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arXiv · 2603.23100

A numerical study on the coefficient of restitution of wet collisions

Abhishek Kumar Singh·Christopher Robert Kit Windows-Yule·Prapanch Nair
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Abstract

Using smoothed particle hydrodynamics (SPH) simulations, we investigate the coefficient of restitution (COR) in wet collisions and identify a scaling law governing its behavior. The simulations employ an updated-Lagrangian, mesh-free framework that is validated against experimental measurements. We neglect surface tension effects since the impact conditions correspond to a moderate-to-high Weber number regime. The COR is found to depend on the Stokes number and a dimensionless film thickness defined as the ratio of the liquid film thickness to the diameter of the impacting solid bead. Two distinct regimes are observed, each characterized by different power-law exponents.

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Abhishek Kumar Singh, Christopher Robert Kit Windows-Yule, Prapanch Nair. 2026-03-24. A numerical study on the coefficient of restitution of wet collisions. https://arxiv.org/abs/2603.23100

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