输电导线气动阻尼效应的风洞试验研究  

Aerodynamic damping effects of a transmission conductor by wind tunnel tests

作　　者：王述良[1] 梁枢果[1] 邹良浩[1] 汪大海[2] 

机构地区：[1]武汉大学土木建筑工程学院,武汉430072 [2]武汉理工大学土木工程与建筑学院,武汉430070

出　　处：《振动与冲击》2016年第20期30-36,53,共8页Journal of Vibration and Shock

基　　金：国家自然科学基金项目(51078296)

摘　　要：基于单跨六分裂输电导线气弹模型风洞试验,测得了不同风速下输电导线端部,即输电导线传递给输电塔的动张力时程,结合经验模态分解法(EMD)、小波分析及随机减量法(RDT)识别了输电导线的前四阶气动阻尼比,并将其与基于准定常理论的气动阻尼比进行了对比。考虑气动阻尼的影响,对输电导线动张力进行了计算。研究结果表明:输电导线的气动阻尼相对于结构阻尼,占有主导地位,在强风下可以达到结构阻尼比的10倍以上;由于输电导线的风致非线性振动,使得基于准定常理论的气动阻尼比与识别结果相比存在显著差异;强风作用下,不考虑气动阻尼比的计算结果将严重地高估输电导线的风致动张力响应。Based on aero-elastic model wind tunnel tests of a single-span six-bundled transmission conductor, timeseries of dynamic tensions at the end of the conductor under various wind speeds, namely the force transmitted to the tower, were measured by the force balances. Through the dynamic tensions, the first four modal aerodynamic damping ratios were evaluated by combining the empirical mode decomposition （ EMD） method, wavelet analysis, and random decrement technology （ RDT） . The results were compared with those obtained by quasi-steady theory. Then, considering the effects of aerodynamic damping, wind-induced responses were calculated. The results illustrate that aerodynamic damping is dominant relative to the structural damping, which may reach more than ten times of structural damping ratio; due to the wind-induced nonlinear vibration of the conductor, the discrepancy of aerodynamic damping ratio obtained by wind tunnel tests and quasi-steady theory is significant; wind-induced dynamic tensions of the transmission conductor under strong wind would be overestimated seriously without considering the aerodynamic damping.

关 键 词：风洞试验 气弹模型 气动阻尼 输电导线 风致响应 

分 类 号：TH212[机械工程—机械制造及自动化] TH213.3