Numerical Simulation Analysis Of The Aerodynamic Characteristics Of Overhead Conductors

Overhead conductor usually generates a breeze vibration, dancing and subspan vibration under the action of wind loads. Wind-induced vibration is one of the main factors that endanger the safe operation. In the analysis of wind-induced vibration of the conductor, the unsteady aerodynamics are related to the flow separation and the generation of the vortex and have strong nonlinear characteristics, so it is difficult to use simple theory or some analytical formula to describe the unsteady aerodynamic characteristics due to various actual conductor and the diversity and complexity of the iced conductor. The aerodynamic characteristics of the conductor are simulated through the fluid dynamics software(CFD), which provides a theoretical basis for the further development of wind-induced vibration, the paper's main contents are:Firstly, the aerodynamic parameters of crescent iced conductor are calculated under different wind speeds, angle of attack and ice thickness, the calculation results show:(1) the aerodynamic parameters of the different conditions are different, but they are almost the same with the change of the angle of attack.(2) The wind speeds and ice thickness have an effect on the three component coefficients, but the rule and the degree of effect is different. Finally, the fitting function of the three component coefficients changed with the angle of attack is obtained by using the three spine-function and carries on the error analysis.Secondly, overhead conductor is simplified into a single degree of freedom vibration model, a numerical calculation method of wind-induced vibration of a rigid cylinder under an elastic support is used to simulate the wind-induced vibration of a cylinder at low Reynolds number, the calculation results show: the vortex induced vibration is the limiting vibration, and the amplitude decreases with the increase of damping. As increase of the wind speeds, the amplitude increases first and then decreases. The conductor resonates when the vortex frequency is close to the natural frequency of the conductor.