考虑摆动效应的覆冰导线两自由度驰振稳定性分析

该文推导了考虑覆冰导线摆动的水平竖向耦合两自由度驰振模型,结合覆冰导线模型高频天平测力试验结果,采用劳斯判据分析了基于导线自振特性的广义两自由度准椭圆形覆冰导线的驰振稳定性。分析结果表明:在进行准椭圆形覆冰导线两自由度驰振稳定性分析时,气动力系数需采用七阶以上多项式描述;导线摆动对稳定性分析影响较大,不考虑导线摆动影响分析得到的不稳定风向角范围偏小,临界风速偏大;提高结构阻尼可以有效的提高驰振临界风速。最后得到了准椭圆形覆冰导线两自由度驰振稳定性分析的一般结论。

GALLOPING INSTABILITY OF TWO DEGREE OF FREEDOM OF ICED CONDUCTOR WITH SWING

A two-degree-of-freedom model for the coupled galloping of an iced conductor is developed in this paper.Using Routh-Hurwitz criterion,the galloping instability of a quasi-oval iced conductor,which have been tested in a wind tunnel by high frequency balance,is investigated on the basis of the new model.The research indicates that: the polynomial form with order higher than seven is sufficient of describing its aerodynamic force coefficients;the swing of the iced conductor has great influence on its stability,while the narrower range of galloping instability wind directions and higher critical wind velocity are obtained from the model without consideration of swing;structure damping plays significant roles in promoting critical wind velocity.These findings in the present paper provide the general characteristics of galloping instability for an quasi-oval iced conductor.