Multigrid Computation of Incompressible Flows Using Two-Equation Turbulence Models: Part I—Numerical Method

A highly efficient numerical approach based on multigrid and preconditioning methods is developed for modeling 3-D incompressible turbulent flows. The incompressible Reynolds-averaged Navier-Stokes equations are written in pseudo-compressibility from, then a preconditioning method is used to reduce the wave speed disparity. The k-ω and k-ε turbulence models are used to estimate the effects of turbulence. The model equations are solved together with the N-S equations in a strongly-coupled way, and all the acceleration techniques originally developed for N-S equations are also used for the turbulence model equations. A point-implicit technique is developed to improve the efficiency of the solution of the turbulence model equations.