输电塔线体系风洞试验模型的变比例问题分析

Analysis of the distorted scaling factor in wind tunnel modeling of power transmission line system

塔线体系的气弹模型风洞试验时,由于模型制作和现有风洞尺寸条件的限制,输电塔线体系中塔与线保持相同比例的气弹模型制作难度很大,往往需要将导线跨度的比例缩小。从数值分析的角度出发,以某1 000 kV双回路线路的一段塔线体系为例,铁塔保持不变,导线的缩聚比例分别为1.00、0.50、0.25的情况进行顺风向的风振响应时程分析。结果显示,导线比例缩聚后,塔线体系的风振响应基本保持一致,缩聚模型的风洞试验结果可以比较准确的反映原型的风振响应。

Because of the limitation of the model making and the existing wind tunnel＇s size, it is difficult to keep the line and tower in the same scaling factor in developing the aeroelastic model of the power transmission lines system, and a distorted sealing factor is needed in span length of the lines. With the instance of a 1 000 kV two-circuit power transmission lines, the finite element analysis under the alongwind load in time history is conducted with keeping the tower in the same and the line scaling factor being 1, 0.5 and 0.25 respectively. The results show that the response of the power transmission lines systems keep in the same, and then the wind-induced vibration of the distorted model in the wind tunnel test can actually reflect the response of the power transmission lines system under the wind load.