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arXiv · 2311.14408

Localized jammed clusters persist in shear-thickening suspension subjected to swirling excitation

Li-Xin Shi·Song-Chuan Zhao
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Abstract

We investigate the dynamic evolution of heterogeneity in shear-thickening suspensions subjected to swirling excitation with a free surface. The uniform state of such a system may lose its stability when the oscillation frequency is above a threshold, and density waves spontaneously form (Shi \textit{et al.} JFM 2024). Here, we report a novel state where jammed clusters emerge in high-density region of the density waves. The jammed cluster exhibits unique motion, creating downstream high-density regions distinct from previously reported state of density waves. Additionally, theoretical calculations show that reducing suspension thickness lowers the frequency and global concentration $\Phi$ threshold for the heterogeneity onset. Notably, the minimal $\Phi$ for instability can be lower than the onset of discontinuous shear thickening transition. We also highlight the role of the free surface in cluster growth and persistence.

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Li-Xin Shi, Song-Chuan Zhao. 2023-11-24. Localized jammed clusters persist in shear-thickening suspension subjected to swirling excitation. https://doi.org/10.1103/physrevfluids.9.083301

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