{ "id": "1805.07835", "version": "v1", "published": "2018-05-20T22:51:08.000Z", "updated": "2018-05-20T22:51:08.000Z", "title": "An ultraweak formulation of the Kirchhoff-Love plate bending model and DPG approximation", "authors": [ "Thomas Führer", "Norbert Heuer", "Antti H. Niemi" ], "comment": "Accepted for publication in Mathematics of Computation", "categories": [ "math.NA" ], "abstract": "We develop and analyze an ultraweak variational formulation for a variant of the Kirchhoff-Love plate bending model. Based on this formulation, we introduce a discretization of the discontinuous Petrov-Galerkin type with optimal test functions (DPG). We prove well-posedness of the ultraweak formulation and quasi-optimal convergence of the DPG scheme. The variational formulation and its analysis require tools that control traces and jumps in $H^2$ (standard Sobolev space of scalar functions) and $H(\\mathrm{div\\,Div})$ (symmetric tensor functions with $L_2$-components whose twice iterated divergence is in $L_2$), and their dualities. These tools are developed in two and three spatial dimensions. One specific result concerns localized traces in a dense subspace of $H(\\mathrm{div\\,Div})$. They are essential to construct basis functions for an approximation of $H(\\mathrm{div\\,Div})$. To illustrate the theory we construct basis functions of the lowest order and perform numerical experiments for a smooth and a singular model solution. They confirm the expected convergence behavior of the DPG method both for uniform and adaptively refined meshes.", "revisions": [ { "version": "v1", "updated": "2018-05-20T22:51:08.000Z" } ], "analyses": { "subjects": [ "74S05", "74K20", "35J35", "65N30", "35J67" ], "keywords": [ "kirchhoff-love plate bending model", "ultraweak formulation", "dpg approximation", "construct basis functions", "variational formulation" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }