Numerical prediction on erosion damage caused by wind-blown sand movement

Abstract

This study quantitatively investigated the erosion damage on the metal material caused by wind-blown sand under different environmental conditions (e.g. height and wind velocity) in aeolian processes. Wind-blown sand causes destructive impacts on buildings, abrasion of crops and many other damages in arid regions. Sand transport caused by wind often appears in the desert, open-pit mines and coastal dune fields, which is a special case of two-phase flow of gas and solids. Due to its special dynamic characteristics, the sand–wind system near the bed surface is complex and difficult to be solved by traditional computational fluid dynamics method. However, the steady-state saltation model is effective for describing the wind-blown sand movement. Therefore, this paper combines the solid particles erosion model with the steady-state saltation model to predict the erosion damages caused by blown sand. Correctness of the algorithm has been verified through the comparison of simulated results and experimental data of the sand flow structure. An early conclusion that the kinetic energy is crucial to erosion has been proved in this paper. The results show that the erosion rate varies with different variables, e.g. saltating velocity, saltating height, length, etc. The quantity of erosion shows stratification pattern as well as the mass flux of the sand flow. These results quantitatively show the major features of the erosion caused by wind-blown sand.