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arXiv · 2012.08213

Economically High-Order Unstructured-Grid Methods: Clarification and Efficient FSR Schemes

Hiroaki Nishikawa
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Abstract

In this paper, we clarify reconstruction-based discretization schemes for unstructured grids and discuss their economically high-order versions, which can achieve high-order accuracy under certain conditions at little extra cost. The clarification leads to one of the most economical approaches: the flux-and-solution-reconstruction (FSR) approach, where highly economical schemes can be constructed based on an extended kappa-scheme combined with economical flux reconstruction formulas, achieving up to fifth-order accuracy (sixth-order with zero dissipation) when a grid is regular. Various economical FSR schemes are presented and their formal orders of accuracy are verified by numerical experiments.

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Hiroaki Nishikawa. 2021-08-11. Economically High-Order Unstructured-Grid Methods: Clarification and Efficient FSR Schemes. https://doi.org/10.1002/fld.5028

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