考虑Ⅰ型支柱的超大型冷却塔风洞试验与风振系数研究

Wind Tunnel Test and Wind Vibration Coefficient of a Super-large Cooling Tower Considering I-type Pillars

超大型冷却塔结构的支柱截面构型和风振系数取值对其结构抗风稳定性尤为重要。依托安徽平山电厂二期国家最大火电机组超大型冷却塔示范工程,建立超大型冷却塔三维有限元精密化足尺模型,提出六种Ⅰ型支柱截面方案并探究其对结构模态、最小局部稳定因子和质量参与系数的影响,根据确定的截面方案建立冷却塔缩尺模型并开展刚体测压风洞试验,最终给出考虑Ⅰ型支柱的超大型冷却塔风振系数取值。研究表明不同支柱宽度最小局部稳定因子和前1000阶质量参与系数总和基本相同,Ⅰ型支柱宽度2m为超大型冷却塔支柱最优方案,单塔和最不利风向角下考虑Ⅰ型支柱的超大型冷却塔整体风振系数建议取值为1.77和1.95。研究结论可为此类超大型冷却塔支柱截面选型和结构抗风设计提供参考。

The type of pillars and the value of wind vibration coefficient of a super large cooling tower struc-ture are particularly important for its wind resistance stability.Based on the Anhui Pingshan Power Plant Phase II national largest thermal power unit super-large cooling tower demonstration project,a three-dimensional finite element precision full-scale model of the super-large cooling tower was established.Six I-type pillar cross-sec-tion schemes were proposed,and their effects on structural mode,minimum local stability factor and mass par-ticipation coefficient were explored.Based on the determined cross-section scheme,a scaled model of the cool-ing tower was established and rigid body pressure wind tunnel tests were conducted.Finally,the wind vibration coefficient value of a super-large cooling tower considering I-type pillars was given.It was shown that the mini-mum local stability factor for different column widths and the sum of the first 1000-order mass participation coef-ficients are basically the same.The I-type column width of 2m is the optimal solution for the super-large cooling tower column,and the recommended values for the overall wind vibration coefficient of the super-large cooling tower under single tower and the most unfavorable wind direction angle are 1.77 and 1.95 respectively.The re-search conclusion can provide a reference for the selection of the cross-section and structural wind resistance de-sign of such super-large cooling towers.