Design and assembling of a magnetic circuit for a thermomagnetic motor apparatus

Abstract

A thermomagnetic motor operates due to magnetization variation of magnetic materials around their transition or Curie temperature. The main components of these motors are the magnetic material (MM) and the magnetic circuit (MC). If the MM presents the transition temperature around room temperature, it may have potential to be used in thermomagnetic motors. Based on the current state-of-the-art, several first- and second-order transition magnetic materials with Curie temperature of 20 °C and above are known, and some of them present high magnetocaloric effect. The MC is responsible to guarantee a high magnetic field region which magnetically interacts with the MM. This way, the main objective of the present paper is the design and assembly of a double-C permanent magnet magnetic circuit, as part of a novel thermomagnetic motor design. Several 2D and 3D simulations were performed using COMSOL Multiphysics V5.3, which is a finite element analysis software for multiphysics simulation. Based on the simulation results, the MC was designed and built. After the construction, simulation results for magnetic field intensity and profiles along the transversal and axial directions were compared with experimental measurements, and a good agreement was verified.