, Volume 49, Issue 6, pp 1457–1467 | Cite as

Investigation the effects of shear rate on stationary droplets coalescence by lattice Boltzmann

  • Ehsan Amiri Rad


Coalescence is the process by which two or more droplets merge to form a single droplet. It can take place in many processes, ranging from meteorology to astrophysics. When two stationary droplets are suspended in a bulk vapor, if the gap between the droplets has been smaller than a critical value, the two droplets will coalesce. In this paper, single component, two phase flow is modeled under shear flow using a free energy lattice Boltzmann approach and the coalescence of stationary droplets are investigated for different cases of radius and shear rate. The results show that there is a critical gap between droplets and for the values larger than that they will not coalesce. Also in the case of constant thermophysical properties, this critical gap is a function of droplet radius and shear rate.


Droplet coalescence Shear flow Lattice boltzmann Free energy 



I wish to express my sincere gratitude to Professor Luca. Biferalle and Dr. Mauro Sbaragaglia of university of Rome. “Tor vergata” because of good discussions.


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Copyright information

© The Author(s) 2014

Authors and Affiliations

  1. 1.Hakim Sabzevari UniversitySabzevarIran

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