Power generation characteristics of a thermoelectric modules-based power generator assisted by fishbone-shaped fins: Part II – Effects of cooling water parameters

Operation control combined with the optimization of the structure for thermoelectric generators (TEGs) based on thermoelectric modules (TEMs) is an effective method to improve the power generation characteristics of TEGs. The present study is intended to experimentally investigate the power generation characteristics including voltage and power output, and conversion efficiency of a TEM-based TEG, which is added fishbone-fins aiming to enhance heat exchange of hot inlet air to the hot side of TEG. The effects of mass flow rate (MFR) of cooling water on the power generation characteristics of TEGs are analyzed in the case of the hot inlet air temperatures of 200–500°C and a constant MFR of hot inlet air. Compared to TEM-based TEG without fishbone-shaped fins, TEM-based TEG with fishbone-shaped fins has a maximum increase by 31.37 V of voltage output and 16.49 W of power output. Conversion efficiency of TEM-based TEG with fishbone-shaped fins is determined through the temperatures of hot side and cold side as well as figure-of-merit (ZT). As a result, an average increase of 2.93% of the conversion efficiency for TEM-based TEG with fishbone-shaped fins compared to the case of TEM without fishbone-shaped fins is found. In addition, the outlet temperature of cooling water is also practically measured to evaluate the influences of fishbone-shaped fins on the heat flux transferred from hot side to cold side of TEM.