Shape Memory Alloy Actuation System for Variable Area Fan Nozzle
AssigneeThe Boeing Company
InventorChristopher T. Jasklowski
Life of this patent
Estimating the term…
Abstract
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.
Claims20
A variable area fan nozzle comprising:
- a support member having a curved shape;
- first and second petals coupled to said support member in a manner that allows each of said first and second petals to deflect inwardly or outwardly, said first and second petal being separated by a gap;
- and
- a first body comprising a first portion that spans said gap, and second and third portions connected to said first portion and respectively attached to said first and second petals, wherein said first portion is made of shape memory alloy having the characteristic that it undergoes a first shape change when its temperature is increased from below to above a transition temperature, wherein said first body is arranged to deflect said first and second petals when said first portion of said first body undergoes said first shape change.
A method for varying an exit area of a nozzle, comprising increasing the temperatures of respective portions of a first plurality of elements from below to above a transition temperature, said respective portions of said first plurality of elements being made of shape memory alloy that changes shape during an increase in temperature from below to above said transition temperature.
A variable area fan nozzle comprising:
- a plurality of petals which can be deflected inwardly or outwardly in unison;
- and
- a first plurality of petal deflection actuators attached to said petals, wherein each petal deflection actuator of said first plurality comprises shape memory alloy that changes shape when its temperature is increased from below to above a transition temperature, which shape changes in said first plurality of petal deflection actuators cause said petals to deflect.
An apparatus installed on an aircraft, comprising:
- a sleeve or duct having a trailing lip area comprising a support member having a curved shape;
- a plurality of petals coupled to said support member in a manner that allows each petal to deflect inwardly or outwardly, wherein adjacent petals are separated by respective gaps;
- a plurality of deformable elements distributed in said gaps, each deformable element comprising shape memory alloy that changes shape when heated to a temperature above a transition temperature;
- a plurality of electric heaters thermally coupled to respective surfaces of said deformable elements;
- and
- a computer system programmed to control the supply of electrical power to said electric heaters.
Dependencies are inferred from the claim text.