接触网三维模型的建立与风偏的非线性求解

Establishment of 3D Model for Catenary and Nonlinear Solution for Its Wind Deflection

本文利用空间梁单元与柔性索单元离散电气化铁路接触网,考虑梁单元变形时的几何非线性,采用动坐标迭代法进行求解,计算平衡状态下的吊弦长度,建立接触网三维力学模型。分别利用流体力学软件和风洞试验计算接触线截面的气动力系数,并将横风载荷施加到此模型中,研究风速、张力等因素对接触线风偏的影响,以及考虑几何非线性在研究接触网较大位移问题时的必要性。研究结果表明:在求解接触网大位移问题时,不考虑梁单元变形产生的几何非线性,会对结果造成一定的误差。本文仿真结果可为接触网防风设计提供有益借鉴,提出的仿真方法可适用于接触网发生较大位移时的精确计算,也为研究更为复杂的接触网三维力学特性提供条件。

In this paper ,the spatial beam element and flexible cable element were adopted to disperse the cate‐nary of electrified railway .Based on geometric nonlinearity caused by the deformation of beam element ,and through the use of the moving coordinate iterative method to improve the solution procedure ,the lengths of the droppers under the equilibrium state were calculated and accurate 3D mechanical model for the catenary was es‐tablished .The aerodynamic coefficients of contact wire section were calculated through the CFD software and wind tunnel experiment ,respectively .With the cross‐wind loads being applied to the model ,the influence of wind speed ,tension and other factors on the wind deflection of the catenary was studied and the necessity of considering geometric nonlinearity in studying large displacement problem of the catenary was evaluated .The results implied that the neglection of geometric nonlinearity caused by the deformation of beam element would cause some errors on the results when the large displacement problem of the catenary was being solved .The simulation results can provide a useful reference for the wind‐resistant design for the catenary .The proposed simulation method may apply to precise calculation of large displacement of the catenaryand provide conditions for the study of more complicated 3D mechanical characteristics of the catenary .