Thermoelectric–magnetocaloric energy conversion.

The research and development of the magnetocaloric technology is facing several problems and limits, which represent a serious obstacle toward the industrialization. One of the largest obstacles is the operation at low frequencies and, consequently, low power densities of existing prototype devices. Introduction of new heat transfer mechanisms represent a potential solution. One of those is to introduce thermal diodes. The article deals with heat transfer analyses of hybrid magnetocaloric devices, based on solid-state thermal diodes with embodied thin plate magnetocaloric materials. For the purpose of the study, thin film Peltier elements were considered as thermal diodes. These can provide very fast heat transport from, or to the magnetocaloric material. The article presents a new, quasi 2-dimensional numerical model. The model serves for dynamic heat transfer simulations of magnetocaloric devices, which apply thermal diodes. With the small adaptation of the program, one is able to provide simulations for different types of thermal diodes. In this article, the results of numerical analyses are shown for different operating characteristics. Important guidelines for the further exploration of this promising idea are discussed.