On Oct 20, 2009, at 1:09 AM, weasky wrote:
My project is to add two cylinders together (one small one attached with one big one),
I'm going to assume you're talking about FiPy's CylindricalGrid classes, and not actual cylindrical meshes. If you're generating actual cylinders, then just use your meshing tool to generate the whole thing. I'm also going to assume that the attachment is axial, as the junction between two pipes at right angles is quite complicated and will definitely require using a dedicated meshing tool.
is it possible to do this and is it possible to use a non-uniform girds for the big one and in the same time be able to merge the two meshes?
They must have faces in common, which can be difficult to achieve with non-uniform grids. More importantly, the result of concatenating two 2D meshes (cylindrical or otherwise) is a generic Mesh2D. It knows nothing about the geometry adjustments that CylindricalGrid's need to do. So, in short, no, I don't think FiPy can do this.
You may be able to achieve what you want by defining a single, large diameter cylinder, and then mask out or reset the values that would be outside the narrow cylinder.
All, in all, I think you may be better off using Gmsh to create the mesh you want.
