Development and experimental analysis of a multi-bed active magnetic regenerator

Room temperature magnetic refrigeration technology is a potentially efficient and environmentally friendly refrigeration technology. A magnetic refrigeration prototype with two high/low magnetic field regions was designed and built. The device consists of eight beds, using gadolinium particles as the magnetocaloric material, with a total filling mass of 1.35 kg. The hydraulic system consists mainly of a magnetic centrifugal pump, solenoid valves, and check valves. The flow of the heat transfer fluid through the regenerators is controlled by controlling the opening and closing of the solenoid valves. The no-load temperature span, cooling capacity, power consumption, and COP of the regenerators were investigated separately. The maximum no-load temperature span of 17.5 K was obtained at an AMR frequency of 0.5 Hz and flow rate of 1.15 L/min. The total power consumption and the magnetic power and pumping power were analyzed for different operating conditions.