Hi, I have what would be considered a very basic question. I am dealing with a relativistic blast wave explosion problem, that is described by the relativitsic hydrodynamic equations in one dimension. The computational region is split up into two states initially with higher pressure and density on the left and a lower pressure and density on the right. The velocity is zero on both sides. At t>0 obviously the fluid from the higher pressure region on the left flows into the lower pressure region on the right. This is exactly like the classical Sod Shock tube problem. Is there an expression to initate the flow and give a fluid velocity v>0? Other wise the finite differnece scheme that I am using just gives a zero velocity everywhere? Or am i missing something?

P.S. As you may ahve guessed I am very new to the field of computational fluid dynamics!!

read the numerical results of chapter 4 of this book;

Riemann Solvers and Numerical Methods for Fluid Dynamics.

Toro E F (1999). Springer-Verlag. Second Edition, June 1999, 624 pages.

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