中文摘要：

以某实际铀矿山为对象,运用CFD方法,基于N-S方程建立三维大气风场的物理模型,研究三种下垫面粗糙度下（z=0.1 m,z=0.5 m,z=1.0 m）的大气风场结构.结果显示,随着粗糙度增大,近地面风场速度变化达到19%;随着高度上升,大约在200 m后,粗糙度影响减弱,风场等值线趋于平稳;风场流速越大,近壁面处粗糙度对风场的阻碍作用越明显.在粗糙度较大（z≥0.5 m）情况下,可适当通过提高污染物排放高度来加强大气的输运能力,以缓解局部地区的污染。

英文摘要：

Based on N-S equation,uranium mine physical model was built and CFD methods were used to attain the air flow field under three surface roughness conditions（ z = 0. 1m,z = 0. 5 m,z = 1. 0 m）. Numerical results show that the surface wind speed change between two surface roughnesses is 19% with the roughness increasing. When the height is increased to 200 m,the effect of roughness is diminishing and the wind field contour line tends to be stable. The effect of the roughness to wind field near the ground is becoming more evident with the increase of wind speed. Raising the exhaust height could enhance the transport capacity in order to reduce local pollution level under the conditions of higher surface roughness（ z≥0. 5 m）.