Response surface based experimental analysis and thermal resistance model of a thermoelectric power generation system

In this work, a response surface analysis is carried out on an experimental setup of a combined two-phase flow thermosyphon and thermoelectric generator (TEG) system. Three-level Box-Behnken response surface method is adopted for the design of experiments, and analysis of variance is carried out to gauge the contribution of operating parameters on various performance parameters. Effects of operating parameters such as working pressure, filling ratio, evaporator length, and evaporator temperature are studied. The performance of the system itself is gauged concerning the maximum power obtained, open circuit voltage and short circuit current. With an increase in vacuum pressure and evaporator temperature, performance parameters are found to increase. However, performance parameters under the influence of filling ratio and evaporator length first decrease and then increase due to uneven variation in evaporation rate of working fluid. Experiments also reveal that the performance of the thermosyphon-assisted TEG system is mainly governed by pressure and evaporator temperature, whereas filling ratio and evaporator length have relatively lesser influence.