Influence of geometric parameter and contact resistances on the thermal-electric behavior of a segmented TEG

Thermoelectric (TE) generation technology plays an increasingly significant role in a global environment. A desirable approach to improve the efficiency of thermoelectric generator (TEG) is to segment the nand/or p-leg into several parts with different materials for increasing the average thermoelectric figure of merit of the legs, and to operate with a relatively larger temperature gradient. In this study, a threedimensional model is developed for the performance analysis of a segmented TEG, and the geometric design optimization of the TEG is examined numerically with the use of the temperature-dependent thermoelectric materials. Specifically, the temperature, heat flow, electric potential, electric current and Joule heating in the thermoelectric modules are investigated in detail. Also, the efficiency and effectiveness of the TEG is analyzed with the design variables such as the ratio of cross-sectional area of p-leg and n-leg, the length ratio of different materials in the segmented leg, and the geometry configurations of p- and n-legs. Furthermore, the effect of the contact resistance on the TEG performance is considered. The results show that a proper design of the geometric parameters can lead to an optimal design of thermoelectric generation systems with higher efficiency. (c) 2022 Elsevier Ltd. All rights reserved.

Automated summary

Thermoelectric generation technology has a significant role globally. The efficiency of a thermoelectric generator (TEG) can be improved by segmenting the n and/or p-leg into several parts with different materials and operating with a larger temperature gradient. This study develops a three-dimensional model to analyze the performance of a segmented TEG and numerically examines the geometric design optimization, considering temperature-dependent thermoelectric materials. The study investigates various parameters including temperature, heat flow, electric potential, electric current, Joule heating, and contact resistance to analyze the efficiency and effectiveness of the TEG.