An experimental investigation of exhaust waste heat recycling by thermoelectric generators under different thermal conditions for internal combustion engines

Abstract

Almost 70% of heat power produced by pistons in internal combustion engines is lost due to exhaust and cooling. In the course of the heating process, 25% of useful energy transfers to the exit shaft. There have been a lot of studies on recycling waste heat of internal combustion engines, especially on cooling and exhaust systems. A thermoelectric generator is an important way to recycle waste energy in exhaust systems of internal combustion engines. In this study, an air-cooled thermoelectric generator was designed to recycle waste heat energy in exhaust systems of internal combustion engines and its performance was tested. Waste heat recycling tests were conducted by measuring voltage, current, and power values under different thermal conditions depending on the change in load resistance. The results obtained were compared with the results of analyses and experiments. Maximum voltage value at RI = 45Ω load resistance was obtained as 11.03 V (experiment) and 11.22 V (analysis), and maximum current value at RI = 5Ω load resistance as 0.42 A (experiment) at Th = 250°C, Δ T = 40°C.