Boundary layer over a slotted plate

In order to investigate the boundary layer over a slotted plate, we first set up a hydrodynamic boundary condition for a parallel flow from a numerical study, performed on a periodic perforated medium at the local scale of the perforations. This boundary condition links the shear stress at the wall and the slip velocity along the plate by a partial slip coefficient. Then, a parametric study is conducted to analyse this partial slip coefficient versus the surface porosity of the plate and the Reynolds number of the flow. Afterwards, we introduce this partial slip boundary condition in the Blasius formalism and express the dynamic boundary layer thickness, the reduced slip velocity and the shear stress at the wall as functions of the slip coefficient, the Reynolds number and the reduced abscissa on the plate. Finally, we compare these latter laws with direct simulation results of the boundary layer flow over a slotted plate, considered as a very thin homogeneous permeable flat wall. (C) Elsevier, Paris.