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Title |
A comparison of some mesh adaptation schemes with FreeFem++
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| Speaker |
Frederic Hecht
Lab. Jacques-Louis Lions
Department of Civil & Environmental Engineering
University Paris VI, France
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| Date |
September 15, 2005 |
| Time |
10-11am (PT)
11am-noon (MT)
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| Location |
915/S101 (CA)
980/95 (NM)
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| Abstract |
FreeFem++ is a free software for the solution of 2D PDEs with the
finite element methods, that has been developed at the J-L Lions
Laboratory.
The main characteristics of FreeFem++ are:
- A large variety of available finite elements : linear and quadratic Lagrangian elements, discontinuous P1 and Raviart-Thomas elements, elements of a non-scalar type, mini-element, etc....
- Automatic interpolation of data on different meshes to an overmesh, storage of the interpolation matrix.
- Linear problems description (real or complex) thanks to a formal variational form, with access to the vectors and the matrix if needed.
- Includes tools to define discontinuous Galerkin formulations . Analytic description of boundaries. When two boundaries intersect, the user must specify the intersection points.
- Automatic mesh generator, based on the Delaunay-Voronoi method.
- Inner points density is proportional to the density of points on the boundary [cf. P-L George, "Meshing", Hermes 2000].
- Metric-based anisotropic mesh adaptation. The metric can be computed automatically from the Hessien of a solution.
- Every variable is typed.
- Avaliable solvers : LU, Cholesky, Crout, CG, GMRES, UMFPACK linear solver, eigenvalue and eigenvector computation.
- Online graphics, C++-like syntax.
- Many examples: Navier-Stokes, elasticity, Fluid structure, Schwarz's domain decomposition method, Eigen value problem, residual error indicator, etc.
- Parallel version using MPI
This presentation will use FreeFEM++ to compare the following scheme combined with mesh adaptation:
- Hessian mesh adaptation,
- residual error indicator,
- hierarchical error indicator.
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About the Speaker |
Dr. Hecht is a full professor at Paris-6 University (Jacques-Louis Lions Laboratory).
He received hid PhD in Applied Mathematics in 1980, and his Habilitation in Applied Mathematics in 1992, both from Paris-6 University.
Prior to his appointment with the Jacques-Louis Lions Laboratory, Dr. Hecht served on senior research staff of INRIA-Rocquencourt (France) through 1999.
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| Host |
Philippe P. Pebay, pppebay@sandia.gov, 925-294-2024
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This seminar series is hosted by the Computational Sciences and
Mathematics Research Department at Sandia National Labs in
Livermore, CA.
This seminar is funded by the Computer Science Research
Institute (CSRI).
To schedule a time to meet with the speaker before or after the talk,
please make arrangements with the host listed above.
Visitors from outside Sandia require at least 3 days notice in order
to attend. For more information, see http://csmr.ca.sandia.gov/csri/visitor.html.
The exception is any U.S. Citizens with a valid DOE badge. In this
case, call for "key service" using the phone at the turnstile in front
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valid for a period of one year).
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