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arXiv · 1512.03662

A Jacobian-free Newton-Krylov method for time-implicit multidimensional hydrodynamics

Maxime Viallet·Tom Goffrey·Isabelle Baraffe·Doris Folini·Chris Geroux·Mikhail Popov·Jane Pratt·Rolf Walder
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Abstract

This work is a continuation of our efforts to develop an efficient implicit solver for multidimensional hydrodynamics for the purpose of studying important physical processes in stellar interiors, such as turbulent convection and overshooting. We present an implicit solver that results from the combination of a Jacobian-Free Newton-Krylov method and a preconditioning technique tailored to the inviscid, compressible equations of stellar hydrodynamics. We assess the accuracy and performance of the solver for both 2D and 3D problems for Mach numbers down to $10^{-6}$. Although our applications concern flows in stellar interiors, the method can be applied to general advection and/or diffusion-dominated flows. The method presented in this paper opens up new avenues in 3D modeling of realistic stellar interiors allowing the study of important problems in stellar structure and evolution.

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Maxime Viallet, Tom Goffrey, Isabelle Baraffe, Doris Folini, Chris Geroux, Mikhail Popov, Jane Pratt, Rolf Walder. 2015-12-14. A Jacobian-free Newton-Krylov method for time-implicit multidimensional hydrodynamics. https://doi.org/10.1051/0004-6361%2F201527339

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