The efficient representation and handling of complicated geometries is one of the main challenges of today's numerical simulation. In the area of computational fluid dynamics, e.g., geometry plays a more and more predominant part. Especially for problems with moving interfaces, when we think of the cost of a successive remeshing in a finite element context, e.g., those geometric aspects seem to be at least as important as the construction of appropriate discretization schemes and solvers.

Against the background of these considerations, the codes NaSt2D and NaSt3D have been developed in order to allow flow simulations in the cases of complicated or moving geometries. In this paper, we want to report results from present fields of application showing the various improvements of the code that are necessary to achieve our aims.