On the Magnetic Forces in Magnetic Cooling Machines: Numerical Calculations and Experimental Investigations

In this paper, we present a detailed study of the magnetic interaction forces encountered in magnetic cooling machines between magnetocaloric (MC) refrigerants and a magnetic field source. Numerical calculations have been performed using different magnetocaloric materials. The obtained results have been analyzed and compared with experimental measurements. In order to reduce the magnetic forces in reciprocating magnetic cooling systems and as a consequence increase their thermodynamic performances, a special configuration of the MC refrigerants is proposed. Numerical investigations have been carried out to analyze the resulting magnetic force. The obtained results are confirmed by measuring directly the involved forces on our recent developed magnetic refrigerator. The preliminary calculations demonstrate that more than 90% of the energy absorbed by the cooling machine can be saved with the new design, and consequently, a high coefficient of performance can be obtained.