| Desertification is a very fateful environmental issue in the whole world. Wind erosion is one major form of the desertification. The change of wind field between the front and back of the plant is essential substance for the research of wind erosion. This master thesis used Realizable k-εmodel and Eulerian Two-phase Model to simulate three-dimensional turbulent flow number for single cylinder. I analyzed some situations:the cylinder diameter is 5mm,8mm and 10mm; inlet velocity is 7.3m/s and 10.2m/s; the volume fraction of sand is 0 (wind field),6% and 10%. The inlet velocity is received by calculated a quite long column-free area. The results were compared and analyzed:1. Along the height direction, the wind velocity is affected by the shear stress of bed. As the altitude increases, the wind velocity increases. Close to the bed, the shear stress reach to maximum and the wind velocity reach to minimum.2. Along the flow direction, since the change of wind velocity is mainly precluded by the cylinder, the change of wind velocity is great between the front and back of the cylinder. At the front of the cylinder, wind velocity is weaker than back of the cylinder. The closer to the cylinder, the greater to the influence for wind speed.3. The wind velocity is affected by cylindrical diameter, inlet velocity and volume fraction of sand. Even though at the same distance to the cylinder, the decrease range of wind velocity is different between the front and back of the cylinder.4. Because of cylindrical diameter and inlet velocity, the volume fraction of sands changes with the different regions.This master thesis analyzed the major factors that influent the change of wind velocity between the front and back of the cylinder, given the change trend of volume fraction of sands, and reflected the decreased range of the wind velocity under various situation. My research result is some reference value and practical significance for sand prevention and control project.
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