Performance analysis of compact thermoelectric generation device for harvesting waste heat

In order to save energy and to effectively utilize the waste heat from diesel engines, a compact thermoelectric power generation (TEG) device with two heat collectors and three water coolers was designed. A three-dimensional steady-state fluid-solid coupling simulation was carried out for the structure formed by the heat collector-thermoelectric modules (TEMs)-water coolers of the device. The heat transfer characteristics, temperature and flow fields of the heat collector-TEMs-water coolers were analyzed. The output voltage and power of the device were experimentally investigated on a TEG test bench. The results show that the average temperature difference on both sides of each layer of TEMs ranges from 43 to 48 K. The temperature differences in the upper TEMs are slightly greater than those in the lower TEMs. There is small difference among the heat transfer coefficients of each TEM module with an average of about 82.6 W/(m(2).K). The device generates the maximum output power of 15.8 W with a 560 K inlet air temperature and a hot air volume flow of 171 L/min. It is shown that more studies are required to perform cooperative the optimization of multiphysics simulation and comprehensive evaluation of heat transfer and power generation performance.