On the flexibility of agglomeration based physical space discontinuous Galerkin discretizations

JOURNAL OF COMPUTATIONAL PHYSICS

卷:231

Article

Bassi, F.¹  Botti, L.^1,2  Colombo, A.¹  Di Pietro, D. A.³  Tesini, P.⁴ 

[1] Univ Bergamo, Dipartimento Ingn Ind, I-24044 Dalmine, BG, Italy

[2] Mario Negri Inst Pharmacol Res, Dept Biomed Engn, Ranica, BG, Italy

[3] IFP Energies Nouvelles, F-92500 Rueil Malmaison, France

[4] SKF Engn & Res Ctr, Modelling & Simulat Dept, SE-41550 Gothenburg, Sweden

关键词: Diffusion equation;    Laplacian discretization;    Discontinuous Galerkin methods;    Polyhedral elements;    Orthonormal hierarchical basis functions;    Reduced numerical integration;    Meshfree;    h-Adaptivity;   

DOI  :  10.1016/j.jcp.2011.08.018

来源: Elsevier

【 摘 要 】

In this work we show that the flexibility of the discontinuous Galerkin (dG) discretization can be fruitfully exploited to implement numerical solution strategies based on the use of elements with very general shapes. Thanks to the freedom in defining the mesh topology, we propose a new h-adaptive technique based on agglomeration coarsening of a fine mesh. The possibility to enhance the error distribution over the computational domain is investigated on a Poisson problem with the goal of obtaining a mesh independent discretization. The main building block of our dG method consists of defining discrete polynomial spaces directly on physical frame elements. For this purpose we orthonormalize with respect to the L-2-product a set of monomials relocated in a specific element frame and we introduce an easy way to reduce the cost related to numerical integration on agglomerated meshes. To complete the dG formulation for second order problems, two extensions of the BR2 scheme to arbitrary polyhedral grids, including an estimate of the stabilization parameter ensuring the coercivity property, are here proposed. (C) 2011 Elsevier Inc. All rights reserved.

【 授权许可】

Free