基于大涡模拟特大型冷却塔风振系数取值研究

Research on Wind Vibration Coefficients of Super Large Cooling Towers Based on Larger Eddy Simulation

为研究200 m级特大型冷却塔风振系数取值问题,以国内在建的某特大型冷却塔(200 m)为例,采用大涡模拟(LES)方法获得该冷却塔表面三维气动力时程,并与国内外大型冷却塔实测结果对比,验证了数值模拟的有效性.在此基础上,结合有限元方法和风振时程分析理论对该冷却塔的动力特性、风振响应与风振系数进行了系统分析,提炼出此类特大型冷却塔二维风振系数的分布规律,最终给出了以正迎风面子午向轴力为目标的整体风振系数取值.所得出的主要研究结论可为此类200 m级超规范特大型冷却塔的风荷载设计取值提供参考.

With a under-constructed domestic 200 m large cooling tower as an example,the wind vibration coefficient of super large cooling towers was systematically studied. Numerical wind tunnel test was conducted by adopting the large eddy simulation（ LES） method to obtain the three-dimensional aerodynamic force time history. The outcomes of simulation were compared with that from field measurements and wind tunnels. The results showed the rationality of LES method. In this way,the dynamic property,wind-induced response and wind vibration coefficient were analyzed systematically. The regularities of distribution of two-dimensional wind vibration coefficient of 200 m super large cooling tower was extracted. Finally,the wind vibration coefficient of this super large cooling tower was suggested. These findings could provide scientific basis for the wind resistance design of such 200 m super large cooling towers.