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arXiv · 1901.02264

Symmetry-preserving finite-difference discretizations of arbitrary order on structured curvilinear staggered grids

B. van 't Hof·M. J. Vuik
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Abstract

Symmetry-preserving (mimetic) discretization aims to preserve certain properties of a continuous differential operator in its discrete counterpart. For these discretizations, stability and (discrete) conservation of mass, momentum and energy are proven in the same way as for the original continuous model. This paper presents a new finite-difference symmetry-preserving space discretization. Boundary conditions and time integration are not addressed. The novelty is that it combines arbitrary order of convergence, orthogonal and non-orthogonal structured curvilinear staggered meshes, and the applicability to a wide variety of continuous operators, involving chain rules and nonlinear advection, as illustrated by the shallow-water equations. Experiments show exact conservation and convergence corresponding to expected order.

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B. van 't Hof, M. J. Vuik. 2019-01-08. Symmetry-preserving finite-difference discretizations of arbitrary order on structured curvilinear staggered grids. https://doi.org/10.1016/j.jocs.2019.06.005

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