Cylindrical Permanent Magnet B Fields Cylindrical permanent magnet fields can be modeled by placing scalar potentials, +/-Vm0, on the cylinder ends, which here is the top and bottom of the black mass at the center of the contour pattern. The fields are then found by first solving the LaPlace equation div(Vm)=0 everywhere. Then B=grad(Vm) and this gives the correct B field everywhere except inside the magnet. It is necessary to integrate numerically over the effective sources at the top and bottom of the magnet. Because the top and bottom outer edges of the magnet are sharp, the field near these edges is very large and variable. Everywhere else, the fields shown are quite accurate.
Click here Graphics Description Magnet Length Axial B Field Radial B Field Magnitude of B Field