Implementation of a Dual-Time Stepping Method for the Numerical Solution of N-S Equations for Rigid Airfoils in Arbitrary Unsteady Motion

Kurzfassung

Based on an existing code for the solution of two-dimensional unsteady Navier-Stokes equations using a five-stage Runge-Kutta explicit time stepping scheme, a code with an implicit time discretization scheme using the dual-time stepping method is developed in order to reduce the large CPU time which is needed by the explicit method. A multigrid algorithm is applied in order to increase the efficiency of the dual-time stepping method. One numerical example for pitching oscillation at small angle of attack is given, and is compared with the results of the explicit code. The efficiency of the dual-time stepping method is demonstrated by the fact that the CPU-time for this testcase was reduced by a factor of more than 15.