摘要
以位于非洲摩洛哥的Noor Ⅲ光热电站吸热塔为工程背景。加拿大西安大略大学风洞实验室的试验表明该吸热塔在设计风速下的位移值超过规范值的40%,该结构的涡振临界风速小于设计风速,且涡振区横风向响应起控制作用。据此,在已有光热电站吸热塔气弹模型的基础上进行了风洞试验;在不同结构阻尼比下采集了15 min的模型顶部加速度时程;运用随机减量法和广义卡尔曼滤波法得到气动阻尼比。结果表明:两种方法识别的气动阻尼比吻合较好;在不同加速度幅值处识别的总阻尼比具有随加速度幅值的增大先增大后减小的规律;根据ASCE/SEI7-10,在重现周期为50年,C类地貌条件下,风速6. 5 m/s时识别的气动阻尼比为负的最小。这些规律为涡振区横风向响应起控制作用的现象提供了合理的解释。
Heat absorption tower of Noor Ⅲ solar thermal power station in Morocco,Africa was taken as engineering background. The wind tunnel test results at University of Western Ontario in Canada showed that the tower displacement value under the designed wind velocity is 40% higher than the code value,but the structure’s vortexinduced vibration（ VIV） critical wind speed is lower than the designed wind speed,and the response in crosswind direction within VIV area has a control action. Accordingly,an aero-elastic model for the tower was tested in wind tunnel.A 15 min-long acceleration time-history was collected at the top of the model under different structural damping ratios.Aerodynamic damping ratios were obtained using the random decrement technique and the extended Kalman filtering method,respectively. The results showed that aerodynamic damping ratios recognized with the two methods agree better each other; the total damping ratios recognized at different acceleration amplitudes firstly increase and then decrease with increase in acceleration amplitude; according to ASCE/SEI7-10,the identified aerodynamic damping ratio is negative and the minimum at wind speed of 6. 5 m/s under the recurrence period of 50-year and C geomorphologic condition; these laws provide a reasonable explanation for the phenomenon of the response in crosswind direction within VIV area having a control action.
作者
黄景辉
李寿英
刘敏
陈政清
回忆
李红星
HUANG Jinghui;LI Shouying;LIU Min;CHEN Zhengqing;HUI Y-i;LI Hongxing(Hunan Provincial Key Laboratory for Wind Engineering and Bridge Engineering,Hunan University,Changsha 410082,China;Northwest Electric Power Design Institute Co.,Ltd.,Xi＇an 710000,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2018年第21期177-183,共7页
Journal of Vibration and Shock
基金
国家自然科学基金(51578234)
国家重点基础研究发展计划(2015CB057702)
关键词
高耸结构
涡振
气动阻尼比
随机减量法
广义卡尔曼滤波法
towering structure
vortex induced vibration（VIV）
aerodynamic damping ratio
random decrement technique
extended Kalman filtering method
