Mathematics
Fast solvers for high-order finite element discretizations of the de Rham complex
Vortrag im AG Numerik Seminar von Dr. Charles Parker, University of Oxford
When?
May 20, 2025, 15:30-16:30
Where?
Raum 314
Dolivostr. 15
64293 Darmstadt
Organiser
FB Mathematik, AG Numerik
Contact
Many applications in electromagnetism, magnetohydrodynamics, and pour media flow are well-posed in spaces from the 3D de Rham complex involving H1, H(curl), H(div), and L2. Discretizing these spaces with the usual conforming finite element spaces typically leads to discrete problems that are both structure-preserving and uniformly stable with respect to the mesh size and polynomial degree. Robust preconditioners/solvers usually require the inversion of subproblems or auxiliary problems on vertex, edge, or face patches of elements. For high-order discretizations, the cost of inverting these patch problems scales like O(p^9) and is thus prohibitively expensive. We propose a new set of basis functions for each of the spaces in the discrete de Rham complex that reduce the cost of the patch problems to O(p^6) complexity. By taking advantage of additional properties of the new basis, we propose further computationally cheaper variants of existing preconditioners. Various numerical examples demonstrate the performance of the solvers.
Tags
Mathematik, Numerik