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arXiv · 2001.08268

An asymptotic preserving semi-implicit multiderivative solver

Jochen Schütz·David C. Seal
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Abstract

In this work we construct a multiderivative implicit-explicit (IMEX) scheme for a class of stiff ordinary differential equations. Our solver is high-order accurate and has an asymptotic preserving (AP) property. The proposed method is based upon a two-derivative backward Taylor series base solver, which we show has an AP property. Higher order accuracies are found by iterating the result over a high-order multiderivative interpolant of the right hand side function, which we again prove has an AP property. Theoretical results showcasing the asymptotic consistency as well as the high-order accuracy of the solver are presented. In addition, an extension of the solver to an arbitrarily split right hand side function is also offered. Numerical results for a collection of standard test cases from the literature are presented that support the theoretical findings of the paper.

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Jochen Schütz, David C. Seal. 2020-01-22. An asymptotic preserving semi-implicit multiderivative solver. https://arxiv.org/abs/2001.08268

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