title: From frictional to viscous behavior: three-dimensional imaging and rheology of gravitational suspensions.
abstract: We probe the three-dimensional flow structure and rheology of gravitational (nondensity matched) suspensions for a range of driving rates in a split-bottom geometry. We establish that for sufficiently slow flows, the suspension flows as if it were a dry granular medium, and confirm recent theoretical modeling on the rheology of split-bottom flows. For faster driving, the flow behavior is shown to be consistent with the rheological behavior predicted by the recently developed "inertial number" approaches for suspension flows.
authors.affiliation: Kamerlingh Onnes Lab, Universiteit Leiden, Postbus 9504, 2300 RA Leiden, The Netherlands.
authors.forename: Joshua A
authors.initials: JA
authors.lastname: Dijksman
authors.forename: Elie
authors.initials: E
authors.lastname: Wandersman
authors.forename: Steven
authors.initials: S
authors.lastname: Slotterback
authors.forename: Christian R
authors.initials: CR
authors.lastname: Berardi
authors.forename: William Derek
authors.initials: WD
authors.lastname: Updegraff
authors.forename: Martin
authors.initials: M
authors.lastname: van Hecke
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Losert