English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Open

We study granular suspensions under a variety of extensional deformations andsimple shear using numerical simulations. The viscosity and Trouton's ratio(the ratio of extensional to shear viscosity) are computed as functions ofsolids volume fraction $\phi$ close to the limit of zero inertia. Suspensionsof frictionless particles follow a Newtonian Trouton's ratio for $\phi$ all theway up to $\phi_0$, a universal jamming point that is independent ofdeformation type. In contrast, frictional particles lead to adeformation-type-dependent jamming fraction $\phi_m$, which is largest forshear flows. Trouton's ratio consequently starts off Newtonian but diverges as$\phi\to\phi_m$. We explain this discrepancy in suspensions of frictionalparticles by considering the particle arrangements at jamming. Whilefrictionless particle suspensions have a nearly isotropic microstructure atjamming, friction permits more anisotropic contact chains that allow jamming atlower $\phi$ but introduce protocol dependence. Finally, we provide evidencethat viscous number rheology can be extended from shear to extensionaldeformations, with a particularly successful collapse for frictionlessparticles. Extensional deformations are an important class of rheometric flowin suspensions, relevant to paste processing, granulation and high performancematerials.

Rheology of dense granular suspensions under extensional flow