Reflection-free finite volume Maxwell's solver for adaptive grids

Nina Elkina; Hartmut Ruhl

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arXiv · 1511.04994

Reflection-free finite volume Maxwell's solver for adaptive grids

Nina Elkina·Hartmut Ruhl

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Abstract

We present a non-staggered method for the Maxwell equations in adaptively refined grids. The code is based on finite volume central scheme that preserves in a discrete form both divergence-free property of magnetic field and the Gauss law. High spatial accuracy is achieved with help of non-oscillatory extrema preserving piece-wise or piece-wise-quadratic reconstructions. The semi-discrete equations are solved by implicit-explicit Runge-Kutta method. The new adaptive grid Maxwell's solver is examined based on several 1d examples, including the an propagation of a Gaussian pulse through vacuum and partially ionised gas. Two-dimensional extension is tested with a Gaussian pulse incident on dielectric disc. Additionally, we focus on testing computational accuracy and efficiency.

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Nina Elkina, Hartmut Ruhl. 2015-11-16. Reflection-free finite volume Maxwell's solver for adaptive grids. https://arxiv.org/abs/1511.04994

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