Semi-Analytical and Experimental Investigation of the Magnetic Field Generated by a Permanent Magnet

For magnetic field calculations, cylindrical permanent magnets are often approximated as ideal, azimuthally symmetric solenoids. Despite the frequent usage of this approximation, research papers demonstrating the validity and limitations of this approach are scarcely available. In this paper, the experimentally derived magnetic field of a cylindrical permanent magnet is compared with the semi-analytically calculated magnetic field of an ideal solenoid. An experimental setup for measuring the magnetic field distribution is demonstrated and employed for gathering the data. The proposed setup allows to measure the distributions of the axial and radial components of the magnetic field surrounding the magnet. In addition, we calculated the magnetic field using the FEM method and compared it with the solution of an ideal solenoid and discussed the obtained deviation.