分离-重组式微反应器内气液流动与传质的耦合及强化机理研究

分离-重组式新型微反应器结合分流和混沌对流两种典型强化方式，已在混合和传质过程强化中展现出巨大优势，但其对气液传质的强化与调控机制至今尚未充分阐明。本项目拟采用高速摄像仪、显微粒子图像测速仪（micro-PIV）和显微激光诱导荧光光谱检测仪（micro-LIF），并结合流体体积（VOF）数值模拟方法，研究不同构型分离-重组式微反应器内的气液两相流动与传质特性。揭示气泡运动、形变、破裂和聚并过程中界面及其周围液相流场和浓度场的动态演变规律，阐明气泡行为、流场、浓度场和传质间的耦合机理以及气液传质内在机制，明确分离-重组式微反应器内汇聚-发散微通道和障碍物对气液传质的协同强化与调控机制。在此基础上，匹配液相停留时间与传质性能，并基于系统能量的最优化利用，提出分离-重组式微反应器的优化方案，为分离-重组式微反应器的创新设计和工业应用提供理论基础。

The novel split-and-recombination microreactors have shown great potential in enhancing the mixing and mass transfer by combining the advantages of lamination and chaotic convection. However, to date, the detailed mechanisms of enhancement and regulation of gas-liquid mass transfer in the split-and-recombination microreactor remain mostly unexplored. In this project, the gas-liquid two-phase flow and mass transfer characteristics in the split-and-recombination microreactor will be investigated experimentally (by high-speed camera, micro-particle image velocimetry (micro-PIV), and micro-laser-induced fluorescence spectroscopy (micro-LIF)) and numerically (by computational fluid dynamics (VOF method)) to reveal the enhancing mechanism of the gas-liquid mass transfer. To elaborate the coupling mechanisms among bubble behavior, liquid flow field, concentration field and mass transfer, the time-resolved movement, deformation, breakup and coalescence of bubbles will be revealed as well as the surrounding liquid flow field and concentration field. In particular, the synergism and regulation mechanism of the convergent-divergent microchannel and obstacle for gas-liquid mass transfer will be clarified. Finally, based on the optimal correlation among residence time, mass transfer performance and energy consumption, the optimization method will be proposed for the design and industrial application of advanced split-and-recombination microreactors.