高速列车车轮多边形化对车辆动力学性能的影响

采用车轮圆周轮廓法建立比传统等效轨道激扰法更准确的车轮多边形化模型,假设车轮型面不发生变化,车轮半径沿圆周方向发生改变.只考虑车轮周期性多边形不圆顺,且同一轮对上的2个多边形车轮不存在幅值和相位的差异,建立车辆-轨道耦合系统动力学模型,计算高速运营状态下周期性多边形的车轮振动响应、轮轨垂向力等动力学指标.结果表明:车轮多边形化会使车体振动响应增大,影响乘坐舒适性;车轮多边形化还会引起较大的轮轨垂向力,甚至当不圆顺幅值为0.5mm时,会出现轮轨相互瞬时脱离的现象,且同等条件下幅值对车辆系统动力学性能的影响比谐波阶数更为显著;针对高速列车车轮多边形化的动态特征,提出轮轨垂向力来划定其安全区域.在京津实测线路上,得到不同车速下,1、2、3和4阶车轮多边形化的幅值限制值分别为1.0、0.4、0.4和0.3mm.

Effect of Polygonal Wheel on Vehicle Dynamic Performance

Based on the assumption that the shape of wheel profile is unchanged and only the wheel out-of-roundness (OOR) changes,which is more accurate than the model of equivalent track excitations,the polygonal wheels were simulated by programming.Then,the coupled model incorporating the vehicle-track system dynamics was set up.The dynamic performance of ideal wheel and polygon wheel under high-speed running were simulated and the critical range of the wheel out of roundness was determined.The simulation results showed that the wheel OOR will increase the carbody responses and affect the passenger ride comfort,and result in large wheel-rail vertical forces,which is more strongly related to the OOR order than amplitude and vehicle running speed.The safety limits for 1, 2, 3 and 4 order polygon are 1.0,0.4,0.4 and 0.3 mm.