Thermal Design of Thermoelectric Generators for Automobile Waste Heat Recovery

In this present work, we attempt to maximize the electrical power generation by optimizing Thermoelectric Generator (TEG) geometry for a prescribed TEG volume. A plate-fin heat exchanger topology is assumed and consideration is given to additional pressure drops associated with the fins placed in the exhaust flow path; and the cross-sectional changes across TEG inlet-exit ports. The thermal profile in the TEG is computed such that different thermoelectric modules may be placed where they provide the maximum Seebeck coefficient and hence provide the maximum power output. Multiple filled skutterudites are employed in the higher temperature regions and Bismuth Telluride modules are used at lower temperature regions of the TEG. Separate calculations are performed for cases where the available maximum number of TEMs is limited for cost optimization.