| Ice accretions on aircraft components have severe and sometimes fatal effects. Aircraft wings are one of the many components that are prone to severe ice accretions. The de-icing/anti-icing technologies currently being used are bulky, cover the airfoil surface and consume high energies. Addressing these drawbacks, the current study proposes a novel de-icing technique utilizing lightweight piezoelectric actuators to break the weak adhesive shear bond of ice-substrate interface. When structures are excited at their natural frequencies, high shear stresses are generated in certain modes. These high shear stresses can break the weak adhesive shear bond of ice-substrate interface with minimal energy inputs. The proposed de-icing technique is applied on two structures, (1) a laminated composite cantilever rectangular plate, and (2) a prototyped aluminum leading edge. Theoretical investigations are fist performed to determine the frequencies and modes in which high amount of shear stresses and debonding of the ice layers occurred. After determining optimal actuator locations, experimental set-up is designed and structures are built. Experimentation of the proposed technique is carried out inside a freezer by forming two types of ice layers on the surfaces and exciting the structures to the determined frequencies. Testing is carried out at five different temperatures ranging from 5°F to 25°F. De-icing is observed for both types of ice layers in both the structures. While the average de-icing times increased with decreased temperatures, longer de-icing times are noted for the aluminum leading edge. In addition, energy requirements of the piezoelectric actuators to actuate an adaptive composite wing structure are evaluated and a composite material is designed to improve deicing of the leading edge. |
