Analysis of Functionally Graded Material Thermoelectric Generators with Variable Material Properties Using the Differential Transform Method

A differential transform method (DTM) is developed to investigate thermoelectric generators composed of functionally graded materials (FGM) with varying material properties. FGM thermoelectric generators with linear, parabolic, and exponential material property variations are studied. The semi-analytical solutions of the temperature field of FGM thermoelectric devices are obtained by DTM. In order to validate the proposed method, the temperature field, heat flux distribution, and energy conversion efficiency of the FGM thermoelectric devices obtained by DTM are compared with numerical solutions. The calculated results agree well with those obtained by numerical solutions. The results show that the functionally graded parameters of FGM have a notable influence on the temperature field, heat flux distribution, and energy conversion efficiency of the thermoelectric devices. In addition, the FGM thermoelectric devices with linear and exponential variations in material properties have better performance than those with parabolic material property variations. These results provide a theoretical basis for the performance optimization of FGM thermoelectric devices.