摘要:
A gas turbine engine includes a variable area nozzle having a plurality of flaps. The flaps are actuated by a plurality of actuating mechanisms driven by shape memory alloy (SMA) actuators to vary fan exist nozzle area. The SMA actuator has a deformed shape in its martensitic state and a parent shape in its austenitic state. The SMA actuator is heated to transform from martensitic state to austenitic state generating a force output to actuate the flaps. The variable area nozzle also includes a plurality of return mechanisms deforming the SMA actuator when the SMA actuator is in its martensitic state.
摘要:
A variable exhaust nozzle (26) for a turbine engine nacelle (16) includes a pair of semi-cowls (58, 60) disposed about a longitudinally extending central axis (14) and a pair of corresponding shells (36, 38) each of which is spaced radially inwardly from the corresponding semi-cowl and is pivotable about a pivot axis (42, 44) between an extended position and a retracted position. The semi-cowls and shells have curved, geometrically similar inner and outer surfaces (86, 100) respectively so that gap (108) between the shells and the cowl is uniform irrespective of the angular orientation of the shells. A seal (128) which includes longitudinally extending legs (128a, 128b) and an optional circumferential leg (128c) prevents detrimental air leakage. Pivotal movement of the shells effects large changes in the discharge area A.sub.D of the nozzle without compromising the external aerodynamic characteristics of the nacelle. In one embodiment of the invention, each shell includes an extension (110) which facilitates the attainment of large area changes. The radial uniformity of gap (108) contributes to the durability and simplicity of the seal by ensuring that the seal is not repeatedly compressed and relaxed during operation of the nozzle.
摘要:
A flanged apparatus includes an apparatus body and a flanged mount, which includes a support pylon, a first mounting flange and a second mounting flange. The support pylon includes a first pylon segment, a second pylon segment and a routing notch. The first pylon segment is cantilevered from the apparatus body, and extends to the first mounting flange. The second pylon segment is cantilevered from the first pylon support, and extends from the first mounting flange to the second mounting flange. The routing notch extends vertically between the first pylon segment and the second pylon segment. The first mounting flange and the second mounting flange extend laterally from the support pylon, and the first mounting flange is separated from the second mounting flange by a longitudinal distance and a vertical distance.
摘要:
A linkage system includes a pivot bias assembly at each pivot which removes internal clearances and resultant vibratory wear. The pivot bias assembly includes a cavity which defines an axis transverse to the pivot axis. A spring biased piston is located therein to provide a radial load toward the rotation pivot to close radial clearances. The spring loaded piston reduces all the radial internal clearances to zero to reduce vibratory wear created by engine vibratory inputs. An assembly flat is positioned such that the component is assembled in a non-operating angular position such that the spring biased piston is under minimal or no load then the component is rotated into operating position so as to preload the spring biased piston.
摘要:
A nacelle and mounting arrangement for a high bypass ratio ducted fan aircraft engine mounted external to the aircraft main structure is disclosed. The nacelle and mounting arrangement isolate the engine from the adverse effects of certain aerodynamic forces acting on the nacelle by transferring substantially all of those forces directly from the nacelle to the aircraft and transferring substantially none of those forces to the engine. Various arrangements of the nacelle components which facilitate engine removal while avoiding the placement of nacelle component interfaces in highly stressed regions of the nacelle are also disclosed.
摘要:
A linkage system includes a pivot bias assembly at each pivot which removes internal clearances and resultant vibratory wear. The pivot bias assembly includes a cavity which defines an axis transverse to the pivot axis. A spring biased piston is located therein to provide a radial load toward the rotation pivot to close radial clearances. The spring loaded piston reduces all the radial internal clearances to zero to reduce vibratory wear created by engine vibratory inputs. An assembly flat is positioned such that the component is assembled in a non-operating angular position such that the spring biased piston is under minimal or no load then the component is rotated into operating position so as to preload the spring biased piston.
摘要:
A gas turbine engine (10) includes a translating sleeve (38) disposed within a downstream portion of an outer nacelle (20). A variable area fan exhaust nozzle (30) is defined between the trailing edge (32) of the translating sleeve (38) and a conical core cowl (26) disposed radially inwardly of the outer nacelle (20) and spaced apart therefrom. The translating sleeve (38) translates downstream to cooperate with the decreasing diameter of the core cowl (26) to increase the area of the fan exhaust nozzle (30).
摘要:
A flanged apparatus includes an apparatus body and a flanged mount, which includes a support pylon, a first mounting flange and a second mounting flange. The support pylon includes a first pylon segment, a second pylon segment and a routing notch. The first pylon segment is cantilevered from the apparatus body, and extends to the first mounting flange. The second pylon segment is cantilevered from the first pylon support, and extends from the first mounting flange to the second mounting flange. The routing notch extends vertically between the first pylon segment and the second pylon segment. The first mounting flange and the second mounting flange extend laterally from the support pylon, and the first mounting flange is separated from the second mounting flange by a longitudinal distance and a vertical distance.