THE NUMERICAL SIMULATION AND WIND TUNNEL EXPERIMENT ON WINDBLOWN SAND MOVEMENT OVER THE SLOPE SURFACE

The existing theory studies and numerical simulations of windblown sand movement have been concentrated in idealized circumstances, such as steady wind velocity, flat bed surface, etc. As a result, current theoretical and numerical models can not predict windblown sand saltating movement accurately. In this paper, wind tunnel experiments were carried out and the dust emission rate over slope surface was measured by using the Particle Image Velocimetry technique. Based on the wind tunnel experiment results, we built up a theoretical model and simulated the windblown sand movement with consideration of the coupling of wind and sand particles. The finite volume method was used to solve the N-S equation, and staircase grids were used to approach the real surface configuration. The results show that the numerical results are fairly consistent with corresponding experimental results. Then windblow sand saltating movement, such as the profiles of sand transport rate and wind speed at different positions over slop surface were discussed in details.