Effects of Performance and Normalized Parameters on Various Materials Based Multistage Thermoelectric Generator

Multi-staging and variable cross section greatly improve the performance of thermoelectric generators. Hence, the present theoretical study analyzes a multi-stage-variable-shaped thermoelectric generator (MVS-TEG) for a combination of dissimilar materials. Effects on voltage, power, conversion efficiency, normalized constraints (voltage, power, and conversion efficiency), and second law efficiency with a row number, exhaust inlet temperature, and the coolant flowrate have been investigated. Results reveal that the row number is the most critical input parameter followed by exhaust inlet temperature and coolant flowrate. Also, the work gives optimum values of rows for voltage and power as Nx = 19 for MVS TEG-1, MVS TEG-3, and MVS TEG-4 while Nx = 18 for MVS TEG-2. The exhaust inlet temperature variation increases the voltage and power output by 54-59% and by 53-58% respectively. The coolant flow variation has a greater impact on the conversion efficiency and the average improvement in the efficiency is about 9.23% in the present study. The second law efficiency decreases with the increase in all the input parameters.