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Relativistic MHD with Adaptive Mesh Refinement

Matthew Anderson·Eric Hirschmann·Steven L. Liebling·David Neilsen
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Abstract

This paper presents a new computer code to solve the general relativistic magnetohydrodynamics (GRMHD) equations using distributed parallel adaptive mesh refinement (AMR). The fluid equations are solved using a finite difference Convex ENO method (CENO) in 3+1 dimensions, and the AMR is Berger-Oliger. Hyperbolic divergence cleaning is used to control the $\nabla\cdot {\bf B}=0$ constraint. We present results from three flat space tests, and examine the accretion of a fluid onto a Schwarzschild black hole, reproducing the Michel solution. The AMR simulations substantially improve performance while reproducing the resolution equivalent unigrid simulation results. Finally, we discuss strong scaling results for parallel unigrid and AMR runs.

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Matthew Anderson, Eric Hirschmann, Steven L. Liebling, David Neilsen. 2006-10-11. Relativistic MHD with Adaptive Mesh Refinement. https://doi.org/10.1088/0264-9381%2F23%2F22%2F025

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