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Still water: dead zones and collimated ejecta from the impact of granular jets
Jake Ellowitz1, Hervé Turlier, Nicholas Guttenberg
1Department of Physics and the James Franck Institute, University of Chicago, Chicago, Illinois 60637, USA.
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.
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