Effect of transfer on liquid-liquid dispersion in microchannels

doi:10.11949/j.issn.0438-1157.20150651

Abstract

Abstract:

The flow and dispersion performance of water/octanol in coaxial annular microchannels was investigated. The transport of sulfur acid into water releasing heat was used to achieve liquid-liquid dispersion accompanied with mass and heat transfer. The effects of flow rate and sulfur acid concentration on the flow pattern and droplet size were investigated. The results show that the transport of sulfur acid can result in the formation of new O/W/O flow pattern and the change in flow pattern maps. It was also found that the droplet size decreased with the increase of the transport process. Based on the results, the dynamic interfacial tension of the falling off droplets was calculated and the effects of mass and heat transfer on the liquid-liquid dispersion were analyzed, respectively.

Key words: microchannels, transport, interfacial tension, liquid-liquid flow

摘要：

在同轴环管微通道中,采用水/正辛醇形成两相体系,利用硫酸向水中传质并释放热量以实现伴随传质传热的微分散过程,研究了两相流速、硫酸浓度对两相流型和液滴大小的影响规律。结果发现,传递会引发O/W/O新流型的产生和流型分布区域变化。探讨了传递强度对于分散液滴尺寸的影响,通过计算液滴脱落时的动态界面张力,分析了传质和传热对于液液微分散影响的大小。

关键词: 微通道, 传递, 界面张力, 液液两相流

CLC Number:

TQ025.5

ZHANG Jisong, LIU Guotao, WANG Kai, LUO Guangsheng. Effect of transfer on liquid-liquid dispersion in microchannels[J]. CIESC Journal, 2015, 66(8): 2940-2946.

张吉松, 刘国涛, 王凯, 骆广生. 微通道内传递对液液分散过程的影响规律[J]. 化工学报, 2015, 66(8): 2940-2946.

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