Empirical correlations in B-C transition model were calibrated with experimental values of zero pressure gradient plates. Calibrated B-C transition model predicts reasonably transition positions with low inlet turbulence intensity. However, due to limitations of RANS method, B-C transition model’s accuracy diminishes for massively separated flows. A turbulence closure named transitional Delayed Detached-Eddy Simulation (BC-DDES) method is proposed which combines traditional SA-DDES method and B-C transition model. This method has the potential for accurately capturing massively separated boundary layers in transitional Reynolds number range. Numerical simulation of three-dimensional S-K flat plate shows that BC-DDES method obtains transition prediction consistent with baseline transition model. Comparisons are evaluated on circular cylinder in crossflow. It shows that pressure distribution and drag coefficient of cylinder calculated with BC-DDES method agree well with experimental data, with less computational costs than tHRLES method.

With a fifth-order weighted compact nonlinear scheme(WCNS-E-5),flow field of a 65° delta wing with sharp leading edges at high angles of incidence is simulated.The target is checking WCNS's ability for vortex flow at high angles of incidence and vortex breakdown location with shock-vortex interaction.We focus on sudden jump in breakdown towards apex.Unsteady Reynolds averaged Navier-Stokes(URANS) method is available including a high-order weighted compact nonlinear scheme and an SST turbulence model.It is shown that the high order scheme(WCNS-E-5) with minimum numerical dissipation and could capture discontinuities for high angles of incidence transonic flow of delta wing and the results are matched satisfactorily with experiments.Shock-vortex interaction in transonic freestream explains sudden movement of vortex breakdown as the angle of incidence is increased.

Navier-Stokes calculation on multi-block is performed to calculate drag of the DLR-F6 wing-body configuration with CFD software TRIP2.0.Structured grids(1-to-1) and test results used are from Drag prediction workshop Ⅱ (DPWⅡ). Referenced numerical results are obtained with CFL3D. Effects of mesh density and turbulent models on aerodynamic characteristics and pressure distribution are carefully studied. Results are verified by experimental data and CFL3D results. Grid refinement leads to convergent results in SST turbulent models. It is demonstrated that turbulent models have little influence on pressure drag, but obvious influence on friction drag. The turbulent model and grid density have little influence on pressure distribution.