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arXiv · 2002.10996

Shear thickening and jamming of dense suspensions: the "roll" of friction

Abhinendra Singh·Christopher Ness·Ryohei Seto·Juan J de Pablo·Heinrich M Jaeger
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Abstract

Particle-based simulations of discontinuous shear thickening (DST) and shear jamming (SJ) suspensions are used to study the role of stress-activated constraints, with an emphasis on resistance to gear-like rolling. Rolling friction decreases the volume fraction required for DST and SJ, in quantitative agreement with real-life suspensions with adhesive surface chemistries and "rough" particle shapes. It sets a distinct structure of the frictional force network compared to only sliding friction, and from a dynamical perspective leads to an increase in the velocity correlation length, in part responsible for the increased viscosity. The physics of rolling friction is thus a key element in achieving a comprehensive understanding of strongly shear-thickening materials.

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Abhinendra Singh, Christopher Ness, Ryohei Seto, Juan J de Pablo, Heinrich M Jaeger. 2020-02-25. Shear thickening and jamming of dense suspensions: the "roll" of friction. https://doi.org/10.1103/physrevlett.124.248005

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