Vertical distribution of saltating particles in a windsand flux
R.A. Gushchin, G.I. Gorchakov, A.V. Karpov, O.I. Datsenko
A.M. Obukhov Institute of Atmospheric Physics Russian Academy of Sciences, Moscow, Russia
Keywords: windsand flux, saltation, concentration of saltating particles, mass flux of particles, vertical profile, piecewise exponential approximation, height scale, thickness of the lower layer of saltation
Abstract
Using data from experimental studies in a desertified area and in a wind channel, patterns of vertical distribution of saltating particles in a wind-sand flux have been established, which are necessary for understanding the dynamic and electrical processes in a wind-sand flux. Investigation of the influence of wind velocity in the surface air layer on the vertical distribution of saltating particles in a windsand flux in a desertified area has been carried out. A piecewise exponential approximation of vertical particle concentration profiles with a wind speed-independent height scale and a logarithmic concentration gradient in the lower saltation layer is proposed. Using measurements in the wind channel of saltation particle flux profiles, the dependences of the thickness of the lower saltation layer and the height scale for the mass flux of particles in the lower saltation layer on the size of the saltation particles in the range from 100 to 800 mm are obtained. It is shown that the results of determining the parameters of the windsand flux in the desertified area and in the wind channel are consistent with each other. Our results can be used for modeling the dynamics of wind-sand flux.
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