Wall slip and bulk yielding in soft particle suspensions

Jung, Gerhard; Fielding, Suzanne M.

Abstract

We simulate a dense athermal suspension of soft particles sheared between hard walls of a prescribed roughness profile, fully accounting for the fluid mechanics of the solvent between the particles and for the solid mechanics of changes in the particle shapes. We, thus, capture the widely observed rheological phenomenon of wall slip. For imposed stresses below the material’s bulk yield stress, we show the slip to be dominated by a thin solvent layer of high shear at the wall. At higher stresses, it is augmented by an additional contribution from the fluidization of the first few layers of particles near the wall. By systematically varying the wall roughness, we quantify a suppression of slip with increasing roughness. We also elucidate the effects of slip on the dynamics of yielding following the imposition of constant shear stress, characterizing the timescales at which bulk yielding arises and at which slip first sets in.

Citation

Jung, G., & Fielding, S. M. (2021). Wall slip and bulk yielding in soft particle suspensions. Journal of Rheology, 65(2), Article 199. https://doi.org/10.1122/8.0000171

• Journal Article Type: Article
• Acceptance Date: Jan 21, 2021
• Online Publication Date: Feb 12, 2021
• Publication Date: 2021-03
• Deposit Date: Oct 14, 2021
• Publicly Available Date: Feb 12, 2022
• Journal: Journal of Rheology
• Print ISSN: 0148-6055
• Electronic ISSN: 1520-8516
• Publisher: American Institute of Physics
• Peer Reviewed: Peer Reviewed
• Volume: 65
• Issue: 2
• Article Number: 199
• DOI: https://doi.org/10.1122/8.0000171
• Related Public URLs: https://arxiv.org/abs/1911.05392