An investigation into the attenuation of wind speed by the use of windbreaks in the vicinity of overhead wires

Abstract

An experimental and computational analysis of the efficacy of windbreaks for the attenuation of wind speed in the vicinity of overhead wires is presented. This work has been specifically applied to the case of oscillation of overhead catenary contact wires in a cross-wind. A wind tunnel subscale model of a windbreak/overhead wire configuration is presented and discussed with regard to the feasibility of reducing the aerodynamically induced oscillations encountered in such situations. This porous blockage placed upstream of the simulated overhead wire attempts to represent the influence of a windbreak/shelterbelt on the reduction of the vibration phenomenon known as galloping. In conjunction with this experimental study, a computational fluid dynamics (CFD) analysis has been carried out in order to assess the influence of the shelterbelt on the catenary wires in a typical full-scale scenario. The results indicate that a dense shelterbelt of height H positioned between 2-8 tree heights, H, upstream of the suspended cables provides a sufficient reduction in wind speed to reduce significantly the amplitude of wire vibration.