Piecewise Parabolic Method (PPM)


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

The tool ppm.tbz is a simplified 1D PPM hydrodynamics solver on Cartesian grids. 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 $x > 2$. Below, the PPM solution and the exact solution to the exact Riemann solution at 0.4 s are compared.

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For a reasonably modern hydrodynamics software instrument with more capabilities (e.g., a more general equation of state or nuclear reaction networks, check out FLASH. Mike Zingale's codes page offers several lovely open-source hydrodynamic tools for research and teaching. Also see Mike's Zingale's hydro1d github project. For open, modern, multi-physics, multi-scale, and multi-dimensional hydrodynamic instruments, check out CASTRO, MAESTO, PHANTOM, and DEDALUS.

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.