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arXiv · 2005.06651

The Athena++ Adaptive Mesh Refinement Framework: Design and Magnetohydrodynamic Solvers

James M. Stone·Kengo Tomida·Christopher J. White·Kyle G. Felker
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Abstract

The design and implementation of a new framework for adaptive mesh refinement (AMR) calculations is described. It is intended primarily for applications in astrophysical fluid dynamics, but its flexible and modular design enables its use for a wide variety of physics. The framework works with both uniform and nonuniform grids in Cartesian and curvilinear coordinate systems. It adopts a dynamic execution model based on a simple design called a "task list" that improves parallel performance by overlapping communication and computation, simplifies the inclusion of a diverse range of physics, and even enables multiphysics models involving different physics in different regions of the calculation. We describe physics modules implemented in this framework for both non-relativistic and relativistic magnetohydrodynamics (MHD). These modules adopt mature and robust algorithms originally developed for the Athena MHD code and incorporate new extensions: support for curvilinear coordinates, higher-order time integrators, more realistic physics such as a general equation of state, and diffusion terms that can be integrated with super-time-stepping algorithms. The modules show excellent performance and scaling, with well over 80% parallel efficiency on over half a million threads. The source code has been made publicly available.

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James M. Stone, Kengo Tomida, Christopher J. White, Kyle G. Felker. 2020-05-13. The Athena++ Adaptive Mesh Refinement Framework: Design and Magnetohydrodynamic Solvers. https://doi.org/10.3847/1538-4365%2Fab929b

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