Title: A comparison of some mesh adaptation schemes with FreeFem++
Speaker: Prof. Frederic Hecht, Lab. Jacques-Louis Lions, University Paris VI France
Date/Time: September 15, 2005, 11:00-12:00 noon (MT)
Location: Building 980, Room 95 (Sandia-NM), Building 915, Room S101 (SNL-CA)
Brief 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 element: 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.
- Available 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.
CSRI POC: Philippe P. Pebay, (925) 294-0224 |