title: Still water: dead zones and collimated ejecta from the impact of granular jets.
abstract: When a dense granular jet hits a target, it forms a large dead zone and ejects a highly collimated conical sheet with a well-defined opening angle. Using experiments, simulations, and continuum modeling, we find that this opening angle is insensitive to the precise target shape and the dissipation mechanisms in the flow. We show that this surprising insensitivity arises because dense granular jet impact, though highly dissipative, is nonetheless controlled by the limit of perfect fluid flow.
authors.affiliation: Department of Physics and the James Franck Institute, University of Chicago, Chicago, Illinois 60637, USA.
authors.forename: Jake
authors.initials: J
authors.lastname: Ellowitz
authors.forename: Hervé
authors.initials: H
authors.lastname: Turlier
authors.forename: Nicholas
authors.initials: N
authors.lastname: Guttenberg
authors.forename: Wendy W
authors.initials: WW
authors.lastname: Zhang
authors.forename: Sidney R
authors.initials: SR
authors.lastname: Nagel