Aiming at the low mass transfer efficiency of conventional reactors dealing with highly viscous gas–liquid systems, this work proposes a novel capillary-embedded ultrasonic microreactor (CEUM) based on an ultrasonic field and microscale effect for enhancing the mass transfer performance. The results show that the formation of bubbles in the channel is the result of a combination of multiple forces. As the ultrasonic power increased, the flow pattern gradually shifted from a bubble flow to a Taylor bubble flow. In addition, ultrasound increases the bubble size, generation frequency, and gas flow rate, and this trend becomes more pronounced with increasing ultrasound power. Lastly, the periodic contraction–expansion phenomenon of the bubbles was observed and revealed a sinusoidal evolution of the bubble sizes, a phenomenon that significantly perturbs the flow field in the liquid phase, which, in turn, facilitates the gas–liquid mass transfer. This study is presented to provide a promising method of enhancement for dispersion and mass transfer in highly viscous gas–liquid systems.

中文翻译：

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研究毛细管嵌入超声微反应器中高粘度气液系统的分散特性


针对处理高粘度气液系统的常规反应器传质效率低的问题，本研究提出了一种基于超声场和微尺度效应的新型毛细管嵌入超声微反应器 （CEUM），以增强传质性能。结果表明，通道中气泡的形成是多种力共同作用的结果。随着超声波功率的增加，流型逐渐从气泡流转变为泰勒气泡流。此外，超声波会增加气泡大小、产生频率和气体流速，并且随着超声波功率的增加，这种趋势变得更加明显。最后，观察到气泡的周期性收缩-膨胀现象，并揭示了气泡大小的正弦演变，这种现象会显著扰动液相中的流场，从而促进气液传质。本研究旨在为高粘度气液系统中的分散和传质提供一种有前途的增强方法。