Numerical Investigation on Drag Reduction Effect by Mass Injection from Porous Boundary Wall

Interaction between the injected flow from the porous wall and the main flow can reduce drag effectively. The phenomenon is significant to the flight vehicle design. The intensive flux of injection enhances difficulty of numerical simulation and requires higher demands on the turbulence model. A turbulent boundary layer flow with mass injection through a porous wall governed by Reynolds averaged Navier-Stokers (RANS) equations is solved by using the Wilcox's k-ω turbulence model and the obtained resistance coefficient agrees well with the experimental data. The results with and without mass injection are compared with other conditions unchanged. Velocity profile, turbulent kinetic energy and turbulent eddy viscosity are studied in these two cases. Results confirm that the boundary layer is blowing up and the turbulence is better developed with the aid of mass injection, which may explain the drag reduction theoretically. This numerical simulation may deepen our comprehension on this complex flow.