Experimental investigation of a three-material layered active magnetic regenerator

This work reports on experimental studies using an active magnetic regenerative test apparatus (AMRTA) in near room-temperature refrigeration cycles. Experiments using regenerator beds composed of three different magnetocaloric materials combined in a layered configuration with applied fields of 2 T have produced no-load temperature spans in excess of 50 K. The test apparatus uses two active magnetic regenerators each containing approximately 135 g of refrigerant. An overview of the test apparatus, operating parameters, and performance is described. The impacts of operation at varying heat rejection temperatures, applied fields of 1.5 T and frequencies between 0.65 and 1.0 Hz are presented. In addition, the impacts of operating pressure and applied load on temperature spans are discussed.