Performance analysis and optimization of an annular thermoelectric generator integrated with vapor chambers

To overcome the structural barriers of conventional annular thermoelectric generators (ATEGs), a new ATEG integrated with vapor chambers (VCs) is proposed in this paper, where the use of VCs enables a large hot-end contact area and a high temperature uniformity for traditional planar thermoelectric modules. Besides, a numerical model for the ATEG is built to conduct performance analysis and optimization under different parameters. Results suggest that the heat absorption of the ATEG increases with the increase of the number of VCs, thereby boosting the output power of the system. When the flow rate is lower than 35 g/s, the optimal number of VCs for the ATEG is 12, with the highest output power, conversion efficiency, net power, and net efficiency of 287.3 W, 5.36 %, 214.1 W, and 3.99 %, respectively, at the exhaust temperature of 800 K. Besides, the exhaust temperature does not affect the optimal result, while the ATEG should be designed with fewer VCs when applied to the waste heat recovery with a larger flow rate. The increase in the VC thermal conductivity is not related to heat absorption but can improve temperature uniformity, and the thermal conductivity of 4000 W m−1 K−1 already meets performance requirements. This study provides new perspectives on the structure design of ATEGs.