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Due to the influence of the land roughness, the lower the wind load, the higher turbulence intensity of wind. According to wind tunnel tests, it can be found that the aerodynamic coefficients of iced 8-bundled conductor are significantly different under different turbulence conditions, and the Den Hartog and Nigol coefficients determined by aerodynamic coefficients are also different. Based on the test results, the numerical analysis of the galloping of iced 8-bundled conductor is analyzed, and the response of galloping to the change of turbulence is investigated. The mathematical simulation results of galloping traces show that the galloping amplitudes of the iced conductors and the range of initial attack angle increase obviously under turbulence conditions. Moreover, the effects of different parameters on the galloping of iced 8-bundled conductors are researched. The parameters such as wind velocity, attack angle, and span length on the galloping of the 8-bundled conductors under turbulence wind loads are obtained by numerical method, which offers a theoretical basis for the study of the technique of anti-galloping. [ABSTRACT FROM AUTHOR]

Wake-induced galloping is a high risk for a safe operation of electrical transmission system due to dense arrangement of sub-conductors in multi-bundle conductors. To investigate the wake-induced galloping characteristics of eight bundle conductors with extra-high voltage, the variation of aerodynamic forces of each sub-conductor in the eight bundle conductors changing with angle of attack was tested by wind tunnel tests. Because of the wake interaction within subconductors, a relatively distinguishable difference can be observed among the aerodynamic forces of the eight conductors. Especially, when a leeward sub-conductor is in the wake of windward sub-conductor, the drag exerted on the leeward conductor significantly drops. The wake-induced galloping of eight bundle conductors with two span-lengths 308 m and 405 m was numerically simulated by the ABAQUS software. Based on the simulation results, a critical wind speed has been found for the wake-induced galloping. The galloping will not take place when the wind speed is lower than the critical speed. The motion orbit of the sub-conductor is elliptical with wake-induced galloping. Given the same wind speed, the amplitude of the galloping with long span-length is greater than that with short span-length. [ABSTRACT FROM AUTHOR]