Special Heat Transfer Mechanisms: Active and Passive Thermal Diodes - Magnetocaloric Energy Conversion: From Theory to Applications - page 253

Fig. 6.31 Four phases of operation in the perpendicular direction to the fl uid fl ow of the

magnetocaloric device with active thermal diodes

6.6.2 Cascade Magnetocaloric Device with Thermal Diodes

A cascade magnetocaloric device with thermal diodes comprises a number of
single-stage devices stacked on each other, as shown in Fig. 6.32 . The purpose of
such a design is to increase the operating temperature span of the whole device.
From Fig. 6.33 it is clear that each MC material operates in a single-stage mode at
different temperature levels. However, the heat from the MC material at lower
temperature is transported via a thermal diode to the MC material at higher tem-
perature. In this manner the heat is transported from the cold heat exchanger to the
hot heat exchanger.