我国冷却塔规范风荷载条款仍源自20世纪80年代原型冷却塔(约90m高)实测资料,且仅规定了塔筒表面静态风压分布。事实上,超大型冷却塔(高度≥165m)风振问题与风荷载脉动作用关系更加密切,由此导致了冷却塔数学和物理试验模型雷诺数效应模拟准则的不完整性,难于准确再现冷却塔表面动态风荷载与来流条件、塔群组合状况等参数间的合理关系,已成为制约大型冷却塔抗风性能研究和结构设计的瓶颈。为此,采用全天候动态风压采集设备,对某电厂冷却塔(约166m高)进行通风筒表面动、静态风压长期现场观测,量化表面脉动压力与来流紊流度之间的影响关系,提出具有原创性的冷却塔超高雷诺数条件(Re≥6E7)脉动风压雷诺数效应模拟准则。
The items for wind loads in Chinese Cooling Tower Codes came from the measured data of full-scale cooling tower (with a height of about 90m) in 1980's, and only static pressure distributions with polynomial expressions on the surface of tower shaft were proposed. In fact, for superlarge cooling tower (with a height of no less than 165m) , the wind vibration problem shall be closely related to the fluctuating effects of wind loads. Due to the incompleteness of simulation rules on Reynolds number in physical and mathematical test models of superlarge cooling tower, the difficulty in reproducing the rational relations between the dynamic wind loads on the surface of tower shell and those parameters such as incoming flow conditions and combination types of tower groups has become a bottleneck problem of studying the wind-resistant performance and the structural design of superlarge cooling tower. Therefore, all-weather data measurement for a superlarge cooling tower ( with a height of about 166m) in Xuzhou was conducted. Based on the long- term field observation for the static and dynamic wind pressures on the surface of tower shell, the influence relations between the surface fluctuating wind pressure and the turbulence intensity of incoming flow were quantified. And, a novel simulation rule was proposed for the fluctuating wind pressure under supercritical Reynolds number (Re 〉 6E7 ).