Homayoon ESHRAGHI
Institute for Studies in Theoretical Physics and Mathematics (IPM),
Farmanieh Building, Farbin Str., Farmanieh Str.,
P.O. Box: 19395-5531, Tehran, IRAN
E-mail: eshraghi@ipm.ir

On the double Riemann wave solutions in nonrelativistic and relativistic fluids

Abstract:
Usual Riemann wave is an exact one dimensional solution of fluid equations. A first generalization of this solution is a multidimensional simple wave. A further non-trivial generalization is a double wave in which there are two coupled but independent phases. In this work a development of this solution is given to obtain the time of discontinuity formation. In presenting this solution for relativistic flows, it is demonstrated the initial conditions must satisfy a specific equation. Also the existence of Riemann invariants is investigated through characteristic surfaces.