Finite Element Method Magnetics (FEMM) is an open source finite element analysis software package for solving electromagnetic problems. The program addresses 2D planar and 3D axisymmetric linear and nonlinear harmonic low frequency magnetic and magnetostatic problems and linear electrostatic problems. It is a simple, accurate, and low computational cost freeware product, popular in science and engineering.
For better understanding, please see following N38SH distribution of magnetic field lines.
