Non-uniform grids in elbe

We recently tested and implemented a grid refinement strategy in the LBM solver elbe. First, the concept was tested in the two-dimensional singlephase module elbeSP2D. The velocity field of a 2D Karman Vortex Street at Re 500 is shown below. After a proper validation of the grid coupling, the interpolation routines will be included in all the remaining elbe modules, including those for free surface and multiphase flows.