Comparison of two Navier-Stokes codes for simulating high-incidence vortical flow

Computations from two Navier-Stokes codes, NSS and F3D, are presented for a tangent-ogive cylinder body at high angle of attack. Features of this steady flow include a pair of primary vortices on the leeward side of the body, as well as secondary vortices. The topological and physical plausibility of this vortical structure is discussed. The accuracy of these codes are assessed by comparison of the numerical solutions with experimental data. The effects of turbulence model, numerical dissipation, and grid refinement are presented. The overall efficiency of these codes are also assessed by examining their convergence rates, computational time per time step, and maximum allowable time step for time-accurate computations. Overall, the numerical result from both codes compared equally well with experimental data, however, the NSS code was round to be significantly more efficient than the F3D code.