Exact Riemann Solver


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Contact: F.X.Timmes
my one page vitae,
full vitae,
research statement, and
teaching statement.

The tool exact_riemann.tbz solves the Riemann problem of a discontinuity across an interface. This tool is originally from Bruce Fryxell.

While the Sod problem has become a standard hydrodynamic test case, it isn't a very discriminating test for modern software instruments. The strong shock tube problem below is more demanding because of the stronger discontinuities across the shock interface and the narrow density peak that forms behind the shock. The γ=1.4 test case sets the initial density to $\rho =10$ for $x < 2$, $\rho = 1$ for $x > 2$, and the initial pressure to $P =100$ for $x < 2$, $P = 1$ for $x > 2$.

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For simple 1D hydrodynamics, see this PPM tool. For a reasonably modern hydrodynamics software instrument, check out FLASH. Mike Zingale's codes page offers several lovely open-source hydrodynamic tools for research and teaching.

Please cite the relevant references if you publish a piece of work that use these codes, pieces of these codes, or modified versions of them. Offer co-authorship as appropriate.