Experimental and numerical analysis of the influence of the heat exchanger shape on the performance of a TEG module

Combustion processes involve a by-product in the form of waste heat. In many cases this energy is unused. Thermoelectric generators (TEGs) enable the capture and reuse of excess heat from existing combustion processes for other purposes. By utilising the Seebeck phenomenon, they allow heat energy to be converted directly into electrical energy. Researchers around the world are working to improve the performance of TEG modules by searching for new, more environmentally friendly thermoelectric materials. The use of a heat exchanger to increase the heat exchange surface area is a second way of improving the performance of the modules by increasing the temperature difference between the hot and cold sides. This enables the efficiency of these modules to be enhanced. In the automotive industry, TEGs are can be used to recover the heat of exhaust gases to supply electricity to several on-board GPS and MEMS sensors. In this study, which is part of the European InComEss project, the COMSOL Multiphysics software was used to analyse the effect of the heat exchanger shape on the performance of a TEG module. The simulation results were compared with measurements performed in the laboratory.