基于六旋翼无人机搭载风速仪的典型建筑绕流实测

MEASUREMENT OF FLOW AROUND A TYPICAL BUILDING BASED ONSIX-ROTOR UAV ANEMOMETER

基于无人机搭载风速仪对边界层内典型建筑的绕流风场风特性进行了实测研究,分析了平均风速、湍流度、脉动风速功率谱等风场风特性参数。分析结果表明:基于无人机实测拟合的建筑来流剖面粗糙度指数为0.2796,处于GB 50009-2012《建筑结构荷载规范》中的C类地貌与D类地貌之间;来流处顺风向和横风向脉动风速功率谱与Karman谱较为吻合,横风向脉动风速功率谱峰值能量略高于经验谱。本次实测建筑高度为82.45 m,现场实测表明在60 m和80 m高度平面的绕流风场特性受建筑影响较为明显,受影响区域主要为建筑两侧靠近建筑的区域以及尾流中间段区域,这些区域测点的平均风速较之来流减小,顺风向和横风向湍流度较之来流增大;受建筑影响区域的顺风向和横风向脉动风速功率谱峰值具有向高频段移动的趋势;而在100 m、120 m高度的现场实测表明,这两个平面绕流风场特性受建筑影响较小。

Based on the UAV-mounted anemometer,the wind characteristics of the wind field around a typical building in its boundary layer were measured and studied,and the wind characteristics parameters were analyzed,such as average wind speed,turbulence and,fluctuating wind speed power spectrum.The results show that the roughness index of the building incoming flow profile based on UAV measurement is 0.2796,which is between class C landform and Class D landform in China's code(GB 50009−2012"Load code for the design of building structures").The pulsating wind speed power spectrum in the downwind and crosswind directions at the incoming flow is in a good agreement with the Karman spectrum,and the peak energy of the pulsating wind speed power spectrum in the crosswind direction is slightly higher than that of the empirical spectrum.The measured building height is 82.45 m.The field measurement shows that the wind field characteristics at 60 m and 80 m are significantly affected by the building.The affected areas are mainly the areas near the building on both sides of the building and the areas in the middle section of the wake.Compared with the oncoming flow,the average wind speed of the measuring points in these areas decreases,and the turbulence in the downwind and crosswind directions increases.The peak values of wind power spectrum of downwind and transverse wind in the area affected by the building tend to move to the high frequency band.The field measurements at 100 m and 120 m show that the wind field characteristics of these two planes are less affected by the building.