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arXiv · 2012.11130

An adaptive mesh, GPU-accelerated, and error minimized special relativistic hydrodynamics code

Po-Hsun Tseng·Hsi-Yu Schive·Tzihong Chiueh
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Abstract

We present a new special relativistic hydrodynamics (SRHD) code capable of handling coexisting ultra-relativistically hot and non-relativistically cold gases. We achieve this by designing a new algorithm for conversion between primitive and conserved variables in the SRHD solver, which incorporates a realistic ideal-gas equation of state covering both the relativistic and non-relativistic regimes. The code can handle problems involving a Lorentz factor as high as $10^6$ and optimally avoid the catastrophic cancellation. In addition, we have integrated this new SRHD solver into the code GAMER (https://github.com/gamer-project/gamer) to support adaptive mesh refinement and hybrid OpenMP/MPI/GPU parallelization. It achieves a peak performance of $7\times 10^{7}$ cell updates per second on a single Tesla P100 GPU and scales well to 2048 GPUs. We apply this code to two interesting astrophysical applications: (a) an asymmetric explosion source on the relativistic blast wave and (b) the flow acceleration and limb-brightening of relativistic jets.

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Po-Hsun Tseng, Hsi-Yu Schive, Tzihong Chiueh. 2020-12-21. An adaptive mesh, GPU-accelerated, and error minimized special relativistic hydrodynamics code. https://doi.org/10.1093/mnras/stab1006

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