Acta Mechanica Sinica

, Volume 34, Issue 4, pp 632–643 | Cite as

Study of droplet flow in a T-shape microchannel with bottom wall fluctuation

  • Yan Pang
  • Xiang Wang
  • Zhaomiao LiuEmail author
Research Paper


Droplet generation in a T-shape microchannel, with a main channel width of 50 \(\upmu \hbox {m}\), side channel width of 25 \(\upmu \hbox {m}\), and height of 50 \(\upmu \hbox {m}\), is simulated to study the effects of the forced fluctuation of the bottom wall. The periodic fluctuations of the bottom wall are applied on the near junction part of the main channel in the T-shape microchannel. Effects of bottom wall’s shape, fluctuation periods, and amplitudes on the droplet generation are covered in the research of this protocol. In the simulation, the average size is affected a little by the fluctuations, but significantly by the fixed shape of the deformed bottom wall, while the droplet size range is expanded by the fluctuations under most of the conditions. Droplet sizes are distributed in a periodic pattern with small amplitude along the relative time when the fluctuation is forced on the bottom wall near the T-junction, while the droplet emerging frequency is not varied by the fluctuation. The droplet velocity is varied by the bottom wall motion, especially under the shorter period and the larger amplitude. When the fluctuation period is similar to the droplet emerging period, the droplet size is as stable as the non-fluctuation case after a development stage at the beginning of flow, while the droplet velocity is varied by the moving wall with the scope up to 80% of the average velocity under the conditions of this investigation.


Droplet length Droplet generation Forced fluctuation Droplet velocity 



The authors are grateful for the support of the National Natural Science Foundation of China (11572013 and 11702007) and the China Postdoctoral Science Foundation (2017M610725).


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Copyright information

© The Chinese Society of Theoretical and Applied Mechanics; Institute of Mechanics, Chinese Academy of Sciences and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.College of Mechanical Engineering and Applied Electronics TechnologyBeijing University of TechnologyBeijingChina

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