4 th SPHERIC workshop

In 2007, the results from a comparison study of grid based codes and SPH codes on multiphase interactions in compressible fluids were presented [1]. The main conclusion from this study was that whilst the grid codes are able to describe important dynamical instabilities, such as KelvinHelmholtz (KH) and Richtmyer-Meshkov (RM), these processes are poorly described by existing SPH codes. It was later shown [17] how the inclusion of artificial conductivity could bring major improvements to the SPH description of the KH instability. The aim of the current work is to compare different SPH formulations and different approaches to adding artificial dissipation on a selection of problems involving hydrodynamic instabilities. We use two widely different, state-of-the-art SPH codes in this study: One code is based on the Regularized SPH (RSPH) method [4] while the other code represents a more conventional approach to SPH [17] with the full “grad-h” formulation [12].