Strouhal number effects on pulsating synthetic jet’s entrainment

In the context of the active flow control of a massively separated flow through synthetic pulsed jets, the ability to determine a correspondence between the pulsation and the desired mean velocity is of prime interest and a crucial target. In the present work, an approach based on the actual mean speed and the entrained fluid in the jet is proposed using the state-of-the-art entrainment rate metrics in the evaluation. In particular, numerical simulations of a representative simplified case are performed in several conditions; the analyses are carried out using a commercial CFD solver by solving both the steady and unsteady Reynolds-Averaged Navier-Stokes system of equations closed by k − ω SST turbulence model. The study aims at determining the equivalent steady jet that provides similar entrainment effects of an unsteady setup.