连云港沿海近地层湍流强度特征

Analysis of Surface Layer Turbulence Intensity along Lianyungang Coastland

在对连云港沿海15个各类气象观测站2000—2009年8级以上强风样本统计分析基础之上,利用6座沿海梯度测风塔2005—2007年测风资料,探讨了连云港沿海近地层风湍流强度的时空分布规律及特点,并重点对不同类型天气系统引起的强风湍流演变特征及其对风电场影响进行剖析。研究结果表明:①风湍流强度具有很强的季节性,冬季小、夏季大,随高度增加而减小;②海面动力粗糙度对海上强湍流变化的影响有别于无强风及下垫面是陆地时;③在热带气旋影响区域,同一时段内可能会出现风速和湍流强度瞬时骤变现象;④海上强湍流出现在30m以上高度,陆地出现在底层,这一现象在不同天气系统引起的强风湍流变化中都有发现;⑤风机轮毂高度处有2.1%～3.8%的湍流强度特征值超过目前风机最大抗湍流强度设计标准,建议华东中、北部沿海地区风机抗湍流强度参数调整为0.31～0.41。

Based on the statistical results of strong winds（above Grade 8 in Beaufort scale） from 15 meteorological observation stations from 2000 to 2009,the spatial-temporal distribution feature of wind turbulence intensity at the Lianyungang＇s coastal region is discussed with wind data from 6 wind gradient towers around the coastal region of Lianyungang from 2005 to 2007.The characteristics of strong wind turbulence intensity caused by different weather systems and their influence on wind farm are analyzed.The results show that the wind turbulence intensity has obvious seasonal change,larger in summer and smaller in winter,decreasing with increasing altitude;the influence of surface roughness over the sea on strong turbulence is different from that over land with breeze;wind and turbulence intensity may change suddenly in the same time in the tropical cyclone region;the strong turbulence appears usually above the altitude of 30 m over sea and near the ground on land respectively,which is also found in strong wind turbulence caused by different weather systems;and the characteristic value of 2.1% to 3.8% turbulence intensity exceeds the design criterion of the maximum turbulence intensity for fans at the altitude of fan wheels,which suggests that the parameter of fan maximum turbulence intensity should be adjusted to 0.31 to 0.41 around the coastal region of the central and northern parts of East China.