抄録
For practical CFD-aided design of riblets on aircrafts, we are aiming to develop a Reynolds-Averaged Navier-Stokes (RANS) turbulence model which can simulate drag reduction effects without resolving fine-scale flows near the riblets. Wilcox's rough wall boundary condition for Menter's SST model is modified to reproduce velocity shift in logarithmic region corresponding to riblet's drag reduction effects. Two basic relations for this model are derived from available experimental data and parametric analysis, and are validated in zero-pressure gradient boundary layers with two different-geometry riblets. Drag reduction rates corresponding to experimental results can be obtained with these relations. The new model, however, underestimates the effects of riblet mounted on NACA0012, which suggests that further improvement of the model is needed to account for influences of pressure gradient.
