SMArt Morphing Wing: um protótipo de asa adaptativa acionada por micromolas de liga com memória de forma.

Abstract

The development of the aeronautic industry has caused significant changes in concepts currently applied in aircraft either for civil or military purposes. These changes are partly due to environmental awareness that has pushed the industry to produce more efficient and less polluting aircraft to remain competitive. The result of these changes on design and construction of aircraft is the incessant search for concepts that increase the efficiency of aircraft in a broader flight range without impacting on the safety and reliability of these systems. In this context arises the concept of adaptive aircraft, which are able to adapt to the flow of aerodynamic changes without compromising flight safety. One of the concepts of morphing aircraft is the morphing wing, with the possibility of variation airfoil camber, which is used in this work. These structures have some limitations that need to be developed as the actuation system, control system and structural mechanics associated with the shape change. Based on these aspects, this work describes the development of a new concept of adaptive wing, driven by shape memory alloy (SMA) micro coil springs like actuator. The prototype, called SMArt Morphing Wing, had its mechanical structure built in ABS polymer for 3D printing and a system of "skin" made of thin sheet of acetate. The prototype was tested unloaded and under aerodynamic loading on the wind tunnel, to evaluate the influence of the skin and the response of SMA actuators under load. In the no load tests were evaluated the maximum angular deflection of the prototype with and without skin, whereas in tests under aerodynamic loading between 6m/s and 14m/s, the maximum deflection, drag and lift forces were evaluated. Additionally, using the computational tool ANSYS® CFD, theoretical analyses of the aerodynamic behavior of the prototype in the most critical condition deflection and speed they were made. The comparison between the numerical and experimental results obtained in wind tunnel showed good agreement, confirming the efficiency of the developed prototype.