Numerical simulation of an adaptive airfoil system using SMA actuators

Shape memory alloy (SMA) is lightweight, produces high force and large deflection which makes it a suitable candidate for actuator in the adaptive airfoil system design. The deflection of a variable cambered wing is controlled by means of resistive heating of SMA actuator and cooling in the surrounding air. An experimental wing model was developed using ABS to test the application of the SMA actuators. The SMA actuators were fixed underneath the wing skin. The heating of the wires caused them to contract, creating a force and generating a moment which deflects the wing. A wind tunnel test was performed to investigate the change in lift to drag ratio of the wing when the actuator is switched on and off. The results proved that the use of ABS skin and SMA actuators in the wing model is reliable as significant change in lift to drag ratio was detected when the wing was morphed.