覆冰导线舞动的非线性数值仿真研究

Nonlinear numerical simulation study of iced conductor galloping

导线的覆冰舞动严重威胁特高压输电线路的安全运行。利用能考虑扭转自由度的的两节点索单元,并结合分裂导线等效为单根导线计算方法,建立了连续多档分裂导线舞动分析的有限元模型。同时采用计算流体动力学方法对覆冰导线气动特性进行数值模拟,获得了覆冰导线在各风攻角下的气动力系数。基于连续多档导线的有限元模型与气动力系数-风攻角曲线,利用龙格-库塔法对覆冰导线舞动进行非线性数值求解,并自编了FORTRAN程序。通过对汉江大跨越工程覆冰导线的舞动数值仿真分析表明,该方法与程序是可行的,且具有较高的计算效率;并利用该方法研究了风速与初始攻角对舞动的影响,为进一步研究输电线的舞动提供基础。

The galloping of iced conductors is a serious threat to the safety of transmission lines. A two-nodebar element having three translational and one torsional degree-of-freedom at each node was employed to model theconductor. Combining with the method of the bundle conductor equivalence to a single conductor, the finiteelement model of multi- span transmission line for galloping analysis was established. In addition, theaerodynamic coefficient of iced conductor under different wind attack angle was obtained by using eomputationahquid dynamics method. On the basis of the finite element model and aerodynamic coefficient curve, theRunge-Kutta method was applied to carried out nonlinear numerical simulation of iced conductor galloping andthe FORTRAN program was compiled. The galloping of the long-span transmission line crossing Hanjiang Riverwas analyzed. The results indicate that the presented method and program are reliable and efficient. Meanwhile, the impact of the wind velocity and initial attack angle on galloping were investigated with the program. They canprovide references for the further study of galloping.