Enhancement thermoelectric generators output power from heat recovery of chimneys by using flaps

Abstract

This study proposes a new and effective way to improve waste heat recovery from chimneys using thermoelectric generators cooled by natural convection heat sinks. A modified heat sink equipped with a flap fixed at the top of its base is used instead of only the conventional heat sink. A three-dimensional model is presented and solved by using ANSYS Fluent and ANSYS Mechanical for the complete setup. The model simulates completely the heat transfer phenomenon surrounding the first three heat sinks as part of a column of thermoelectric generator modules covering a vertical chimney wall. Also, it simulates the thermal-electric phenomenon inside the thermoelectric generator to predict the thermoelectric generators output power at different operating conditions. The impact of flap's dimensions and material (conductive and non-conductive) on the thermoelectric generator performance is studied. The flap's depth varies from 14 to 50 mm and height from 20 to 35 mm. This modified heat sink achieves about 64% increase in the thermoelectric generators cooling rate, yielding an increase in their output power by 129%. Results prove that sing the proposed modified heat sink in cooling thermoelectric generators (passively) maintains the system simplicity with no running cost and performs more than double its performance.