報告書番号

N09006

タイトル（和文）

着氷雪時の4導体送電線の各導体に作用する空気力特性

タイトル（英文）

Aerodynamic characteristics of each subconductor of ice and snow accreted four-bundled conductors

概要 （図表や脚注は「報告書全文」に掲載しております）

本研究では，着氷雪時の4導体送電線に作用する空気力の特性について議論するために，電線径・導体間隔などを実寸サイズで模擬した着氷雪送電線部分模型を製作し，風洞実験において単導体および4導体送電線の着氷雪時の空気力係数を計測した．素線によって表面に凹凸を有する送電線では，ギャロッピングが生じるような風速域で，着氷雪時の空気力係数が風速に依存し得ることを明らかにした．さらに，4導体送電線については，圧力測定実験により，導体ごとの空気力係数を計測し，風上側の導体の後流域の影響で，風下側導体の空気力係数の絶対値が低減することを明らかにした．また，その大きな一因として，後流域における流速の低下が考えられ，着氷雪単導体送電線まわりの平均流速分布を把握することにより，着氷雪単導体送電線の空気力から様々な電線径・導体間隔・導体数の着氷雪多導体送電線の空気力を推定することができる可能性を示した．

概要 （英文）

The present study is concerned with aerodynamic characteristics of four-bundled electric conductors of overhead transmission lines under ice and snow accretions, which may be used as input data for the galloping simulations of ice and snow accreted conductor lines. In this study, the aerodynamic coefficients of the single and four-bundled conductors were obtained with wind tunnel tests for five kinds of ice and snow accreted shapes by using sectional models of them. These tests were performed in variation with the wind speed. The results have shown that, because of surface roughness of the wire, aerodynamic coefficients of the ice and snow accreted conductors vary with the wind speed in the range where galloping could occur. Furthermore, to obtain the individual aerodynamic coefficients of each subconductor with the surface integration of the pressure, surface pressure measurement tests on the individual conductor models were performed in addition to three-component force balance tests. As a result, the aerodynamic coefficient of the downstream side conductor decreases due to the wake generated by the upstream conductor. Moreover, the aerodynamic coefficients of the ice and snow accreted multi-bundled conductors of overhead transmission lines will be probably estimated from those of a single conductor.

報告者

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