Events & Teaching

Upcoming Events

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July 25 – 29, 2016 (ZIB-SEM)
Workshop/Konferenz: Patterns of Dynamics
more ... Location
Zuse-Zentrum für Informationstechnik (ZIB), Takustr. 7, 14195 Berlin, Seminarraum

Host
Freie Universität Berlin
Technische Universität Berlin
WIAS Berlin
SFB 910 ``Control of self-organizing nonlinear systems: Theoretical methods and concepts of application''
Humboldt-Universität zu Berlin
Thursday, 04.08.2016, 14.00 Uhr (WIAS-ESH)
Seminar Numerische Mathematik
P. Lederer, TU Wien, Österreich:
An exact divergence-free reconstruction operator for the Taylor--Hood element
more ... Location
Weierstraß-Institut, Mohrenstr. 39, 10117 Berlin, Erdgeschoss, Erhard-Schmidt-Hörsaal

Abstract
In this talk we focus on a well-known issue of discretization techniques for the incompressible (Navier) Stokes equations. The numerical solution is only discrete divergencefree, which may have a major impact on quantitative and qualitative properties of the solution. In recent years Alexander Linke and cooperators developed a methodology to reconstruct exactly divergence-free solutions from discrete divergence-free ones, and use this operator within the Navier Stokes solver. In this work we extend this approach from discontinuous pressure elements to continuous pressure elements including the popular Taylor-Hood element. While for discontinuous pressures the reconstruction operator is given by element-wise local procedures, we have to extend the construction to vertex or element patches. The reconstruction leads to non conforming methods, where the consistency error is estimated in dual norms. Convergence of optimal order is proven (see [1]). The method is implemented in NGS-Py which is based on the nite element library Netgen/NGSolve. Several examples are presented.
References
[1] P. Lederer. Pressure Robust Discretizations for Navier Stokes Equations: Divergence-free Reconstruction for Taylor-Hood Elements and High Order Hybrid Discontinuous Galerkin Methods. Master's thesis, TU Wien, Austria, 2016.

Host
WIAS Berlin
August 12 – 15, 2016 (WIAS-ESH)
Workshop/Konferenz: 5th Annual ERC Berlin-Oxford Young Researchers Meeting on Applied Stochastic Analysis
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Weierstraß-Institut, Mohrenstr. 39, 10117 Berlin, Erdgeschoss, Erhard-Schmidt-Hörsaal

Host
European Research Council
WIAS Berlin
September 8 – 9, 2016 (WIAS-ESH)
Workshop/Konferenz: 1st Leibniz MMS Mini Workshop on CFD & GFD
more ... Location
Weierstraß-Institut, Mohrenstr. 39, 10117 Berlin, Erdgeschoss, Erhard-Schmidt-Hörsaal

Host
WIAS Berlin