摘要 |
A variable area fan nozzle comprising an array of hinged rigid petals and a petal actuation system in which the principle of actuation is realized by changes in shape (i.e., deformation) of the actuators rather than by movement of cooperating mechanical parts. Because these actuators have no rotating or sliding mechanical components, wear and associated maintenance are reduced. Each deformable actuator has a portion made of shape memory alloy that has been trained to change shape in a specific manner when heated to a temperature above a transition temperature. In addition, each shape memory alloy actuator is shaped to act as a fairing to reduce aerodynamic drag. |