5 papers
Uniformly Bounded Cochain Extensions and Uniform Poincaré Inequalities
Erik Nilsson, Silvano Pitassi
In this paper, we construct a novel global bounded cochain extension operator for differential forms on Lipschitz domains. Building upon the classical universal extension of Hiptma…
Divergence-free unfitted finite element discretisations for the Darcy problem
Santiago Badia, Anne Boschman, Alberto F. Martín +3
We develop an unfitted compatible finite element discretisation for the Darcy problem based on -conforming flux spaces and discontinuous pressure spaces. The metho…
Ghost stabilisation for cut finite element exterior calculus
Daniele Di Pietro, Jérôme Droniou, Erik Nilsson
We introduce the cut finite element method in the language of finite element exterior calculus, by formulating a stabilisation -- for any form degree -- that makes the method robus…
Stabilized Lagrange Multipliers for Dirichlet Boundary Conditions in Divergence Preserving Unfitted Methods
Thomas Frachon, Erik Nilsson, Sara Zahedi
We extend the divergence preserving cut finite element method presented in [T. Frachon, P. Hansbo, E. Nilsson, S. Zahedi, SIAM J. Sci. Comput., 46 (2024)] for the Darcy interface p…
Nodal auxiliary space preconditioners for mixed virtual element methods
Wietse Boon, Erik Nilsson
We propose nodal auxiliary space preconditioners for facet and edge virtual elements of lowest order by deriving discrete regular decompositions on polytopal grids and generalizing…