Title
Divergence-free Reconstruction Operators for Pressure-Robust Stokes Discretizations with Continuous Pressure Finite Elements.
Abstract
Classical inf-sup stable mixed finite elements for the incompressible (Navier-)Stokes equations are not pressure-robust, i.e., their velocity errors depend on the continuous pressure. However, a modification only in the right-hand side of a Stokes discretization is able to reestablish pressure-robustness, as shown recently for several inf-sup stable Stokes elements with discontinuous discrete pressures. In this contribution, this idea is extended to low and high order Taylor-Hood and mini elements, which have continuous discrete pressures. For the modification of the right-hand side a velocity reconstruction operator is constructed that maps discretely divergence-free test functions to exactly divergence-free ones. The reconstruction is based on local H (div)-conforming flux equilibration on vertex patches, and fulfills certain orthogonality properties to provide consistency and optimal a priori error estimates. Numerical examples for the incompressible Stokes and Navier-Stokes equations con firm that the new pressure-robust Taylor-Hood and mini elements converge with optimal order and outperform significantly the classical versions of those elements when the continuous pressure is comparably large.
Year
DOI
Venue
2017
10.1137/16M1089964
SIAM JOURNAL ON NUMERICAL ANALYSIS
Keywords
Field
DocType
incompressible Navier-Stokes equations,mixed finite elements,pressure-robustness,exact divergence-free velocity reconstruction,flux equilibration
Compressibility,Discretization,Mathematical optimization,Stokes' law,Vertex (geometry),Mathematical analysis,Orthogonality,Finite element method,Operator (computer programming),Stokes stream function,Mathematics
Journal
Volume
Issue
ISSN
55
3
0036-1429
Citations 
PageRank 
References 
9
0.56
11
Authors
4
Name
Order
Citations
PageRank
Philip L. Lederer1131.71
Alexander Linke29212.29
Christian Merdon3627.33
Joachim Schöberl421321.63