Abstract
This paper discusses pressure variation on a wall during the process of liquid flow and droplet formation in a T-junction microchannel. Relevant pressure in the channel, deformation of the elastic wall, and responses of the droplet generation are analyzed using a numerical method. The pressure difference between the continuous and dispersed phases can indicate the droplet-generation period. The pressure along the channel of the droplet flow is affected by the position of droplets, droplet-generation period, and droplet escape from the outlet. The varying pressures along the channel cause a nonuniform deformation of the wall when they are elastic. The deformation is a vibration and has the same period as the droplet generation arising from the process of droplet formation.
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Acknowledgments
The project was supported by the National Natural Science Foundation of China (Grants 11072011 and 11572013), as well as the Doctoral Fund of Innovation of the Beijing University of Technology. We thank members of the Complex Fluids Group at Princeton University, especially Prof. Howard Stone and Dr. Hyoungsoo Kim, for many fruitful discussions and comments during the experiments conducted for this study.
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Pang, Y., Liu, Z. & Zhao, F. Downstream pressure and elastic wall reflection of droplet flow in a T-junction microchannel. Acta Mech. Sin. 32, 579–587 (2016). https://doi.org/10.1007/s10409-016-0561-7
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DOI: https://doi.org/10.1007/s10409-016-0561-7