Towards modeling thermoelectric properties of anisotropic polycrystalline materials

We report on the development of a finite element method based computational framework for evaluating thermoelectric properties of polycrystalline nanostructured materials and composites at mesoscale. This effort was advanced by formulation, testing and (if possible) validation of thermoelectric 'benchmark problems,' that progressed from simple to more advanced cases. The following benchmark problems were investigated: (a) effective Seebeck effect in a thermocouple, (b) Peltier heating and cooling at a single interface between two materials with different Seebeck coefficients, (c) coupled heat and electrical current transport through an anisotropic polycrystalline material. Excellent agreement with prior experimental or computational results was observed for the cases (a) and (b). The developed framework establishes the capabilities necessary to elucidate the workings of thermoelectric effects at the mesoscale level and could provide new opportunities for improvement of operational efficiency of nanoengineered thermoelectric materials and composites.(c) 2022 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.