车轮滚过钢轨错牙接头处产生的轮轨冲击噪声机理分析

Generation mechanism of wheel /rail impact noise due to a train wheel passing through rail joints with height difference

当列车通过钢轨错牙接头时,会产生强烈的冲击并引起冲击噪声。为了探明铁路线上列车通过钢轨错牙接头处产生的轮轨冲击噪声,建立了基于车轮-轨道相互作用的轮轨冲击噪声预测模型,计算分析了钢轨错牙接头激扰下轮轨冲击力和冲击噪声的特性。结果表明:车轮通过钢轨错牙接头时会产生剧烈的冲击力和冲击噪声;迎轮错牙引起的轮轨冲击力峰值比送轮错牙接头要大210.5 kN,而引起的冲击噪声比送轮错牙接头大10～20 dB(A)。错牙高度越大其引起的轮轨冲击力和轮轨冲击噪声也越大。钢轨错牙高度增加0.5 mm时,轮轨冲击力最大峰值约增大60～90 kN,而轮轨冲击噪声在全频段都会增加1～3 dB(A),钢轨错牙引起的轮轨冲击力与冲击噪声成正比关系。随着车轮运行速度的增加,其激发的轮轨冲击力相应地增加,P1力变化比P2力明显,车轮速度在100 km/h以上钢轨错牙引起的轮轨冲击噪声变化十分显著。

When a train passes through rail joints with height difference in a railway line, impact forces and impact noises can be produced seriously. In order to predict and control the wheel/rail impact noise, a model simulating wheel/rail impact noise was presented based on vehicle-track coupled interaction. The wheel/rail impact forces and noises due to a train wheel passing through rail joints were studied. The results showed that wheel/rail impact force and impact noise dramatically produce when a wheel passes through rail joints with height difference; peak value of wheel/rail impact force due to passing upward height difference of rail joint was 210.5 kN more than that due to passing downward height difference of rail joint, whereas wheel/rail impact noise due to passing upward height difference of rail joint has 10-20 dB(A) more than that due to passing downward height difference of rail joints; the more the height difference the more the impact forces and impact noises; the height difference of rail joint increases 0.5 mm, then the maximum peak of wheel/rail impact increases about 60-90 kN, whereas the wheel/rail impact noise in a fult frequency band increases 1-3 dB (A); the wheel/rail impact force is proportional to the wheel/rail impact noise; with increase in wheel running speed, the wheel/rail impact forces due to rail joints with height difference increases; force P1 varies more obviously than force P2 does; when a wheel speed is above 100 km/h, the wheel/rail impact noise due to rail joints with height difference changes sharply.