UNSTEADY-FLOW CALCULATIONS WITH A MULTIGRID NAVIER-STOKES METHOD

A multigrid Navier-Stokes method with a two-equation k-omega turbulenc e model is developed for calculating unsteady flows, The method uses a staggered finite volume scheme to discretize the Navier-Stokes and th e turbulence model equations in space. A fully implicit time-accurate scheme is reformulated so that an efficient explicit multistage method with local time stepping, residual smoothing, and multigrid can be us ed to accelerate convergence within each unsteady time step, The metho d combines the advantages of implicit and explicit schemes for unstead y Bow calculations, Solutions for the forced oscillation of an airfoil are obtained with the Euler and the Navier-Stokes equations. Results are compared with experimental data.