以拟建的山西临猗黄河大桥为工程背景,进行复杂地形桥位风场空间分布特性数值模拟研究。根据航天飞机雷达地形测绘使命(Shuttle Radar Topography Mission,SRTM)系统所提供的90 m分辨率数字地形高程模型,采用Global Mapper将桥位附近数字地形高程模型导出为点云图,再由逆向工程软件Imageware将桥位地形点云图生成曲面,采用GAMBIT建立桥位地形CFD模型,最后采用FLUENT软件进行桥位地形风场数值模拟。研究表明:采用SRTM所提供的90 m分辨率数字地形高程模型可实现复杂地形建模,且精度满足工程需要;4种网格计算结果总体上与实测值较为接近,最大相对误差约为-14.5%;风从正北方吹时,各监测点处平均风速沿高度增加而增大。
Taking Linyi Yellow River bridge to be built in the near future in Shanxi Province as engineering background,the numerical simulation of spatial distribution feature of wind field over bridge site at complex terrain is conducted. The digital elevation model with 90 m resolution of the bridge site given by Shuttle Radar Topography Mission( SRTM) is processed with Global Mapper to form the point cloud terrain map.The point cloud terrain map of the bridge site is then processed with inverse engineering software Imageware to form curved surface of the terrain map of the bridge site. The CFD model of the bridge site terrain is built with software GAMBIT based the curved surface. Finally,the numerical simulation of wind field over bridge site terrain is conducted with software FLUENT. The result shows that( 1) using the 90 m resolution digital terrain elevation model provided by SRTM can realize the modeling of complex terrain,and the model accuracy can meet the engineering needs;( 2) the numerical results of 4 grids are generally approach to the measured values with the maximum relative error of- 14. 5%;( 3) the average wind velocity at each monitoring point increases with the increasing of height when wind is blowing from the north.