Operating Temperature Range of Magnetic Refrigerator with Mn-based Magnetic Material

Abstract

A room-temperature magnetic refrigerator is attractive that does not use HCFC or its alternatives. It is expected that a wide temperature range can be get by packing multiple magnetic materials in active magnetic refrigerator (AMR) ducts. We focus on a temperature span that is difference between temperature of hot end and cold end when manganese-based magnetic materials are used. These materials have a large entropy change per unit volume, while the temperature range in which to show a large effect is relatively small. In order to investigate the temperature span, temperature distribution of inside AMR duct was measured. Experimental results show that larger temperature span can be obtained for the case of using multiple magnetic materials than that of using a single material. It is confirmed that when the large temperature span is obtained, the temperature distribution in the AMR duct corresponds to the temperature range in which the respective materials show a large magnetic entropy change.