STUDY ON THE BOUNDARY LAYER WIND VARIATION CHARACTERISTICS OF SUPER-TYPHOON RAMMASUN DURING LANDING ON XUWEN COUNTY

WANG Hai-long; WU Xin-qiao; HUANG Zeng-hao; CAI Yan-feng; ZHANG Can-heng

doi:10.16032/j.issn.1004-4965.2018.03.002

Abstract：On the basis of observed wind speed and direction data at Yongshi Wind Farm during the landing of super-typhoon Rammasun on Xuwen county, Guangdong province, wind shear, gust factor, turbulence intensity and wind direction of Rammasun are analyzed to support the design of high-voltage overhead transmission lines and selection of wind turbines for the southeast coast of China that is seriously affected by typhoons. It was found that wind shear index was less than frontal wind, and first decreased and then increased when the typhoon eye approached and then left the observation site. When the typhoon eye went through the observation site and wind direction changed to the southward, wind shear profile did not fit the power law. The gust factor reduced with height, which complied with the power law perfectly when the typhoon eye was going toward to the mast, but did not present such rule any more after the typhoon eye left. The gust factor and its difference between layers decreased when the typhoon eye came close and wind speed increased, but they increased after the typhoon eye left. The turbulence intensity decreased with height. When it comes to temporal variation, the turbulence intensity was smaller and the change was correspondingly steady. Most of the turbulence intensity at the hub height was less than the IEC-B standard.The wind veered from the north to the northeast, then to the east and finally to the south-southeast, presenting a clockwise rotation relative of the station which was at the right side of the typhoon eye-wall.