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arXiv · 2203.05176

Stability of structure-aware Taylor methods for tents

Jay Gopalakrishnan·Zheng Sun
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Abstract

Structure-aware Taylor (SAT) methods are a class of timestepping schemes designed for propagating linear hyperbolic solutions within a tent-shaped spacetime region. Tents are useful to design explicit time marching schemes on unstructured advancing fronts with built-in locally variable timestepping for arbitrary spatial and temporal discretization orders. The main result of this paper is that an $s$-stage SAT timestepping within a tent is weakly stable under the time step constraint $\Delta t \leq Ch^{1+1/s}$, where $\Delta t$ is the time step size and $h$ is the spatial mesh size. Improved stability properties are also presented for high order SAT time discretizations coupled with low order spatial polynomials. A numerical verification of the sharpness of proven estimates is also included.

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Jay Gopalakrishnan, Zheng Sun. 2022-03-10. Stability of structure-aware Taylor methods for tents. https://arxiv.org/abs/2203.05176

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