Dynamical modelling of wind-induced vibrations of overhead lines (Q796348)

A dynamical model is presented for the wind-induced vibrations of overhead lines due to Kármán vortex shedding. Because of the complexity of the excitation mechanism the model for the continuous structure is based on an appropriate nonlinear model of a circular rigid cylinder that is oscillating transversally in a flowing fluid. The exciting nonlinear forces acting on the cylinder are deduced from known experimental data. It is shown that the observed well-known ''lock-in''- effect can be described in satisfactory manner by this model. The transition from the rigid body model to the continuous, flexible structure leads to a nonlinear boundary value problem. Approximate solutions are derived by perturbation theory.