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  • 17m1147044

    Final published version, 1 MB, PDF-document

DOI

We develop the general form of the variational multiscale method in a discontinuous Galerkin framework. Our method is based on the decomposition of the true solution into discontinuous coarse-scale and discontinuous fine-scale parts. The obtained coarse-scale weak formulation includes two types of fine-scale contributions. The first type corresponds to a fine-scale volumetric term, which we formulate in terms of a residual-based model that also takes into account fine-scale effects at element interfaces. The second type consists of independent fine-scale terms at element interfaces, which we formulate in terms of a new fine-scale "interface model." We demonstrate for the one-dimensional Poisson problem that existing discontinuous Galerkin formulations, such as the interior penalty method, can be rederived by choosing particular fine-scale interface models. The multiscale formulation thus opens the door for a new perspective on discontinuous Galerkin methods and their numerical properties. This is demonstrated for the one-dimensional advection-diffusion problem, where we show that upwind numerical fluxes can be interpreted as an ad hoc remedy for missing volumetric fine-scale terms.
Original languageEnglish
Pages (from-to)1333-1364
Number of pages32
JournalMultiscale Modeling and Simulation
Volume16
Issue number3
DOIs
Publication statusPublished - 1 Jan 2018

    Research areas

  • Multiscale discontinuous Galerkin methods, Residual-based multiscale modeling, Upwinding, Variational multiscale method

ID: 47063169