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arXiv · 1904.12358

Universality in coalescence of polymeric fluid drops

Sarath Chandra Varma·Siddhartha Mukherjee·Aniruddha Saha·Aditya Bandopadhyay·Aloke Kumar·Suman Chakraborty
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Abstract

Coalescence of liquid droplets involves an interplay between capillary forces, viscous forces and inertial forces. Here, we unveil a universal temporal evolution of the neck radius during the coalescence of two polymeric drops. Through high speed imaging we demonstrate that drops of polyacrylamide (PAM), poly-vinyl alcohol (PVA), polyethylene oxide (PEO), polyethylene glycol (PEG) and xanthan gum (XG) depict a universal behavior $R/\sqrt(\nu_0\lambda) \sim (t/\lambda)^{0.36}(C/C^{*})^{-0.83}$ over a dilute, semi-dilute and non-dilute range of concentrations. A linear Phan-Thein-Tanner viscoelastic model captures the temporal aspect of universality.

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Sarath Chandra Varma, Siddhartha Mukherjee, Aniruddha Saha, Aditya Bandopadhyay, Aloke Kumar, Suman Chakraborty. 2019-04-28. Universality in coalescence of polymeric fluid drops. https://doi.org/10.1039/d0sm01663b

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