first and second actuator arms to thereby translate the annular ring in one or both of a longitudinal direction and a lateral direction.

Abstract: There is disclosed a flap for a variable area exhaust nozzle of a gas turbine engine. The flap comprises a support structure and a gas shield connected to the support structure, wherein the support structure is corrugated to accommodate thermal expansion of the gas shield in a direction of corrugation.

Abstract: A flap for a variable area exhaust nozzle of a gas turbine engine. The flap includes a support structure and a gas shield retained thereto. The support structure and the gas shield include a pair of grooves extending in a longitudinal direction of the flap and a pair of corresponding tongues that engage the pair of grooves so as to retain the gas shield to the support structure and to allow movement of the gas shield by thermal expansion along the support structure in the longitudinal direction.

Abstract: A nozzle for a gas turbine engine. An array of convergent petals hingedly coupled to a nozzle exit of fixed diameter. An array of divergent petals, each divergent petal hingedly coupled to one of the array of convergent petals. A cam surface associated with the array of convergent petals. A pivot point coupled to the array of divergent petals by a first linkage and to a fixed point by a second linkage. A cam follower coupled to the second linkage by a third linkage, the cam follower arranged to abut and travel in contact with the cam surface. An actuator coupled to the cam follower and arranged to translate the cam follower along the cam surface to move the convergent and divergent petals.

Abstract: A variable geometry exhaust nozzle arrangement includes a plurality of hingable exhaust petals defining a perimeter of an exhaust duct and an annular ring slidably engagable against a radially outer surface of each petal. The annular ring is coupled to a plurality of circumferentially spaced actuator arrangements, each including first and second circumferentially spaced parallel actuator arms pivotably coupled to the annular ring at a first end and to a slide arrangement at a second end. Each slide arrangement is mounted for linear sliding movement relative to the annular ring, such that sliding movement of each slide arrangement causes pivoting of the first and second actuator arms to thereby translate the annular ring in one or both of a longitudinal direction and a lateral direction.