DNS of drag-reducing turbulent boundary layer flow with concentration variation of viscoelastic fluid

Abstract

We performed direct numerical simulations of turbulent boundary layer flows of viscoelastic fluids with taking into account the additive concentration variation where the viscoelastic behavior is represented by using the FENE-P model. In the present simulations, the initial and boundary conditions were set such that the additives were injected from the wall surface. We compared the diffusion processes between Newtonian and drag-reducing viscoelastic fluids for the Schmidt number Sc = 1, 5 and 10 at the momentum Reynolds number Re_θ0 = 670. In addition, the difference in local drag reduction ratio along the streamwise direction between homogeneous and inhomogeneous viscoelastic fluids was investigated at the Weissenberg number Wi = 50.