Flow Field Simulation And Sand Flux Computation Of Complex Terrain

At present the study of the movement of sands mainly focuses on theoretical analysis of and numerical simulations of blown sand on the flat bed of sand. But theoretical analysis of and numerical simulations of the movement of sands on the complex terrain and sand dunes are relative few. In this paper the work that is two important issues of the study of sands is done: one is using Fluent numerically simulated several kinds of representative flow field at the conditions of the complex microtopography and calculated the several kinds of the representative rate of the single-point sediment at different wind conditions. Another is using Fluent numerically simulated the flow field of the sand dune under different inflows and numerically simulated the rate of the sediment at the specific location of the sand dune.In the first part of this dissertation, this dissertation simulated the flow field of complex microtopography under the condition of the several representative inflows during sandstorm. Compared to the field measurements of flow, it suggests that the simulated results in dissertation are reasonable. Through the calculation error of wind simulation, it shows that the simulated results have high accuracy. Furthermore, it also proves that the calculated results of the sand transport rate of the two models are good accordance and the upper microtopography of the wind speed measurement point has pivotal influence on the sand transport rate of that point.In the second part of research contents, this dissertation has carried on the numerical simulation to the sand dune at different inflows condition during duration time of sandstorm. The results of numerical simulation to the flow field show rationality through comparison of the flow field simulation results and measurement results at different inflows condition; it shows that the simulation of flow field is basically satisfactory in precision through the calculation of the wind speed, but the simulation of the wind direction is relatively bad in precision. Compare to the simulation and measurement of the sand flux, we know simulation results are better accordance with the experimental results. Moreover, we also find the sand flux and sand transport rate getting from the two models are very close.