OP-II-3

OP-I-10SINGLE-PHASE FLUID FLOW DISTRIBUTION AND HEATTRANSFER IN MICROSTRUCTURED REACTORSEvgeny V. Rebrov and Jaap C. SchoutenDepartment of Chemical Engineering and Chemistry,Eindhoven University of Technology,P.O. Box 513, 5600 MB Eindhoven, The Netherlands,e.rebrov@tue.nlSingle-phase microreactors and micro heat-exchangers are widely used inindustrial and scientific applications. Over the course of the past two decades, manyconflicting publications with the results on the validity of classical macroscaleequations for microchannel fluid flow and heat transfer have been given.In several cases, operation of microreactors has shown that their expectedefficiency can not be reached due to either a non-uniform distribution of reactantsbetween different channels, or due to a flow maldistribution between individualmicroreactors working in parallel. The latter can result in substantial temperaturedeviations between different microreactors resulting in thermal runaway which couldarise from an exothermic reaction. Thus advances in the understanding of heattransfer and fluid flow distribution continue to be crucial in achieving improvedperformance, efficiency and safety in microstructured reactors applied for differentapplications. The experimental and numerical results on fluid flow distribution, heattransfer and combination thereof will be presented. Heat transfer in microchannelscan be suitably described by standard theory and correlations, but scaling effects(entrance effects, conjugate heat transfer, viscous heating, temperature dependentproperties) have often to be accounted for in microsystems. Experiments with singlechannels are generally in good agreement with predictions from publishedcorrelations. The accuracy of multichannel experiments is lower due to flowmaldistribution. A set of design recommendations for purposes of improving reactorperformance will be provided.56