A multiscale modeling of Thermoelectric Generators for conversion efficiency optimization

An attractive option for constructing Thermoelectric Generators (TEGs) is to incorporate a water-fed heat exchanger with commercially available thermoelectric modules. A major design concern to such an implementation is the heat exchanger geometry. In this study, a thorough performance evaluation of TEGs embedded in 30 configurations is conducted through simulations to optimize thermoelectric systems for maximum power output. The cross-sectional area of a single channel is decreased gradually, while total pressure drop across the flows is maintained constant. It is found that for the configurations analyzed, the conversion efficiencies are significantly improved by implementing the water-fed heat exchanger at the micro-scale. In addition, effects of variation of channel length for the initially-studied thermoelectric schemes are studied. It is shown that a reduction of channel length may result in promoted power generation. Finally, a theoretical analysis of inlet temperature is performed to provide practical guidelines for designing TEGs in a conversion capability sense.