Criteria for Shear Banding in Time-Dependent Flows of Complex Fluids

Moorcroft, R.L.; Fielding, S.M.

Abstract

We study theoretically the onset of shear banding in the three most common time-dependent rheological protocols: step stress, finite strain ramp (a limit of which gives a step strain), and shear startup. By means of a linear stability analysis we provide a fluid-universal criterion for the onset of banding for each protocol, which depends only on the shape of the experimentally measured time-dependent rheological response function, independent of the constitutive law and internal state variables of the particular fluid in question. Our predictions thus have the same highly general status, in these time-dependent flows, as the widely known criterion for banding in steady state (of negatively sloping shear stress vs shear rate). We illustrate them with simulations of the Rolie-Poly model of polymer flows, and the soft glassy rheology model of disordered soft solids.

Citation

Moorcroft, R., & Fielding, S. (2013). Criteria for Shear Banding in Time-Dependent Flows of Complex Fluids. Physical Review Letters, 110(8), Article 086001. https://doi.org/10.1103/physrevlett.110.086001

• Journal Article Type: Article
• Publication Date: Feb 1, 2013
• Deposit Date: Mar 19, 2013
• Publicly Available Date: Jun 3, 2014
• Journal: Physical Review Letters
• Print ISSN: 0031-9007
• Electronic ISSN: 1079-7114
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 110
• Issue: 8
• Article Number: 086001
• DOI: https://doi.org/10.1103/physrevlett.110.086001
• Public URL: https://durham-repository.worktribe.com/output/1464302