FEM2D_POISSON_CG_BAFFLE
A Poisson Problem in a Region with Baffles

FEM2D_POISSON_CG_BAFFLE is a FORTRAN90 library which defines the geometry and other data for the "baffle" problem, a rectangular region with 13 hexagonal baffles. The problem is suitable for solution by fem2d_poisson_cg.

The region is a rectangle with lower left corner (0.0,1.0) and upper right corner (12.0,7.0). The mesh was created using MESH2D, with a maximum element size of 0.5. The mesh comprises 512 nodes and 874 elements.

Licensing:

The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.

Languages:

FEM2D_POISSON_CG_BAFFLE is available in a C++ version and a FORTRAN90 version and a MATLAB version.

Related Data and Programs:

FEM2D_POISSON_CG, a FORTRAN90 program which solves Poisson's equation on a triangulated region, using the finite element method, sparse storage, and a conjugate gradient solver.

FEM2D_POISSON_CG_ELL, a FORTRAN90 library which defines the geometry of an L-shaped region, as well as boundary conditions for a given Poisson problem, and is called by fem2d_poisson_cg as part of a solution procedure.

FEM2D_POISSON_CG_LAKE, a FORTRAN90 library which defines the geometry of a lake-shaped region, as well as boundary conditions for a given Poisson problem, and is called by fem2d_poisson_cg as part of a solution procedure.

Source Code:

• baffle.f90, the user-supplied routines to evaluate the right hand side, linear coefficient, and boundary conditions;
• baffle_nodes.txt, a text file containing a list, for each node, of its X and Y coordinates;
• baffle_nodes.png, a PNG image of the nodes;
• baffle_elements.txt, a text file containing a list, for each element, of the three nodes that compose it;
• baffle_elements.png, a PNG image of the element mesh;

Examples and Tests:

• baffle.txt, the output file;
• baffle_values.txt, a text file containing the solution U at each node (X,Y);

You can go up one level to the FORTRAN90 source code page.