Simulation of heat transfer enhancement effects in microreactors

Sate-of-the-art microstructuring techniques allow to model the interface for heat and mass transfer in miniaturized reactions systems on a micrometer scale. In this context, two different approaches for heat transfer enhancement are presented. The ideas put forward rely on entrance flow effects and inertial flows in meandering channels, respectively. It is found that a heat transfer enhancement of at least one order of magnitude can be achieved compared to unstructured channels. On this basis, a miniaturized heat-exchanger reaction system is investigated, where a kinetic model of an endothermic, heterogeneously catalyzed gas-phase reaction is used. The miniaturized heat-exchanger reactor, both with and without heat transfer enhancement, is subsequently benchmarked against conventional fixed bed technology. It is shown that, for the reaction system under study, a substantial reduction of the required amount of catalyst can be achieved in microsystems.