Lattice Boltzmann study on drag reduction of a bluff body by slip boundary

Abstract

Slip velocity at boundary will emerge when gas film or superhydrophobic coatings are applied to the surface. The no-slip boundary conditions are no longer efficient. In this work, an improved boundary treatment is proposed to obtain slip velocity. Numerical results of the Couette flow have verified the accuracy and reliability of the improved boundary condition. Taking into account the effect of boundary slip, the present research predicts the resistance of a bluff body under low Reynolds numbers using the lattice Boltzmann method. Results show that reasonable slip distribution may be favourable to the drag reduction effect.