The Riemann Problem for a Binary Non-Reacting Mixture of Euler Fluids

The Riemann problem for a binary mixture of Euler fluids without chemical reaction is numerically studied. This system is a particular case of hyperbolic systems with relaxation and the interest of such analysis could be found in the fact that, since now, there is no systematic theory about Riemann problem for this kind of equations. For relaxation terms not too big, we found that the solutions of this Riemann problem are a composition of shocks, constant states and "deformed" rarefaction waves. It was already shown that the mixture model is simplified under the strong assumption that the constituent fluids have equal masses. The validity of this approximation is also studied for different binary mixtures.