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The Adverse Environment Rotor Test Stand (AERTS) was designed to reproduce icing clouds surrounding a 9 feet diameter hovering rotor. During prior studies, it was demonstrated that the facility can reproduce representative icing clouds. In this research, ice shapes obtained on NACA 0012 rotor blades are compared to wind tunnel results presented in the literature. The aim of the effort is to validate the capability of the facility to reproduce icing conditions on lifting rotors. Ice shapes were recorded digitally by means of 2D photograph and 3 dimensional laser scanning techniques and compared to those obtained at the NASA Glenn Icing Research Tunnel (IRT). Good agreement between ice shapes measured in the AERTS and the NASA IRT was found. Unique features of rotor icing were successfully identified and reproduced.

Ultrasonic excitation has proven to provide ice interface transverse shear stresses exceeding the adhesion strength of freezer and wind tunnel ice to various metals, promoting instantaneous ice delamination. Prior proof-of-concept testing presented issues related to piezoelectric actuator cracking under ultrasonic tensile excitation, as well as actuator debonding from the host structure. The aim of this research is to provide solutions to the actuator reliability issues encountered during prior research and to perform rotor icing testing to validate the proposed solutions. Three different approaches are taken to solve the issues related with actuator failure during de-icing processes: custom-designed controllers to ensure the excitation of desired ultrasonic resonance modes, compression only driving of the actuator, and optimization of actuator thickness.