The Performance of Rotary Magnetic Refrigerators with Layered Beds of LaFeSiH

Abstract

Astronautics Corporation has designed, constructed, and extensively tested two generations of magnetic refrigerators employing a rotary magnet-fixed bed architecture. This paper reviews and summarizes the performance of these prototypes. In particular, the testing on the 1st-generation prototype demonstrates the significant performance advantage associated with the use of layered beds of LaFeSiH, a magnetocaloric material with a sharp, first-order transition and a readily adjustable Curie temperature. The 2nd-generation prototype exhibits peak performance of 2.4 kW of cooling power over a temperature span of 11 °C, corresponding to 168 W of specific exergetic cooling power. We believe that this is the highest performance yet reported for a magnetic refrigeration system. Moreover, the system performance is in good agreement with theoretical prediction.

Experimental characterization of active magnetic regenerators constructed using laser beam melting technique

“…A porous solid refrigerant, made of magnetocaloric material (MCM), is used instead. It is exposed to a change of magnetic field, which is usually created by a permanent magnet [5,6,[11][12][13]. During this (de)magnetization process, MCM (absorbs) releases the heat (from) to the ambient via a heat transfer liquid.…”