角度风作用下多分裂导线的干扰效应和阻力系数

采用风洞试验方法研究角度风作用下多分裂导线的干扰效应和体型系数，对比不同风速和湍流度导线和同直径圆柱的阻力系数，获得不同风向角下多分裂导线的子线和整体的阻力系数，并与规范及他人结果进行对比. 研究表明，高风速下导线的阻力系数比光滑圆柱小13%，说明绞线外形可以减小圆柱的阻力系数；子线之间存在前后遮挡效应时后方子线的阻力系数显著减小，子线间距越小时阻力系数越小；存在显著干扰效应的风向角下多分裂导线的整体阻力系数较小；直径23.94 mm、间距400 mm的多分裂导线阻力系数包络建议值为：1.02（单导线和二分裂）、1.00（四分裂）、0.97（六分裂）、0.93（八分裂）.

Interference Effect and Drag Coefficients of Multi-bundled Conductors under Skewed Azimuths

Wind tunnel testing methods were employed to study the interference effect and drag coefficients of multi-bundled conductors under various azimuths. Drag coefficients of isolated conductor and circular cylinder with the same diameter were compared under various wind velocities and turbulence intensities. The drag coefficients of sub-conductor and total drag coefficients of multi-bundled conductor were obtained and their results are compared with those obtained from Codes and other researchers. The results show that the drag coefficient of the isolated conductor is 13% less than that of the circular cylinder under high velocity, indicating that the twisted shape can reduce the drag coefficient of the circular cylinder. When two sub-conductors are in front-back arrangement, the drag coefficient of the back sub-conductor decreases significantly, and the less distance between them, the more the drag coefficient decreases. The total drag coefficient of multi-bundled conductors is small under certain azimuth when the significant interference effect is considered. The enveloped drag coefficients of multi-bundled conductors with 23.94 mm in diameter and 400 mm in distance are recommended as 1.02, 1.00, 0.97 and 0.93 for isolated conductor, two-bundled conductor, four-bundled conductor, six-bundled conductor and eight-bundled conductor, respectively.