Multi-domain parallel computation of wake flows

We present a new, multi-domain parallel computational method for simulation of unsteady flows involving a primary object, a long wake region and, possibly, a secondary object affected by the wake flow. The method is based on the stabilized finite element formulation of the time-dependent Navier-Stokes equations of incompressible flows. In the multi-domain computational method the entire simulation domain is divided into an ordered sequence of overlapping subdomains. The flow data computed over the leading subdomain is used for specifying the inflow boundary conditions for the next subdomain. The subdomain corresponding to the wake would not involve any objects, hence the mesh constructed over this domain would be structured. A special-purpose finite element implementation for structured meshes is used for the wake domain to achieve much higher computational speeds compared to a general-purpose implementation. We present verification studies for the multi-domain method and special-purpose implementation, followed by two numerical examples. The first example is the wake behavior behind a circular cylinder. The second one is the aerodynamic effect of tip vortices released from a leading wing on a trailing wing placed in the far wake.