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arXiv · 1806.01931

Order Preserving Interpolation for Summation-by-Parts Operators at Non-Conforming Grid Interfaces

Martin Almquist·Siyang Wang·Jonatan Werpers
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Abstract

We study non-conforming grid interfaces for summation-by-parts finite difference methods applied to partial differential equations with second derivatives in space. To maintain energy stability, previous efforts have been forced to accept a reduction of the global convergence rate by one order, due to large truncation errors at the non-conforming interface. We avoid the order reduction by generalizing the interface treatment and introducing order preserving interpolation operators. We prove that, given two diagonal-norm summation-by-parts schemes, order preserving interpolation operators with the necessary properties are guaranteed to exist, regardless of the grid-point distributions along the interface. The new methods retain the stability and global accuracy properties of the underlying schemes for conforming interfaces.

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Martin Almquist, Siyang Wang, Jonatan Werpers. 2018-06-05. Order Preserving Interpolation for Summation-by-Parts Operators at Non-Conforming Grid Interfaces. https://doi.org/10.1137/18m1191609

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