Toward an Experimental Design Approach for Magnetocaloric Refrigeration Systems

The magnetocaloric effect (MCE) is a magneto-thermodynamic phenomenon that heats and cools specific alloys through exposure to an alternating magnetic field. This phenomenon has the potential to create a temperature difference in a heat carrier mimicking a conventional vapor compression refrigeration cycle without harmful chemical byproducts. This research investigates the design of an experimental testing mechanism for identifying key interactions between design variables, while maximize temperature differential Key noise parameters (KNP). Fluid flow rate, magnetic field exposure time, and variations in heat exchanger configuration are explored. Understanding the significant interactions between these variables will lead to the design of a functional prototype that serves as a basis for future development in applications of the MCE for large-scale cooling systems. In this work, elemental gadolinium is used due to its high magnetic entropy change, and consequently high reversible temperature change when exposed to a magnetic field. An aqueous propylene glycol solution serves as the heat carrier based on its high heat capacity and basic pH level, reducing the possibility of degradation within the magnetocaloric material. The magnetic field is supplied by a grade N52 magnet with a magnetic field strength of approximately 0.9 Tesla. Based on this analysis, a concept stage design for experimentally maximizing the impact of the magnetocaloric effect is presented.