Direct Numerical Simulation of Jet in Crossflow actuators

Jet vortex generators have been proven to provide a mechanism to positively control boundary layer flows. The present paper illustrates a method to perform direct numerical simulations (DNS) of a jet actuator flow inside a laminar boundary layer. A structured finite difference method is used for the simulations. The numerical scheme was adapted to account for the large scale differences both in geometric and fluid dynamic aspects. Analytical mesh transformations have been implemented to resolve the jet orifice. Suitable boundary conditions are established to model the jet flow. Arising numerical instabilities have been suppressed by implementing a compact filter scheme. Test simulations are done for jet actuator configurations in laminar baseflow with jet to freestream velocity ratios of up to R = 3.0. The computational effort on a NEC SX 8/9 is also investigated.