Derivation of a Plasma-Actuator Model Utilizing Quiescent-Air PIV Data

The present work is concerned with development of a new model for the momentum transfer due to plasmaactuator in aerodynamic flow-control applications. A comparative analysis of different volume-force estimation strategies is provided, focussing particularly on the phenomenological and experiment-based approaches. The main objective of the present study is a comprehensive evaluation of these models aiming at derivation of a new model formulation of improved accuracy. All models are implemented into the OpenFOAM code. The models are validated within the RANS framework applied under the quiescent-air conditions by solving the Reynolds equations, closed by a near-wall second-moment closure model based on the homogeneous dissipation rate of the kinetic energy of turbulence. The computationally obtained velocity distribution induced by the wall-mounted plasma actuator is analyzed within the wall-jet flow region along with the experimental PIV data of identical actuator operating conditions. The results demonstrate the improved accuracy of the new empirical model as a first step towards a universal plasma-actuator model for flow-control simulations by means of CFD. 1 BACKGROUND AND MOTIVATION Plasma actuator for the aerodynamic flow control describes a DBD-based actuator (DBD: dielectric barrier discharge) generating an electric discharge between two parallel electrodes separated by an insulating dielectric material (barrier): a grounded electrode and the radio-frequency high-voltage one the upper surface of the latter being coincident with the wall surface. Consequently an electric field originating from the exposed high-voltage electrode will ionize weakly the surrounding air (surface plasma generation) and inHV (a) quiescent air HV