北京郊外近地面风场特性实测研究

基于北京延庆县某一近地风剖面观测点，观测获得了近地面冬季季风剖面实测数据，研究了近地风剖面的平均风速和风向角、湍流度、阵风因子、相干函数、湍流积分尺度和功率谱密度等风场特性参数，并与现行欧洲、美国、日本等相关国家规范进行了对比分析。研究结果表明：实测风速沿高度的变化规律除3.5m高度外，12.5m高度范围内实测结果与各国规范值基本符合；随着高度的增加，湍流度和阵风因子呈逐渐减小的趋势；实测湍流度结果与欧洲、美国、日本等相关规范湍流度取值较为接近，而与GB 50009-2012《建筑结构荷载规范》差异较大；10m高度范围内顺风向、横风向湍流积分尺度随着高度增加而增大，随着平均风速增大而增大，实测湍流积分尺度结果与国外规范值存在一定差异；随着测点间距增大，竖向相关性的衰减系数明显增大，且实测衰减系数结果与Davenport建议的衰减系数有明显差异；10m高度范围内各高度处的实测功率谱密度曲线基本一致，与已有经验谱有一定差异，但与Devenport谱接近。

Field measurements of wind characteristics near ground in Beijing suburbs

To explore the wind characteristics near ground, a 15m high meteorological mast located in Yanqing, Beijing was erected and four anemometers were arranged at 3.5m, 6.5m, 10m, 12.5m height, respectively. By the field measurements, longer time wind datum were acquired, and further analysis was conducted to obtain the mean wind and direction, turbulence intensity, gust factor, the turbulence integral length, coherence function, and wind power spectrum. The results demonstrate the mean wind is accorded with the value of various codes except at 3.5m height. The result of turbulence intensity and gust factor is reduced with height, and the measured turbulence intensity is close to the foreign standard but higher than the value recommended by GB 50009-2012. The turbulence integral scale is increased with mean wind speed but different from some codes’ recommended values. The decay coefficient of coherence function is varied with the distance, and an obvious contrast between the results of measurements and the recommendation value by Davenport was pointed out. A discrepancy between the measured and the typical wind power spectra is depicted.