Investigation On The Model Experiment Of Iced Conductor Galloping

Iced conductor produces the galloping phenomenon when it is influenced by the external wind excitation.Conductor galloping phenomena have complex performance and multiple variables.However,study on wind-induced vibration of iced conductors is mainly concentrated on the theoretical derivation.Experiment research mostly focused on the section model of the gas dynamic parameters measurement.It is hard to reveal the characteristics of iced conductor galloping system through this way.The study on the similarity analysis of dynamic model of iced conductor wind-induced vibration system has not been fully completed.Study on conductor galloping behavior in different wind speed by using continuum model and similar method is rare.A model research method based on similarity theory for iced conductor galloping has been put forward in this paper.Extracting the key parameters from complex formulas based on dimensional analysis method and a formula analysis method.Calculated some important similarity ratios contain system dynamic coefficient and initial conditions based on distortion model theory.The similarity principle of the iced conductor system between model and prototype has been declared.Through the contrastive demonstrate between mathematical model and numerical calculation result,the paper discussed the dynamic characteristic parameters and the dynamic response of the wind stimulation of iced conductor's wind-induced vibration system.The wind tunnel especially for the galloping experiment of continuous iced transmission line is established.The detailed test packet and the speed of packet planning are designed.And laser sensor is adopted to measure the dynamic displacement at different spans of the model,according to which the galloping profile are obtained under different wind velocity.The first three modal as well as the single modal galloping,the two modals and the multi-modal coupling galloping behavior of the system are simulated.The concrete rules and the influences of the initial tension on the system under wind speed change are revealed.Model test study on iced conductor system can broaden the scope of the study on model test and also develops and improves the iced conductor dynamic similarity theory.This study can be seen as a guidance of iced conductor dynamic model test theoretical.It reflects the system of the wind speed change of galloping behavior and supports the theory of iced covered,mutual confirmation.It is a successful attempt in the field of similar model test of iced conductor,which lays a basic foundation for next research on the galloping behavior of iced conductors.