Evaluation of Multilouvered-Fin-Based Heat Exchangers for Automobile Exhaust Energy Harvesting Systems

Abstract

Heat exchanger modules with thermoelectric generators are being used to harness energy from automobile exhaust flows. This paper focuses on increasing the hot-side heat transfer for improved performance of the thermoelectric generators using internal louvered fins. The flow and heat transfer behavior inside the exhaust-pipe test section are modeled using computational fluid dynamics. The multilouvered fins basically have multi-flat-plate behavior and enhance the heat transfer by deflecting the air from its original path and aligning it with the plane of the louvers. The heat transfer and pressure drop characteristics are compared with the baseline flow in a channel without louvered fins. Optimization of the louvered fin geometry is performed to determine the configuration that provides highest heat transfer while providing least pressure drop across the pipe length.