An analytic expression for wind-velocity profile within the saltation layer

The vertical wind-velocity profile within the saltation layer is investigated theoretically. New equations for the fluid shear stress distribution in the saltation layer and the velocity profile affected by saltation are derived. The dependence of the velocity profile on the threshold shear velocity, the vertical variations of sand grain velocity, the vertical sand-mass-flux distribution, and the fluid shear stress within the saltation are demonstrated. Velocity profiles with or without Bagnoldʹs focus are predicted. These velocity profiles are not very sensitive to the vertical distribution of sand-mass flux. Predicted velocity profiles are compared with profiles measured in the wind tunnel, and satisfactory agreement has been achieved.