覆冰导线气弹模型舞动风洞试验研究

摘要

Single and bundled iced-conductor aeroelastic models were fabricated for two typical ice coating D-shape and crescent-shape sections.The vertical to rotational mode frequency ratio of the aeroelastic model can be changed by varying spring stiffness,suspension position and additional weight.After adjusting the ratio of vertical to rotational mode frequency,wind speed and attack angle,galloping of single D section iced-conductor,two-bundled and four-bundled crescent section iced-conductors were excited in the wind tunnel.Galloping of single D section iced-conductor can be generated whether the vertical and rotational self-vibration frequency is close or not.However,galloping of two-bundled and four-bundled crescent section iced-conductors requires close vertical and rotational frequency.Results from the wind tunnel test indicate that the ratio of vertical to rotational self-vibration frequency significantly affects the stability of galloping.Single conductor and bundled conductors with identical ice coating shape exhibit different galloping stability characteristics.It is also found that rotational response of the conductor has an important impact on the excitation and the vertical response value of galloping.%制作了D形和新月形两种典型覆冰断面的单根及分裂覆冰输电导线气弹模型,通过调整导线模型的弹簧刚度、悬挂点位置和配重质量获得不同竖向/扭转自振频率比,并调整风攻角和风速,在风洞中激发并记录D型单根覆冰导线和新月形二分裂、四分裂覆冰导线的舞动现象。D型单根覆冰导线在竖向/扭转自振频率比接近和远离时均能观察到舞动现象;而新月形二分裂、四分裂覆冰导线只在竖向/扭转自振频率比接近时发生舞动。试验结果表明：竖向/扭转自振频率比将影响导线舞动稳定性,相同覆冰断面的分裂导线与单根导线表现出不同的舞动稳定性特征,导线扭转响应对导线舞动的产生及舞动过程中的竖向运动响应均有较大影响。