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arXiv · 1408.5374

Discontinuous Petrov-Galerkin boundary elements

Norbert Heuer·Michael Karkulik
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Abstract

Generalizing the framework of an ultra-weak formulation for a hypersingular integral equation on closed polygons in [N. Heuer, F. Pinochet, arXiv 1309.1697 (to appear in SIAM J. Numer. Anal.)], we study the case of a hypersingular integral equation on open and closed polyhedral surfaces. We develop a general ultra-weak setting in fractional-order Sobolev spaces and prove its well-posedness and equivalence with the traditional formulation. Based on the ultra-weak formulation, we establish a discontinuous Petrov-Galerkin method with optimal test functions and prove its quasi-optimal convergence in related Sobolev norms. For closed surfaces, this general result implies quasi-optimal convergence in the L^2-norm. Some numerical experiments confirm expected convergence rates.

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Norbert Heuer, Michael Karkulik. 2014-08-22. Discontinuous Petrov-Galerkin boundary elements. https://arxiv.org/abs/1408.5374

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