Heat transfer optimization of a fully solid state micro-unit regeneration magnetic refrigerator

Abstract

This paper introduced and numerically investigated a fully solid state magnetic refrigerator based on a micro-unit regeneration cycle and Peltier elements, in which Peltier elements were used to enhance heat transfer and heat regeneration. Due to the limitation of heat transfer rate under solid state, topology optimization was used to improve the heat transfer structure of the magnetic refrigerator. The heat transfer behaviors of the three heat transfer configurations were tested and compared experimentally: Gd-only, parallel sheets and topology optimization structure. The cycle performance before/after optimization and without/with Peltier elements was then carefully compared and discussed using a validated simulation model. The results showed that the performance of the fully solid state magnetic refrigerator was greatly improved after heat transfer optimization. The improvement was more significant when operating with Peltier elements. The heat transfer optimization approaches, results and conclusions can serve as guidelines for solid state MR design and optimization.