Dynamic Response of a Two-Conductor Bundle to Eolian Excitation

This paper describes the required formulations and the various stages involved in calculating the dynamic response of a two-conductor bundle equipped with flexible articulated spacers to eolian excitation generated by the wind on a conductor by the alternative lift forces as a result of so-called Von Karman vortices. The formulations take into account both the damping that exists in the conductors and spacers and the inertial characteristics of the latter.The analytical model developed, which is based on the transfer matrix method, allows the following parameters to be calculated for each eigenvalue of the matrix of the generalized stiffness of the spacer: the resonance frequencies of the bundle and corresponding characteristic distribution, the eolian power induced in the conductors and dissipated in the latter and in the spacers, for each vibration mode of the system, and the equilibrium amplitudes along the span length for which the power induced in the system is equal to that dissipated.The formulations developed during the course of this work were computerized and applied to the case of a two-conductor bundle. The results of these calculations are presented.