Self-assembly of bubble swarm in large cavities in step-type parallelized microchannels and its feedback on bubble formation

被引:0
作者
Zhang Z. [1 ]
Yin X. [1 ]
Zhu C. [1 ]
Ma Y. [1 ]
Fu T. [1 ]
机构
[1] State Key Laboratory of Chemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin
来源
Lixue Xuebao/Chinese Journal of Theoretical and Applied Mechanics | 2020年 / 52卷 / 02期
关键词
Bubble swarm; Lattice; Mesoscale; Microchannel; Self-assembly;
D O I
10.6052/0459-1879-19-251
中图分类号
学科分类号
摘要
Step-emulsification microfluidic devices attract attentions due to the ability for the high-throughput production of bubbles and droplets. In this study, the bubble behavior of the bubble swarm in the cavity in a step-type parallelized microchannel and its feedback effect on bubble formation were studied by using a high-speed camera. The operating variables were the position of gas/liquid phase inlet, gas flow rate and liquid flow rate. Two bubble generation modes were observed: single-tube generation mode and multi-tube generation mode. The variation trend of the complex behavior of bubble swarm in the cavity with operating conditions was studied. It is found that in the confined space, the bubble can be self-assembled into a two-dimensional lattice with geometric features in the horizontal plane: including an ordered row triangular lattice, an ordered vertical triangular lattice, and a disordered triangular lattice. As the gas pressure changes, the crystal lattice changes, the bubble surface area becomes larger, and the interfacial energy becomes larger. Then, the effects of complex behavior of bubble swarm on bubble generation were analyzed by using the concepts of mesoscale, energy and activation. These fully explain the mesoscale characteristics of bubble behavior in confined spaces. The determinants of the bubble self-assembly path are revealed. It is indicated that the self-assembly path of bubbles is determined by the size and distribution of bubbles. The coefficient of variation of CV is used to represent the crystal structure of bubbles, and the coefficient of variation for the ordered triangular lattice is less than 5%, while that for the disordered triangular lattice is greater than 5%. © 2020, Chinese Journal of Theoretical and Applied Mechanics Press. All right reserved.
引用
收藏
页码:420 / 430
页数:10
相关论文
共 41 条
[1]  
Fu T.T., Ma Y.G., Funfschilling D., Et al., Bubble formation and breakup mechanism in a microfluidic flow-focusing device, Chemical Engineering Science, 64, 10, pp. 2392-2400, (2009)
[2]  
Wang Z., Wu X., Chen K., Et al., A theoretical microfluidic flow model for the cell culture chamber under the pressure gradient and electric field driven loads, Chinese Journal of Theoretical and Applied Mechanics, 50, 1, pp. 124-137, (2018)
[3]  
Zhao Y.C., Chen G.W., Yuan Q., Liquid-liquid two-phase flow patterns in a rectangular microchannel, AICHE Journal, 52, 12, pp. 4052-4060, (2006)
[4]  
Han Y., Liu Z., Wang Y., Gas-liquid two-phase flowregimes and impact factors in T-junction microreactor, Chinese Journal of Theoretical and Applied Mechanics, 51, 2, pp. 441-449, (2019)
[5]  
Li G.H., Yuan X.G., Song W.Q., Gradient mesh approach for capturing characteristics of gas-liquid Taylor flow in microchannels, Chemcial Industry and Engineering, 33, 5, pp. 86-95, (2016)
[6]  
Gao T., Sun J., Fan Y., Et al., PIV experimental investigation on the behavior of particle in the turbulent boundary layer, Chinese Journal of Theoretical and Applied Mechanics, 51, 1, pp. 103-110, (2019)
[7]  
Yuan Q., Chen G.W., Yue J., Gas-liquid microreaction technology: recent developments and future challenges, Chinese Journal of Chemical Engineering, 16, 5, pp. 663-669, (2008)
[8]  
Groisman A., Enzelberger M., Quake S.R., Microfluidic memory and control devices, Science, 300, 5621, pp. 955-958, (2003)
[9]  
Huo Y., Wang J., Zuo Z., Et al., Electrohydrodynamic characteristics of liquid bridge formation at the dripping mode of electrosprays, Chinese Journal of Theoretical and Applied Mechanics, 51, 2, pp. 425-431, (2019)
[10]  
Jahnisch K., Hessel V., Lowe H., Et al., Chemistry in microstructured reactors, Angewandte Chemie International Edition, 43, pp. 406-446, (2004)