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arXiv · 1201.5562

Perfect fluid flow from granular jet impact

Jake Ellowitz·Nicholas Guttenberg·Wendy W. Zhang
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Abstract

Experiments on the impact of a densely-packed jet of non-cohesive grains onto a fixed target show that the impact produces an ejecta sheet comprised of particles in collimated motion. The ejecta sheet leaves the target at a well-defined angle whose value agrees quantitatively with the sheet angle produced by water jet impact. Motivated by these experiments, we examine the idealized problem of dense granular jet impact onto a frictionless target in two dimensions. Numerical results for the velocity and pressure fields within the granular jet agree quantitatively with predictions from an exact solution for 2D perfect-fluid impact. This correspondence demonstrates that the continuum limit controlling the coherent collective motion in dense granular impact is Euler flow.

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Jake Ellowitz, Nicholas Guttenberg, Wendy W. Zhang. 2012-01-26. Perfect fluid flow from granular jet impact. https://arxiv.org/abs/1201.5562

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