Redeveloping Turbulent Boundary Layer in the Backward-Facing Step Flow

Abstract

An experimental study has been performed to investigate the redeveloping turbulent boundary layer beyond separation-reattachment for a transitional separated flow. By considering the distribution of the intermittency, it has been confirmed that the turbulent structure changes gradually from a mixing layer to a turbulent boundary layer downstream of reattachment. The balances of the respective terms in the turbulent kinetic energy transport equation are evaluated from the energy dissipation rate obtained through numerical integration of the second moment of the energy spectrum. These terms together with those in the shear stress transport equation indicate the recovery process of the redeveloping boundary layer from nonequilibrium to equilibrium.