Modelling and characterization of thermal transfer in a thermoelectric generator based on catalytic combustion

The portable power needs are improving nowadays due to the large use of battery supplied devices. With this target a compact and lightweight thermoelectric generator (TEG) with the electrical output matching the common battery backup needs has been developed and characterized. The actual focus of the work is the study of the thermal transfer from the catalytic combustion to the thermoelectric modules used for the energy conversion. The target is to study how the hot side can drive the performances of the overall device through the management of heat flux and temperatures in order to achieve the maximum combustion efficiency and the compliance with the technological limits of chalcogenides materials. The study presents an experimental tests phase and a computational modelling phase, both leading to the definition of a new design for the hot side components. The design development has been enabled by the use of additive solution for the building of the new improved combustors. The new operating configuration to improve the performances at low mass flow rates has been thought. For the study of thermal coupling between combustor and modules, a local detailed analysis of combustor surfaces temperature profile using infrared images has been performed. Based on the data collected, a redesign of the hot side was carried out, with computational modelling of conductive and convective solutions of heat transfer enhancement. The resulting designs have been adapted to the technological limits of 3D building and produced for further developments.