Application of an implicit dual-time stepping multi-block solver to 3D unsteady flows

Publisher Summary The chapter presents the application of a parallel, unfactored, implicit method for the solution of the three-dimensional (3D) unsteady Euler/Navier–Stokes equations on multiblock structured meshes. For time-accurate simulations, dual time-stepping is used. Many of the present computational fluid dynamics (CFD) applications in aerospace engineering involve unsteady three-dimensional (3D) aerodynamic problems. In contrast to steady state flows that can typically be tackled in a matter of hours on a multiprocessor machine or on a Beowulf cluster, unsteady flows require days of CPU time. The application of a parallel implicit multiblock CFD method to two challenging problems in aerodynamics is presented in the chapter. The computer platforms used here are a Beowulf cluster and the HPCx supercomputer. Obtained results indicate that parallel implementation of the solver is both robust and efficient on both platforms. The problems considered in the chapter include the transonic cavity flow and the flow around a helicopter rotor in forward flight. Using a Beowulf cluster, these flows can be analyzed using CFD simulations. The run times, however, become excessive if the details of the turbulent flow must be resolved using large-eddy simulation (LES) or detached-eddy simulation (DES).