A natural-gas-fired thermoelectric generation (TEG) system is an efficient way for simultaneously providing heat and electric power, and it can be used as a movable power system for field trips and a heatpower coordinated supply for residential homes. In this paper, a high-temperature and medium-temperature coupled TEG system driven by direct combustion heat source is proposed, and a new burner with baffle is designed to enhance the heat transfer between fired gas and the hot side of TEG. The optimal geometrical dimensions of the new burner are obtained by conducting a 2D model in ANSYS, which including combustion reactions, flow, and heat transfer in simplified TEGs. Comparative experiment results show that the inner-wall temperature of high-temperature TEG module averagely increases by 73K, and the power generation and conversion efficiency of the TEG system are improved by 42.48% and 3.38%, respectively. In order to further improve the performance of hightemperature TEG, the 2D model is developed by using an equivalent thermoelectric effects model of segmented high-temperature TEG, and its accuracy is verified by the experimental results. The influences of thermo-element length and number on TEG performance are revealed, and further improvement method, i.e. adding fins in the cold water jacket is proposed and verified.
Keywords High-temperature and medium-temperature coupled TEG system; Burner; Geometric and cold side optimization