垭口型微地形对输电线路风载荷影响的分析

Effects of yakou micro-relief on the wind loading formulation for transmission line design

风载荷是输电线路设计及运行中需要考虑的重要载荷,输电线路在跨越垭口微地形时风速得到显著提高,风载荷加大。采用ANSYS/FLOTRAN CFD软件对输电线路跨越垭口微地形的空气动力学过程进行数值计算,建立了以垭口微地形的地形参数为基础的数学模型,给出了风载荷的分布规律,并用数学公式拟合,确定了垭口微地形所引起的风载荷的修正系数。通过与现行荷载规范进行分析比较,说明了垭口微地形条件下风速的拟合公式具有更高的精确性,为输电线路的铁塔设计及安全性评价提供了可靠的理论依据。

Wind load is an important load in design and operation of transmission line. The wind load obviously increase when transmission line crossing yakou micro-relief. In this paper, numerical calculation of aerodynamic process that transmission line crossing yakou micro-relief was carried out by ANSYS/FLOTRAN CFD software. Numerical model based on the parameters of yakou micro-relief was built and the distributing rule of wind velocity was given. Furthermore, the correctional coefficients of wind velocity caused micro-relief were established through fitting of the mathematics formula. Compared the coefficients with the result given by existing load criterion, it is clear that the fitting formula of wind given is more precise which can provide a reliable theoretic basis to design of tower and safety assessment of transmission line.