Net thermoelectric generator power output using inner channel geometries with alternating flow impeding panels

Abstract

Due to an abundance of low cost waste-heat in the industrial and residential sector, many studies in recent years have focused on applications of low grade heat for local energy needs. These include heat reutilization, thermal conversion to mechanical energy and thermal conversion to electricity. The thermoelectric effect presents a promising potential for effective conversion of low grade waste-heat yet is currently limited in application due to a conversion efficiency that is not cost effective. The present work focuses on mechanical methods to improve the thermal tension driving the electromotive force responsible for thermoelectric power production. More specifically, flow impeding geometries are inserted into the flow channels of a liquid-to-liquid thermoelectric generator thereby enhancing the heat transfer near its embedded thermoelectric modules. Consequentially, the thermal dipole across the modules is increased improving the overall power output. Care is taken to measure the adverse pressure drop caused by the use of the flow impeding geometries in order to evaluate the net power output. This net thermoelectric power output is measured, reported and discussed for a fixed inlet temperature difference, a fixed electrical load, varying flow rates and varying insert geometries.