contact problems for high accuracy Euler algorithm

igor

Dear colleagues! I have a question. There is CFD program: Eulerian, TVD, third- order space accuracy (with limiter), calculating dynamics of two layers of different fluids (Raleigh-Tailor instability). Incompressibility of fluids is modeling by high velocity of sound. Pressure is calculated by using of concentration (C=0 or C=1 for different fluids). Problem is: how to modify such algorithm to avoid accounting diffusion and to trace contact boundary (desirable without loss of accuracy). Also I need information about possibility to generalize this program for ALE, moving meshes. If you know situation in this area (publications, computer programs, problems and achievements) or if you can help me by any advise, I will be very grateful. Best wishes! Igor.