Towards optimal plasma actuator arrays for friction drag reduction

An optimization framework for the design of an array of DBD plasma actuators to be eventually used for friction drag reduction from turbulent flows is presented. To investigate the plasma induced flow and eventually their effect on the incoming flow, high fidelity simulations were performed. The actuators were modeled according to body force distributions well documented in the literature. The aim of the work is to explore how different geometrical and operational parameters of the PA array affect the induced flow. First, in the optimization iterations, laminar flow simulations are carried out in order to recreate a Stokes-like flow, which can compensate for the known drag-enhancing effect caused by the plasma-jets induced downwash. Then, the effect of the optimized configuration forcing is assessed on a turbulent channel flow at Re_τ = 250. Eventually, also the effect of the incoming flow on the plasma-induced flow is evaluated.