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arXiv · 2107.07978

Nodal auxiliary space preconditioning for the surface de Rham complex

Yuwen Li
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Abstract

This work develops optimal preconditioners for the discrete H(curl) and H(div) problems on two-dimensional surfaces by nodal auxiliary space preconditioning [R. Hiptmair, J. Xu: SIAM J. Numer. Anal. \textbf{45}, 2483-2509 (2007)]. In particular, on unstructured triangulated surfaces, we develop fast and user-friendly preconditioners for the edge and face element discretizations of curl-curl and grad-div problems based on inverting several discrete surface Laplacians. The proposed preconditioners lead to efficient iterative methods for computing harmonic tangential vector fields on discrete surfaces. Numerical experiments on two- and three-dimensional hypersurfaces are presented to test the performance of those surface preconditioners.

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Yuwen Li. 2021-07-16. Nodal auxiliary space preconditioning for the surface de Rham complex. https://doi.org/10.1007/s10208-023-09611-0

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