基于混合子结构法的输电导线风雨激振气动特性

Hybrid Substructure Approach for the Investigation on Aerodynamic Characteristics of Rain-Wind Induced Vibration on Transmission Line

为了探究输电导线风雨激振的诱发机理,基于混合子结构方法对输电导线风雨激振非定常气动力进行了针对性的研究。首先,分别构建结构子结构(输电导线和上雨线)和流体动力计算(computational fluid dynamics,简称CFD)数值流场子结构;其次,利用自制的风洞模拟实验台及相关测试系统,获取结构子结构的振动响应(频率,振幅);最后,将测得振动响应作为CFD数值模拟的边界条件,计算绕流场特性并获取气动力特性参数,将计算得到的气动力施加到输电导线上,得到输电导线的振动响应并与实验结果比较。分析结果表明,混合子结构方法能够准确获得输电导线发生风雨激振时的气动特性,该方法为不便于实验获取气动力特性振动问题研究提供了一种有效途径。

Under rain-wind conditions,rivulets often form on the surface of transmission lines,which may cause the rain-wind induced vibration.This kind of vibration seriously threats the safety and stability of the transmission tower-line system.The rivulet′s effect on the original cross-section formation of the transmission lines and its movement are likely to be the cause of the aerodynamic instability.To analyze the mechanism of rain-wind induced vibration on transmission,the transient aerodynamic characteristics of rain-wind induced vibration on transmission line is studied based on the hybrid substructure approach in this paper.The transmission line(including the rivulet)and the flow field are considered as two substructures;the vibration response of the transmission line is measured through wind tunnel tests treated as the moving boundary condition of transmission line in the flow field.Only the flow field around the moving boundary is simulated by the computational fluid dynamics code to obtain the aerodynamic characteristics of rain-wind induced vibration on transmission line.Lastly,the transient aerodynamic lift and drag coefficients are applied to the transmission line,and the comparison is carried out between the vibration responses of the transmission line and experimental results.The research results show that the hybrid substructure approach is an effective approach to obtain the transient aerodynamic characteristics of rain-wind induced vibration on transmission line,and also provides an effective method to obtain aerodynamic characteristics which are inconvenient to be measured in the tests.