Convergence acceleration by varying time-step size using Bi-CGSTAB method for turbulent flow computation

A design of varying step size approach both in time span and spatial coordi nate systems to achieve fast convergence is demonstrated in this study. Thi s method is based on the concept of minimization of residuals by the Bi-CGS TAB algorithm, so that the convergence can be enforced by varying the time- step size. The numerical results show that the time-step size determined by the proposed method improves the convergence rate for turbulent computatio ns using advanced turbulence models in low Reynolds-number form, and the de gree of improvement increases with the degree of the complexity of the turb ulence models. (C) 2001 John Wiley & Sons, Inc.