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Aeolian transport layer

M. P. Almeida·J. S. Andrade Jr.·H. J. Herrmann
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Abstract

We investigate the airborne transport of particles on a granular surface by the saltation mechanism through numerical simulation of particle motion coupled with turbulent flow. We determine the saturated flux $q_{s}$ and show that its behavior is consistent with a classical empirical relation obtained from wind tunnel measurements. Our results also allow to propose a new relation valid for small fluxes, namely, $q_{s}=a(u_{*}-u_{t})^α$, where $u_{*}$ and $u_{t}$ are the shear and threshold velocities of the wind, respectively, and the scaling exponent is $α\approx 2$. We obtain an expression for the velocity profile of the wind distorted by the particle motion and present a dynamical scaling relation. We also find a novel expression for the dependence of the height of the saltation layer as function of the wind velocity.

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M. P. Almeida, J. S. Andrade Jr., H. J. Herrmann. 2005-05-25. Aeolian transport layer. https://doi.org/10.1103/physrevlett.96.018001

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