Modeling magnetization using Whitney facet elements

An integral method for computation of static magnetic fields exploits Whitney facet elements for approximation of magnetization of arbitrary solids or thin shells. A co-tree gauge of unknown variables allows constructing an exactly divergence-free magnetization inside homogeneous media. The approach leads to positive definite and symmetric matrices of algebraic equations. Comparisons of the method with gradient representation of magnetization, and also with usual piecewise constant approximation show some advantages, which are attributed to proper approximation of the operator null-space