近地边界层台风观测及湍流特征参数分析

Monitoring of typhoons in surface boundary layer and analysis of wind turbulence characteristics

通过近海岸测风塔获取了台风达维(0518)、珍珠(0601)、派比安(0606)登陆过程中10m高度三维脉动风速数据,对近地10m高度平均风特性和湍流特性进行了分析和研究。基于台风观测结果,分析了不同来流方向和地貌状况下,风剖面指数值、摩擦速度、湍流度和阵风因子等湍流参数及其相关性。分析结果表明:摩擦速度与平均风速呈正相关,摩擦速度随平均风速增大而增大;风剖面指数值随平均风速增大而减小;各方向湍流度随平均风速增大而减小;阵风因子与湍流度呈线性关系。通过拟合实测湍流参数相关性,提出了10m标准高度台风湍流度、阵风因子的计算式,可为台风多发区域低矮房屋的抗风设计提供参考。

Mean wind speed and wind turbulence characteristics of typhoon winds in surface boundary layer were studied based on three-dimensional wind data,which were recorded from ultrasonic anemometers at 10m height at sites near seashore during land falling of Typhoons Damrey,Chunchu and Paipiroon.The relations among turbulence parameters such as power law index,friction velocity,turbulence intensities and gust factor were analyzed under different types of upwind terrains based on the field measurements results.The results of the analysis reveal that friction velocity strongly depends on mean wind speed,which increases with increasing wind speed.Power law index and turbulence intensities decrease with the increasing of wind speed.Gust factor increases with the increasing of turbulence intensities.By fitting the results of turbulence parameters,the relations among the parameters were proposed which will be useful for the wind resistant design of low rise buildings in typhoon-prone regions.