Aeroacoustic predictions in complex geometries

The simulation of sound generating flows in complex geometries requires accurate numerical methods that are non-dissipative and stable, and well-posed boundary conditions. A structured mesh approach is often desired for a higher-order discretization that better uses the provided grids, but at the expense complex geometry capabilities. One solution is to use an overset mesh based discretization where locally structured meshes are globally assembled in an unstructured manner. This article discusses recent advancements in overset, also called Chimera, methods concerning boundary conditions, parallel methods for overset grid management, and stable and accurate interpolation between grids. Several examples are given, some of which include moving grids.