摘要
为研究台风登陆过程中近地风场脉动特性,采用Windcube V2型多普勒激光测风雷达实测台风“海马”的登陆过程,获得了高度40-290 m范围内共计12处的时程数据。基于观测结果,分析了台风中心、眼壁强风区等位置的平均风速和风向、风剖面、阵风因子、湍流强度、湍流积分尺度等发散特性。分析结果表明：台风“海马”平均风速时程呈“M”形双峰分布,台风登陆前后风向角变化了近180°;平均风速剖面在风眼中心和眼壁强风区具有明显不同的剖面形式;风向剖面异于良态风剖面,且沿高度并非一致;在台风眼壁强风区,纵、横和竖向湍流强度三者之比为1∶0.91∶0.40,相比于规范值,台风“海马”横向湍流强度相对较大,竖向湍流强度相对较小;纵向和横向阵风因子均随平均风速的增加而减小,基于非线性关系式给出了阵风因子和湍流度的拟合关系式,拟合结果与实测结果较为接近;湍流积分尺度在眼壁强风区较大,台风登陆前后其值差异也较大且后眼壁大于前眼壁,受地貌特性影响较为显著。
In order to understand the turbulence characteristics of near-surface wind field during the typhoon landing, the time history data about the landing progress of typhoon ＇ Haima＇ was obtained by using Windcube V2 Doppler lidar, and the data of 12 measuring points between 40-290 ra height was obtained. Based on the observation results, the mean wind speed and wind direction, wind profile, gust factor, turbulence intensity and turbulence integral scale in the typhoon center and the strong wind area of the eye wall were analyzed. The results show that the mean wind speed of typhoon ＇ Haima＇ has an ＇M＇ bimodal distribution, and the wind direction changes nearly 180~ before and after the typhoon landfall. The mean wind speed profile has obvious different types in the typhoon center and the eye wall strong wind area; the wind direction profile is different between the typhoon and the monsoon, also, the wind direction profile is not uniform along the height. The ratio of turbulence intensity in the longitudinal, lateral and vertical direction is 1 ： 0. 91 ： 0. 40 in eye wall strong wind region, the lateral turbulence intensity of the typhoon ＇ Haima＇ is larger and the vertical turbulence intensity is smaller compared with the standard value. The longitudinal and lateral gust factors reduce with the increase of the wind speed, the fitting formula between them was obtained by the non-linear relationship, and the resuks show that the fitting results are close to the measured data. The turbulence integral scale is larger in the strong wind area of the eye wall and changes greatly before and after the typhoon landed, also, the turbulent integral scale of the posterior eye wall is larger than that of the anterior eye wall, which is obviously affected by the landform characteristics.
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2018年第1期28-34,共7页
Journal of Building Structures
基金
广东电网公司重点科技项目(GDKJQQ20153009)
关键词
台风海马
现场实测
台风中心
近地层
湍流特性
typhoon Haima
field measurement
typhoon center
near ground layer
turbulence characteristic
