Application of simulations to thermodynamic properties of materials for magnetic refrigeration

Abstract

A magnetic refrigeration system is a complex system that involves the magnetocaloric effect (MCE) and the heat transfer problems working in a coupled manner. For this purpose, characterization of materials showing MCE is needed. Calorimetric characterization allows the obtention of thermodynamic variables needed for a precise quantification of this effect. More specifically, in systems with continuous magnetic field variation, in order to calculate the heat generation due to MCE, the knowledge of their magnetocaloric parameters—adiabatic temperature change ΔST and isothermal entropy change ΔTS—and the heat capacity C, for every temperature and magnetic field present is needed. In this work, La(Fe1-x-yCoxSiy)13 family materials have been either characterized or interpolated and used in numerical simulations in COMSOL Multiphysics™ software. The characterization was carried out with measurements of ΔTS, ΔST and C and the calculation of other derived parameters, at different temperatures and magnetic fields.