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Shocks in supersonic sand

E. Rericha·C. Bizon·M. D. Shattuck·H. L. Swinney
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Abstract

We measure time-averaged velocity, density, and temperature fields for steady granular flow past a wedge and calculate a speed of granular pressure disturbances (sound speed) equal to 10% of the flow speed. The flow is supersonic, forming shocks nearly identical to those in a supersonic gas. Molecular dynamics simulations of Newton's laws and Monte Carlo simulations of the Boltzmann equation yield fields in quantitative agreement with experiment. A numerical solution of Navier-Stokes-like equations agrees with a molecular dynamics simulation for experimental conditions excluding wall friction.

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E. Rericha, C. Bizon, M. D. Shattuck, H. L. Swinney. 2001-08-10. Shocks in supersonic sand. https://doi.org/10.1103/physrevlett.88.014302

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