轨道支撑刚度对轮扫掠力监测信号影响规律的分析研究

【作者】 柏友运；

【导师】 黄志辉；

【作者基本信息】 中南大学 ， 机械电子工程， 2010， 硕士

【摘要】 随着货车行驶速度的提高,货车的超偏载成为了引起货车脱轨等重大安全事故的主要因素。借助高速轨道车辆超偏载监测技术及时发现列车的超偏载现象,并采取必要措施避免恶性事故的发生具有十分重要的意义。为研究超偏载监测技术,设计制造了高速轮扫掠力检测实验台,以期在发掘轮轨扫掠力的作用关系前提下,去深入研究该技术。本文针对实验台中轨下支撑条件变化对扫掠力监测信号的影响展开研究,借助有限元分析软件建立柔性支撑条件下的轮轨滚动接触有限元模型；运用正交设计法合理安排仿真组合并进行动力学仿真,找出其影响规律；同时结合实验研究,验证该数学模型的正确性,完善了轮扫掠力监测技术的研究理论与体系。论文主要研究内容如下：(1)对国内外轨道动力学模型的研究进行了综述,针对本研究内容的特殊性,采用有限元方法进行建模,并从理论上详细阐述了有限元的分析方法及显式动力有限元程序LS-DYNA的算法基础。(2)以轮扫掠力监测试验台为研究对象,运用大型有限元分析软件ANSYS／LS-DYNA,通过对单元类型、材料模型、接触算法的选择以及载荷、边界条件的施加建立轨道的有限元模型；利用非线性显式动力有限元程序LS-DYNA进行轮轨滚动接触的计算求解,实现其动力学仿真。(3)运用正交试验设计法,选取轮载、支撑刚度和速度为三种变量因素,以钢轨指定点的应变值为试验指标,合理安排仿真试验,利用后处理软件LS-PREPOST提取仿真结果；根据传感器工作原理,将结果曲线中的应变输出量转换为实际中的检测电压信号,总结了包括轨下支撑刚度在内的三种变量因素对扫掠力监测信号的影响规律。(4)设计制造完成一套能实现不同装载重量通过钢轨检测区并能改变轨下支撑刚度的设备并在此实验台上进行静态实验；采集实验数据并与仿真结果类比,验证了仿真模型的正确性,为下一步采用更精确的模型进行仿真提供了可行的研究方法。更多还原

【Abstract】 With the increase in freight train speed, the overload and unbalanced-load of the train becomes the major factor of the running accident that the freight train derailed and turned over. By the technology of overload and unbalanced-load measurement to detect overload and imbalanced load in time, take necessary measurements to avoid running accidents, which possesses much significance. To further study the overload and unbalanced-load measuring technology, a small-scale experimental platform for the high speed wheel-scan force detecting was designed and built. The thesis studied the affect of the wheel-scan force detecting signals when the support conditions under the rail changed. The wheel/track contact model under flexible support was established in finite element analysis software; By the orthogonal experimental design method, the Simulate combination was rationalized, and the dynamic simulation was done; Combined with experimental research, the correctness of this mathematical model was verified and it improved the initial integration of wheel-scan force detecting system.The main contents are detailed as following:(1) The track dynamic model in domestic and overseas was summarized. Directed towards the specificity of this study’s content, the finite element method was used to model, and the arithmetic theory and process of the analysis problem by explicit dynamics finite element analysis procedure LS-DYNA was theoretically expatiated。(2) The finite element model of rail was established in the large finite element analysis software "ANSYS/LS-DYNA" by selecting of element type, material model and contact algorithm, etc. the explicit nonlinear dynamic finite element procedure "LS-DYNA" was used to solve and the dynamic simulation was carried out.(3) By the orthogonal experimental design method, the wheel load、brace stiffness and velocity was chose as variable factors, the strain value of the designated point on the rail as test indexes. After the simulation test, the simulation results were got by the post-processing software "LS-PREPOST". According to the working principle of the sensor, the strain output in the result curves was changed to the practical detecting voltage signals, and the impact of these three variable factors on the wheel-scan force detecting signals was summarized.(4) A set of equipments which can achieve different loaded weight through the rail detection area and change the brace stiffness under the rail was designed and manufactured and static experiment was executed. Compared the experimental datas with the simulation results, the similarities and differences were get and the reason was analyzed. The model’s correctness was proved, which provide feasible research methods to next simulation.更多还原