Dynamical fluctuations in dense granular flows
نویسندگان
چکیده
منابع مشابه
Dynamical fluctuations in dense granular flows.
We have made measurements of force and velocity fluctuations in a variety of dense, gravity-driven granular flows under flow conditions close to the threshold of jamming. The measurements reveal a microscopic state that evolves rapidly from entirely collisional to largely frictional, as the system is taken close to jamming. On coarse-grained time scales, some descriptors of the dynamics-such as...
متن کاملDense Granular Flows down Inclines
Dense granular flows down inclines continue to defy understanding. However, the last three decades have witnessed progress in techniques and approaches that have moved the field closer to achieving ab initio predictions of practical relevance. Difficulties arise for three principal reasons. First, because granular flows dissipate mechanical energy on the particle scale, regions featuring a subs...
متن کاملVelocity correlations in dense granular flows.
Velocity fluctuations of grains flowing down a rough inclined plane are experimentally studied. The grains at the free surface exhibit fluctuating motions, which are correlated over a few grain diameters. The characteristic correlation length is shown to depend on the inclination of the plane and not on the thickness of the flowing layer. This result strongly supports the idea that dense granul...
متن کاملClusters in dense-inertial granular flows
In the dense-inertial regime of granular flow, the stresses scale inertially, but the flow is dominated by clusters of particles. This paper describes observations of cluster development in this regime. Clusters were seen to form for both elastic and inelastic reasons: elastic when the shear rate pushes the particles together faster than the contacts can elastically disperse them, and inelastic...
متن کاملEffective boundary conditions for dense granular flows.
We derive an effective boundary condition for dense granular flow taking into account the effect of the heterogeneity of the force network on sliding friction dynamics. This yields an intermediate boundary condition which lies in the limit between no slip and Coulomb friction; two simple functions relating wall stress, velocity, and velocity variance are found from numerical simulations. Moreov...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
سال: 2009
ISSN: 1364-503X,1471-2962
DOI: 10.1098/rsta.2009.0189