Modelling Ehd Actuation with a Slip Velocity

1. A. GRONSKIS, R. SOSA, AND G. ARTANA

Boston, MA, USA

Conferencia; Joint ESA/IEEE-IAS/IEJ/SFE/IEA Conference; 2009

ESA/IEEE-IAS/IEJ/SFE/IEA

The introduction of an electro-hydrodynamic (EHD) force in high performance numerical simulation may pose some problems as a consequence of the large differences between time or spatial scales of the physics of the discharge and those of interest for the fluid flow description. In this paper, we try to simplify this problem by looking for a correspondence between the global flow modifications produced by an EHD actuation and the one obtained by imposing locally a moving body surface. Thus direct numerical simulations (DNS) of the flow with slip velocities in correspondence with electrodes placements are performed. For a flow regime corresponding to Reynolds number based on the cylinder diameter and free-stream velocity of the flow of 125 (wake-transition regime), the simulations allow us to make a comparison with particle image velocimetry (PIV) measures of the flow induced by a dielectric barrier discharge (DBD) plasma actuator suitable disposed on the cylinder surface. The results obtained from the analysis of mean velocity fields show that the time-averaged vortical structures in the two cases enable us to establish a good analogy between actuations produced by both mechanisms. This kind of formulation enables the analysis of effects of actuators placement and distribution.