Heat sink fin optimization on thermoelectric generator surfaces to improve thermoelectric power generation

Abstract This study develops a novel thermoelectric generator system to utilize vehicle exhaust gas waste heat and convert it into electrical energy. A three-dimensional thermoelectric generator system with innovative heat sinks on both the hot and cold sides is designed to boost the thermoelectric generator’s output power and conversion efficiency. Three novel heat sink models for both sides of the thermoelectric generator are generated according to the square-pin fin size and the gaps between the fins to investigate the effects of the exhaust gas temperature and its flow rate. According to the findings, the highest temperature difference between both sides of the thermoelectric generator and the highest hot side heat transfer rate are obtained as 185.56 K and 113.69 W for Model C, and the maximum output power reached up to 4.44 W with a conversion efficiency of 3.90 % for the same model. As a result, the net output power is maximized with Model C at 4.07 W concerning the pressure drop and the pumping power. Considering waste heat recovery systems, Model C yields an increase in thermoelectric power generation by 23.3 % from 3.6 W to 4.44 W compared to the systems in the literature.