Power generation characteristics of a thermoelectric modules-based power generator assisted by fishbone-shaped fins: Part I – effects of hot inlet gas parameters

Several researchers and manufacturers are paying attention to technologies of waste heat recovery due to its effectiveness in the conversion of the energy from exhaust gas into electric power. Therefore, the analysis of the effects of thermoelectric generator (TEG) design on the power generation characteristics is an essential issue to develop its applications to waste heat recovery technologies aiming at pollution environment reduction and improvement of efficiency for energy use. In this study, a TEG based on the thermoelectric module (TEM) with fishbone-shaped fins was built for experimental purposes. The comparison of power generation characteristics including voltage and power output, conversion efficiency, and pressure drop for the fabricated TEM-based TEG with fishbone-shaped fins and TEM-based TEG without fins under conditions of the hot inlet gas temperatures from 200-500°C along with the changes in mass flow rate of hot inlet gas was conducted. The results indicated that TEM with fishbone-shaped fins had a maximum increase by 30.7 V of voltage output, 17.54 W of power output, 3.68% of conversion efficiency compared to the case of TEM without fishbone-shaped fins. However, the average pressure drop for TEM with fishbone-shaped fins was 3.65 Pa higher than that of TEM without fishbone-shaped fins. The experimental study showed that TEM-based TEG system had achieved high conversion efficiency by attaching the fishbone-shaped fins to the surface of the hot side in the TEG structure.