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arXiv · 1206.5972

On numerical relativistic hydrodynamics and barotropic equations of state

J. M. Ibáñez·I. Cordero-Carrión·J. A. Miralles
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Abstract

The characteristic formulation of the relativistic hydrodynamic equations (Donat et al 1998 J. Comput. Phys. 146 58), which has been implemented in many relativistic hydro-codes that make use of Godunov-type methods, has to be slightly modified in the case of evolving barotropic flows. For a barotropic equation of state, a removable singularity appears in one of the eigenvectors. The singularity can be avoided by means of a simple renormalization which makes the system of eigenvectors well defined and complete. An alternative strategy for the particular case of barotropic flows is discussed.

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J. M. Ibáñez, I. Cordero-Carrión, J. A. Miralles. 2012-06-27. On numerical relativistic hydrodynamics and barotropic equations of state. https://doi.org/10.1088/0264-9381%2F29%2F15%2F157001

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