Finite Element Simulation on Thermoelectric Performance of Tilted Mg₂Si/Ni Multilayer Composites

抄録

Mg₂Si is a promising n-type thermoelectric (TE) material for TE power generation using waste heat with temperature range of 300 to 600°C. Construction of multilayer composites with Mg₂Si and metallic material brings anisotropy in TE properties and enhancement in mechanical properties. The transverse TE force is created by giving vertical temperature difference in the tilted anisotropic TE material (transverse TE effect). In this study, the tilted Mg₂Si/Ni multilayer composites were focused on, and the influences of the structural conditions on the TE performance were investigated using a finite element simulation (FES). The simulations were carried out using two types of element models of the multilayer composites with different thickness ratio and tilt angle of Mg₂Si layer under the same temperature conditions of 500°C (hot side) and 100°C (cold side). The output power of the multilayer composites as a TE performance was calculated from the open-circuit voltage and the internal resistance estimated using FES. The values changed with the thickness ratio and the tilt angle. The optimum structural conditions of thickness ratio and the tilt angle which maximized the output power of the tilted multilayer composites were found out.