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arXiv · 1104.2767

Jump at the onset of saltation

M. V. Carneiro·T. Pähtz·H. J. Herrmann
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Abstract

We reveal a discontinuous transition in the saturated flux for aeolian saltation by simulating explicitly particle motion in turbulent flow. The discontinuity is followed by a coexistence interval with two metastable solutions. The modification of the wind profile due to momentum exchange exhibits a second maximum at high shear strength. The saturated flux depends on the strength of the wind as $q_s=q_0+A(u_*-u_t)(u_*^2+u_t^2)$.

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M. V. Carneiro, T. Pähtz, H. J. Herrmann. 2011-08-24. Jump at the onset of saltation. https://doi.org/10.1103/physrevlett.107.098001

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