Eur. Phys. J. E (2007) 22: 195-200
https://doi.org/10.1140/epje/e2007-00028-7

Topical Issue on Dygram 2006

Aeolian transport of sand

¹ Departamento de Física, Universidade Federal do Ceará, Ceará, 60455-900, Fortaleza, Brazil
² Institute for Building Materials, ETH Zurich, Switzerland

^* e-mail: hjherrmann@ethz.ch

Received: 19 October 2006
Published online: 23 March 2007

Abstract

The airborne transport of particles on a granular surface by the saltation mechanism is studied through numerical simulation of particles dragged by turbulent air flow. We calculate the saturated flux q_s and show that its dependence on the wind strength u_* is consistent with several empirical relations obtained from experimental measurements. We propose and explain a new relation for fluxes close to the threshold velocity u_t, namely, q_s=a(u_*-u_t)^α with α≈2. We also obtain the distortion of the velocity profile of the wind due to the drag of the particles and find a novel dynamical scaling relation. We also obtain a new expression for the dependence of the height of the saltation layer as function of the strength of the wind.