Hello, I would like to solve the following equation (which does not directly come from a PDE):
\int dV f(x) * \partial_r g(x) = \int dA u(x) * \partial_n g(x) f(x) is known, u(x) is unknown, and the equation should hold for any g(x) that satisfy Laplace's equation. In other words, I'm looking for a weight function u(x), such that the surface integral of the normal derivative of any g(x) (weighted by u) gives the same result as the volume integral of the radial derivative of g(x) (weighted by the known function f(x)). Is it possible to do this with FEniCS? It seems that the equation itself is easy to express in UFL, but I am not sure how do deal with the fact that there are no boundary conditions, and that any trial function g(x) needs to satisfy Laplace's equation. Best, Nikolaus -- Nikolaus Rath, Ph.D. Senior Scientist Tri Alpha Energy, Inc. +1 949 830 2117 ext 211 _______________________________________________ fenics mailing list [email protected] http://fenicsproject.org/mailman/listinfo/fenics
