The boundary-element-like estimation of the electromagnetic force in the finite element method

The authors propose the following method. Firstly, they analyze the investigated region only by the finite element method (FEM), after that they locate the hypothetical boundary properly surrounding the points where they desire the values of the magnetic flux density B in the homogeneous region. Finally, they calculate B at inner points by the boundary element method (BEM) using the values obtained by the FEM as the boundary conditions. This method is easily applied to complicated multi-material problems. Calculating B at inner points continuously by the BEM, seems to result in an improvement of the accuracy of the estimation of the electromagnetic force compared with the results obtained only by the FEM. They adopt several physical quantities to this method as unknowns, and also show the propriety and advantage of this method by analyzing a simple model