钢轨打磨对动车组运行性能的影响

在广深线部分大半径曲线区段和直线区段,钢轨内侧存在明显的侧磨,且动车组水平加速度频繁超限。通过对钢轨侧磨区段发生异常晃动车体的前后端、左右侧加速度进行测试,结合侧磨区段钢轨廓形的测量结果,可以判断出在该型动车组频繁水平加速度超限区段存在不良轮轨接触关系。采用SIMPACK动力学分析软件建立该型动车组单轮对、转向架、整车的动力学模型,分析了自由轮对仿真模型和弹性定位、完全刚性定位转向架仿真模型采用广深线打磨前后实测钢轨踏面时蛇行频率与车体固有频率的仿真结果。分析结果表明:当动车组以160 km/h左右速度运行在打磨前实测廓形区段时,转向架蛇行频率与车体横向固有频率相同,造成车体平稳性和舒适性严重恶化;钢轨廓形打磨以后,改善了轮轨匹配关系,车载仪超限数量、添乘仪报警个数、轨检指标较打磨前均得到明显改善。

Influence of Rail Profile Grinding on Running Performance of EMU

In the big radius curve section and straight section of Guangzhou-Shenzhen railway,there is obvious side wear on the inner side of the rail,and the horizontal acceleration of the EMU frequently exceeds the limit.The accelerations of the front and rear parts and the left and right sides of the vehicle body which abnormally shaking were tested,and rail prof iles in side wear section were measured.From the results it can be judged that there is undesirable wheel-rail contact relationship in the section where the horizontal acceleration of the EMU frequently exceeds the limit.The dynamic model of single wheelset,bogie and whole vehicle of the type of EMU was established by using SIMPACK dynamics software.The simulation results of the hunting frequency and the natural frequency of the free wheelset simulation model,the elastic positioning bogie simulation model and full rigid positioning bogie simulation model which adopted measured rail prof iles before and after grinding were analyzed.The analysis results show that when the EMU passed through measured rail prof iles section before grinding,the hunting frequency of the bogie coincides with the natural frequency of the vehicle,resulting in serious deterioration of vehicle stability and comfort.After grinding the rail prof ile ,the wheel-rail matching relationship is improved,and the number of onboard instrument exceeding the limit,the alarm number of the multiplying instrument and the track quality index were obviously improved compared with those before grinding.