To create wedge mesh you should create a 3D mesh in a first place.
For example , you can use BlockMesh or create brick mesh using external mesher.
After that you create extrudeMesh utility using extrudeMeshDict:
/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 5.x |
| \\ / A nd | Web: www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class dictionary;
object extrudeMeshDict;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
// What to extrude:
// patch : from patch of another case ('sourceCase')
// mesh : as above but with original case included
// surface : from externally read surface
//constructFrom mesh;
constructFrom patch;
// If construct from patch/mesh:
sourceCase ".";
sourcePatches (back);
// If construct from patch: patch to use for back (can be same as sourcePatch)
exposedPatchName front;
// Flip surface normals before usage. Valid only for extrude from surface or
// patch.
flipNormals false;
//- Wedge extrusion. If nLayers is 1 assumes symmetry around plane.
extrudeModel wedge;
nLayers 1;
expansionRatio 0.001;
sectorCoeffs
{
axisPt (0 0 0);
axis (0 0 -1);
angle 5; // For nLayers=1 assume symmetry so angle/2 on each side
}
// Do front and back need to be merged? Usually only makes sense for 360
// degree wedges.
mergeFaces false; //true;
// Merge small edges. Fraction of bounding box.
mergeTol 1e-13;
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
Example could be downloaded here: extrude archive.