Jamming modulates coalescence dynamics of shear-thickening colloidal droplets
Abstract
Recent investigations into coalescence dynamics of complex fluid droplets revealed the existence of sub-Newtonian behaviour for polymeric fluids (elastic and shear thinning). We hypothesize that such delayed coalescence or sub-Newtonian coalescence dynamics may be extended to the general class of shear thickening fluids. To investigate this droplets of aqueous corn-starch suspensions were chosen and its coalescence in sessile pendant configuration was probed by high-speed real time imaging. Temporal evolution of the neck (growth) during coalescence was quantified as a function of suspended particle weight fraction \phi_w. The necking behaviour was found to evolve as the power-law relation where R is neck radius with exponent implying it is a subset of the generic sub-Newtonian coalescence. Second significant delay in the coalescence dynamics is observed for particle fractions beyond the jamming fraction {\ \phi}_w>\ \phi_J\geq0.35}. Our proposed theoretical model captures this delay implicitly through altered suspension viscosity stemming from increased particle content.
Keywords
Cite
@article{arxiv.2310.18707,
title = {Jamming modulates coalescence dynamics of shear-thickening colloidal droplets},
author = {M. V. R. Sudheer and Sarath Chandra Varma and Aloke Kumar and Udita U. Ghosh},
journal= {arXiv preprint arXiv:2310.18707},
year = {2023}
}