Granular fluidity in cohesive split-bottom granular flows
Phys. Rev. Fluids 7, 084306 – Published 31 August, 2022
DOI: https://doi.org/10.1103/PhysRevFluids.7.084306
Abstract
Despite important progresses in recent continuum modeling, most nonlocal rheologies remain exclusive to dry granular flows. Indeed, popular theories such as nonlocal granular fluidity (NGF) are only valid for dry materials and extensions for wetted particles have yet to be proposed. To address such shortcomings, a detailed analysis of the split-bottom geometry subject to capillary forces is presented. The principal features of such flow are explained and highlighted using a coarse-graining procedure. In particular, the granular fluidity field from the NGF theory is examined and its relationship with the cohesiveness of the material is explored through the dimensionless Bond number. By limiting the scope to critical-state areas and using normalizations based on the granular temperature, exponential-type cohesive constitutive laws have been obtained. This work deepens the current understanding of cohesive granular flows, brings the construction of a cohesive nonlocal rheology one step closer, and leads the way toward a unification of both NGF and kinetic theory frameworks.
