Equilibrium Saltation: Mass Fluxes, Aerodynamic Entrainment, and Dependence on Grain Properties

An examination is given of the way in which the saltation layer isaffected by the characteristics of the particles. Special attentionis given to the potential importance of aerodynamic entrainmentduring steady state saltation, a topic for which the discussion is still unresolved. A new numerical model for saltation in steady stateis presented, which is focused on the computation of the horizontalmass flux. The numerical computations, combined with physical arguments, suggest that aerodynamic entrainment plays a more important role thangenerally assumed so far. A comparison of the model results is made with previous models, and with measurements of snow saltation that have been reported in the literature.

[1]  J. C. R. Hunt,et al.  Saltation and incipient suspension above a flat particle bed below a turbulent boundary layer , 2000, Journal of Fluid Mechanics.

[2]  R. Stull An Introduction to Boundary Layer Meteorology , 1988 .

[3]  R. Bintanja Snowdrift suspension and atmospheric turbulence. Part I: Theoretical background and model description , 2000 .

[4]  Michael Lehning,et al.  Combining snow drift and SNOWPACK models to estimate snow loading in avalanche slopes , 2000 .

[5]  M. Sørensen An analytic model of wind-blown sand transport , 1991 .

[6]  John W. Pomeroy,et al.  Saltation of snow , 1990 .

[7]  I. McEwan Bagnold's kink: A physical feature of a wind velocity profile modified by blown sand? , 1993 .

[8]  Measurements and numerical simulations of snow-particle saltation , 1998 .

[9]  M. Raupach,et al.  Saltation layers, vegetation canopies and roughness lengths , 1991 .

[10]  Robert S. Anderson,et al.  Wind modification and bed response during saltation of sand in air , 1991 .

[11]  P. R. Owen,et al.  Saltation of uniform grains in air , 1964, Journal of Fluid Mechanics.

[12]  Robert S. Anderson,et al.  Sediment transport by wind: Toward a general model , 1986 .

[13]  J. C. R. Hunt,et al.  Saltating particles over flat beds , 1993, Journal of Fluid Mechanics.

[14]  Yaping Shao,et al.  Numerical Modelling of Saltation in the Atmospheric Surface Layer , 1999 .

[15]  H. Heywood The Physics of Blown Sand and Desert Dunes , 1941, Nature.

[16]  Mohamed Naaim,et al.  Numerical simulation of drifting snow: erosion and deposition models , 1998 .

[17]  P. Gauer Blowing and drifting snow in alpine terrain: A physically-based numerical model and related field measurements , 1999 .

[18]  M. A. Rice,et al.  Collisions of quartz grains with a sand bed: The influence of incident angle , 1989 .

[19]  I. McEwan,et al.  Numerical model of the saltation cloud , 1991 .