Edge Fracture in Complex Fluids

Hemingway, Ewan J.; Kusumaatmaja, Halim; Fielding, Suzanne M.

Abstract

We study theoretically the edge fracture instability in sheared complex fluids, by means of linear stability analysis and direct nonlinear simulations. We derive an exact analytical expression for the onset of edge fracture in terms of the shear-rate derivative of the fluid’s second normal stress difference, the shear-rate derivative of the shear stress, the jump in shear stress across the interface between the fluid and the outside medium (usually air), the surface tension of that interface, and the rheometer gap size. We provide a full mechanistic understanding of the edge fracture instability, carefully validated against our simulations. These findings, which are robust with respect to choice of rheological constitutive model, also suggest a possible route to mitigating edge fracture, potentially allowing experimentalists to achieve and accurately measure flows stronger than hitherto possible.

Citation

Hemingway, E. J., Kusumaatmaja, H., & Fielding, S. M. (2017). Edge Fracture in Complex Fluids. Physical Review Letters, 119(2), Article 028006. https://doi.org/10.1103/physrevlett.119.028006

• Journal Article Type: Article
• Acceptance Date: Jul 14, 2017
• Online Publication Date: Jul 14, 2017
• Publication Date: Jul 14, 2017
• Deposit Date: Jul 17, 2017
• Publicly Available Date: Jul 17, 2017
• Journal: Physical Review Letters
• Print ISSN: 0031-9007
• Electronic ISSN: 1079-7114
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 119
• Issue: 2
• Article Number: 028006
• DOI: https://doi.org/10.1103/physrevlett.119.028006