Abstract
We studied the coalescence of two stationary equal-sized droplets in static vapor using a lattice Boltzmann approach. The non-ideal behavior of one-component, two-phase flow is coupled with BGK lattice Boltzmann by defining a suitable free energy function, which produces the correct equilibrium conditions of the flow. The accuracy of developed model is confirmed by calculating droplet surface tension for different conditions and comparing that with theoretical results. Finally, the coalescence process of two equal-sized drops is modeled and effective parameters on critical gap of coalescence are investigated. The results show that for two at-rest and equal-sized drops in a static flow, the critical gap of coalescence only depends on thickness of the interface, and other parameters such as droplet radius, density ratio and surface tension do not have influences on that directly.
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Ehsan Amiri Rad he is an assistant professor of Mechanical engineering at Hakim Sabzevari University. He received the B.Sc. in Mechanical Engineering from Iran University of Science and Technology in 2005 and M.Sc. in Energy Conversion from Ferdowsi University of Mashhad-Iran in 2007. His Ph.D. is from Ferdowsi University of Mashhad-Iran in 2011.
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Rad, E.A. Coalescence of two at-rest equal-sized drops in static vapor of the same material: A lattice Boltzmann approach. J Mech Sci Technol 28, 3597–3603 (2014). https://doi.org/10.1007/s12206-014-0821-z
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DOI: https://doi.org/10.1007/s12206-014-0821-z