Unifying shear thinning behaviors of meso-scaled particle suspensions

Yuan Lin; Peiwen Lin; Yixuan Liang; Dingyi Pan

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arXiv · 2502.03857

Unifying shear thinning behaviors of meso-scaled particle suspensions

Yuan Lin·Peiwen Lin·Yixuan Liang·Dingyi Pan

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Abstract

The rheology of suspensions with meso-scaled particles [with size of $O(10^2)\ \text{nm}$ to $O(10)\ \mu\text{m}$] is intriguing since significant non-Newtonian behaviors are widely observed although the thermal fluctuation (Brownain motion) of the meso-scaled particles is negligible. Here, we show that the linear constitutive relation for such systems fails due to a flow-induced particle aggregation, which originates from the inherent inter-particle interactions, e.g., the weakly adhesive van der Waals interaction. This accounts for the temporal evolution of the rheological property in both steady and oscillatory shear flows. A dimensionless number that measures the importance of the hydrodynamic interaction in shear flow with respect to the inter-particle interaction, {is} proposed, through which the non-linear constitutive relation for suspensions with various particle sizes, particle concentrations, as well as flow conditions could be unified. This investigation bridge \mdf{the gap between micro- and macro-scaled suspension systems} and make the rheology of the meso-scaled suspensions predictable.

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Yuan Lin, Peiwen Lin, Yixuan Liang, Dingyi Pan. 2025-02-06. Unifying shear thinning behaviors of meso-scaled particle suspensions. https://arxiv.org/abs/2502.03857

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