工程常见塔间距下大型冷却塔的双塔干扰效应

摘要

Wind tunnel tests were employed to study the wind-induced interference effects on two adjacent large cooling towers with different tower distances that are commonly used in engi-neering practice.The technique of adding roughness on model surface was applied to compensate for the Reynolds number effect due to model-scale tests.The wind tunnel tests of 125 test cases with different tower distances and wind azimuths were carried out.The wind-induced responses of cooling tower were obtained using the Finite Element analysis.The overall wind loads and wind-induced responses with respect to tower distance and wind azimuth were calculated and in-terference effects on two towers are then studied.Results show that if two towers are in tandem arrangement,the interference factors of along-wind base shear will be greater than 1,which can be considered as results of the Venturi effect.Furthermore,if the tower distance is smaller,the interference effects will be much more significant.Considering the tower distances investigated in the paper,the maximum interference factors based on various effects including overall wind loads and wind-induced responses are about 1.15.The wind azimuth when the interference factors of a-long-wind base shears and base bending moments reach their maximum values is at about 67.5°. However,the wind azimuth when the interference factors of wind-induced responses reach their maximum values is between 90°and 150°respectively.%针对工程常见塔间距下冷却塔双塔干扰效应采用风洞试验方法进行研究，通过增加模型表面粗糙度来补偿模型试验的雷诺数效应，变化塔间距和风向角进行125种工况的风洞试验，进行基于有限元的风致响应计算，获得不同风向角和塔间距下的整体风荷载和风致响应，并以此进行双塔的干扰效应研究。研究发现双塔并行放置时，由于“狭缝效应”的存在使得顺风向塔底剪力的干扰系数大于1，此时塔间距越小，干扰效应越显著；本文研究的塔间距下基于多组风荷载和风致响应指标的干扰系数最大值约为1．15；顺风向塔底剪力和弯矩的干扰系数最大值大约出现在67．5°风向，基于风致响应指标的最大值出现在90°≤θ≤150°之间的风向。