Velocity and pressure fields of SWBLIs on porous plates

The paper investigates the application of wall porosity for controlling the interaction between an impinging oblique shock wave and a turbulent boundary layer. This type of passive control aims to smear out the shock system in the longitudinal extent, thus inducing a more gradual pressure rise over the shock system with associated decrease of shock losses. Flow velocity measurements with PIV have been enhanced with pressure field information, obtained from integration of the governing equations. It is observed that the porosity indeed results in an extension of the upstream influence and, hence, increases the interaction length. Furthermore, the separation tendency in the interaction is increased, while the pressure rise inside the flow field is reduced. These effects increase in strength with porosity level, as expected, but are found to decrease with increasing hole diameter.