Dual-Time Stepping Method

Abstract

The prediction of unsteady air-loads on airfoils and wings plays an increasing role in the aircraft design process. Hence,it is essential to develop numerical schemes which provide time accurate solutions at reasonable costs. An efficient implicit approach is the dual-time stepping method, which uses the physical time and a pseudo time. This approach is stable for arbitrary small and large physical time steps. The physical time steps are thus restricted only by accuracy requirements. In this section we will describe how the dual-time stepping approach has been integrated into the FLOWer code for the unsteady Navier-Stokes equations. We will demonstrate for a typical example that the combination of the implicit dual-time stepping method and the parallelization is a very efficient approach to predict unsteady viscous flows.