Hello. I'd like to calculate the integrated flux of a vector field through a patch on the boundary. For example, after solving say a Laplace equation for temperature, I'd take the gradient of the temperature, and integrate the normal component of that over some part of the boundary (a Physical Surface in 3-D or Physical Line in 2-D) over which I'd specified the temperature with a Dirichlet condition in order to get the heat transfer rate.
I read that Plugin(Integrate) `integrates...the circulation/flux of vector fields over line/surface elements', so that looks ideal, but I guess I'm not calling it correctly. For example (to avoid posting a lengthy data file) say I load the tutorial t7.geo, then use Plugin(Gradient) (on the `background mesh' view) to generate a vector field. If I save the `background mesh Gradient' view as a Gmsh msh, it's only got the triangular domain elements, not the linear boundary elements. If I save the mesh though (Ctrl-Shift S or File/Save Mesh) it does have the linear boundary elements. Anyway, when I apply Plugin(Integrate) to the background mesh Gradient and then save that as a Gmsh msh, it contains a single point element at the centre of the domain and the scalar value 0. 1. What does the scalar value 0 mean? 2. How do I get the integrated flux of a vector field through each Physical Line/Surface boundary patch in two/three dimensions? Thanks. _______________________________________________ gmsh mailing list [email protected] http://www.geuz.org/mailman/listinfo/gmsh
