Single-phase fluid flow distribution and heat transfer in microstructured reactors
Single-phase fluid flow distribution and heat transfer in microstructured reactors
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DOI：
10.1016/j.ces.2010.05.044
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发表时间：
2011-04
影响因子：
4.7
通讯作者：
E. Rebrov;J. J. Schouten-J.;M. Croon
中科院分区：
文献类型：
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作者：
E. Rebrov;J. J. Schouten-J.;M. Croon
近十年来，单相微反应器和微型热交换器在工业和科学领域得到了广泛的应用。在一些情况下，微反应器的运行表明，由于不同通道之间的反应物分布不均匀或单个微反应器之间并联工作的流量分布不均匀，无法达到预期的效率。后一个问题可能导致不同微反应器之间的温度偏差，从而导致放热反应引起的热失控。因此，对传热和流体流动分布的理解的进步对于实现用于不同应用的微结构反应器的性能，效率和安全性的改进至关重要。本文综述了公开文献中关于流体流动分布、传热及其组合的实验和数值结果。微通道中的传热可以用标准理论和相关性来适当地描述，但在微系统中，通常要考虑尺度效应（入口效应、共轭传热、粘性加热和温度依赖特性）。单通道的实验与已发表的相关性的预测很好地吻合。由于水流的不均匀分布，导致多通道实验精度降低。本文着重从理论和实验两方面研究了流动不均匀对催化微反应器热反应和转化反应的影响。审查最后提出了一套旨在改善反应堆性能的设计建议。
Single-phase microreactors and micro-heat-exchangers have been widely used in industrial and scientific applications over the last decade. In several cases, operation of microreactors has shown that their expected efficiency cannot be reached either due to non-uniform distribution of reactants between different channels or due to flow maldistribution between individual microreactors working in parallel. The latter problem can result in substantial temperature deviations between different microreactors resulting in thermal runaway which could arise from an exothermic reaction. Thus advances in the understanding of heat transfer and fluid flow distribution continue to be crucial in achieving improved performance, efficiency and safety in microstructured reactors used for different applications. This paper presents a review of the experimental and numerical results on fluid flow distribution, heat transfer and combination thereof, available in the open literature. Heat transfer in microchannels can be suitably described by standard theory and correlations, but scaling effects (entrance effects, conjugate heat transfer, viscous heating, and temperature-dependent properties) have often to be accounted for in microsystems. Experiments with single channels are in good agreement with predictions from the published correlations. The accuracy of multichannel experiments is lower due to flow maldistribution. Special attention is devoted to theoretical and experimental studies on the effect of a flow maldistribution on the thermal and conversion response of catalytic microreactors. The review concludes with a set of design recommendations aimed at improving the reactor performance.