Computation of flow past a flat plate with porous trailing edge using a penalization method

In this study, flow past a flat plate with porous trailing edge is investigated using the penalization method. The incompressible Navier–Stokes equations are penalized with linear and non-linear drags and the computations are carried out with a high-order numerical scheme combined with a selective spatial filtering technique. To assess the validity of the present penalization method, the aerodynamic performance of a porous plate is investigated for different porosities and pore structures, in particular the predicted relationships between pressure drop and transpiration velocity are compared with those of direct flow simulation. Then, the effect of passive porous surfaces on the pressure field is investigated by considering the flow over a flat plate with perforated surfaces at Reh=1000Reh=1000. The computed result shows that a passive form of time-dependent blowing and suction along the perforated surface breaks the spatially coherent pressure field, and as a consequence, reduces drag and lift forces, including alteration of Kármán vortex shedding frequency. The importance of a non-linear drag term on determination of permeability is also demonstrated with discussion of Darcy and non-Darcy regimes.

► Effects of porous trailing edge are investigated for laminar flow over a flat plate.
► A penalization method is validated against the direct flow simulation.
► Role of transpiration flow and impact of streamwise extent are demonstrated with discussion of non-linear drag effect.