Numerical model of the saltation cloud
A computer model of the saltation cloud is described. Experimental results from high speed films are used to characterise the grain/bed collision. The importance of momentum exchange in determining the number of ejected grains from a collision is demonstrated. The modification of the wind velocity profile is discussed and a realistic wind profile is calculated. Also the mass flux profiles calculated compare well to their expected shape. The model attains a steady state, characterised by a steady wind and a stationary grain population, after roughly 2 seconds. The response of the total mass flux to shear velocity is approximately cubic. Finally, potential uses of the model in studying ripple formation and dust emission are discussed.
KeywordsMass Flux Shear Velocity Wind Profile Impact Speed Saltation Layer
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