An experimental study on the thermal effects of duty-cycled plasma actuation pertinent to aircraft icing mitigation

An experimental study was performed to evaluate the effectiveness of utilizing the thermal effects induced by duty-cycled dielectric barrier discharge (DBD) plasma actuation for aircraft icing mitigation. The experimental study was carried out in the unique Icing Research Tunnel available at Iowa State University (i.e., ISU-IRT) with a NACA0012 airfoil model embedded with DBD plasma actuators exposed under a typical glaze icing condition. During the experiments, the DBD plasma actuators were operated in two different modes for a comparative study, i.e., in duty-cycled actuation mode vs. in conventional continuous actuation mode as the comparison baseline. While the anti-/de-icing performances of the DBD plasma actuators under different actuation modes were revealed clearly based on the snapshot images acquired by using a high-speed imaging system, an infrared (IR) thermal imaging system was also used to map the corresponding surface temperature distributions over the ice accreting airfoil surface in order to characterize the thermal effects induced by the plasma actuations. It was found that, with the same power input, the plasma actuation in duty-cycled mode would have a higher instantaneous voltage during the "on" periods, resulting in much stronger thermal effects for an improved anti-/de-icing performance, in comparison to the case in the continuous actuation mode. The thermal effects induced by the duty-cycled plasma actuation were found to be further enhanced by increasing of the modulating frequency of the duty cycles, which is a very promising approach to further improve the anti-/de-icing performance of DBD plasma actuation. The findings derived from the present study could be used to explore/ optimize design paradigm for the development of novel DBD-plasma-based anti-/de-icing strategies tailored specifically for aircraft icing mitigation. (C) 2019 Elsevier Ltd. All rights reserved.