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arXiv · 2012.12557

Lattice Boltzmann simulations of stochastic thin film dewetting

Stefan Zitz·Andrea Scagliarini·Jens Harting
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Abstract

We study numerically the effect of thermal fluctuations and of variable fluid-substrate interactions on the spontaneous dewetting of thin liquid films. To this aim, we use a recently developed lattice Boltzmann method for thin liquid film flows, equipped with a properly devised stochastic term. While it is known that thermal fluctuations yield shorter rupture times, we show that this is a general feature of hydrophilic substrates, irrespective of the contact angle. The ratio between deterministic and stochastic rupture times, though, decreases with $\theta$. Finally, we discuss the case of fluctuating thin film dewetting on chemically patterned substrates and its dependence on the form of the wettability gradients.

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Stefan Zitz, Andrea Scagliarini, Jens Harting. 2020-12-23. Lattice Boltzmann simulations of stochastic thin film dewetting. https://doi.org/10.1103/physreve.104.034801

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