We study the rheological properties of a granular suspension subject to constant shear stress by constant volume molecular dynamics simulations. We derive the system ‘‘flow diagram’’ in the volume fraction or stress plane (, F): at low the flow is disordered, with the viscosity obeying a Bagnold-like scaling only at small F and diverging as the jamming point is approached; if the shear stress is strong enough, at higher an ordered flow regime is found, the order-disorder transition being marked by a sharp drop of the viscosity. A broad jamming region is also observed where, in analogy with the glassy region of thermal systems, slow dynamics followed by kinetic arrest occurs when the ordering transition is prevented.
Flow, Ordering and Jamming of Sheared Granular Suspensions / D. S., Grebenkov; PICA CIAMARRA, Massimo; Nicodemi, Mario; Coniglio, Antonio. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - 100:(2008), pp. 7801-1-7801-3. [10.1103/PhysRevLett.100.078001]
Flow, Ordering and Jamming of Sheared Granular Suspensions
PICA CIAMARRA, MASSIMO;NICODEMI, MARIO;CONIGLIO, ANTONIO
2008
Abstract
We study the rheological properties of a granular suspension subject to constant shear stress by constant volume molecular dynamics simulations. We derive the system ‘‘flow diagram’’ in the volume fraction or stress plane (, F): at low the flow is disordered, with the viscosity obeying a Bagnold-like scaling only at small F and diverging as the jamming point is approached; if the shear stress is strong enough, at higher an ordered flow regime is found, the order-disorder transition being marked by a sharp drop of the viscosity. A broad jamming region is also observed where, in analogy with the glassy region of thermal systems, slow dynamics followed by kinetic arrest occurs when the ordering transition is prevented.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.