DISPERSION AND VISCOSITY IMPACT ON EXPANSION SHOCKS PARAMETERS FOR GENERAL NONCONVEX EQUATION OF STATE
Yu. A. Bondarenko, V. N. Sofronof, Yu. E. Dudnik VANT. Ser.: Mat. Mod. Fiz. Proc 2013. Вып.1. С. 317.
The admissibility conditions of expansion shocks were obtained in the case of general equation of state with nonconvex insentropy with normal dispersion as a main process smearing the jump out, and with no viscosity. They differ from admissibility condition of shocks at the defining role of viscosity. For Bizarrium problem with nonconvex equation of state the exact disperse solution is given for the disperse condition of expansion shocks admissibility differing from the viscous exact solution with admissibility viscous condition of expansion shocks obtained by O. Heuz´e, S. Jaouen, H. Jourdren. The computations showed that grid refinement numerical solutions approximate the viscous exact solution when using the dominating expansion viscosity, and in case of its absence the solutions approximate the disperse exact solution. It may be concluded that the selection problem of the only and “correct” expansion shock in gas dynamics computations should be solved at the level of physical models selection in terms of the main physical processes to be omitted for the ideal gas dynamics equations.Keywords: expansion shocks, admissibility conditions, viscosity, dispersion, selfsimilar solution, numerical convergence.
