线路不平顺对轮对纵向振动的影响

在常规的机车车辆动力学仿真中，通常不考虑轮对的纵向自由度，可以说轮对纵向振动问题是一个长期以来被忽略的内容．本文的研究发现轮对纵向振动虽然对整车的横向稳定性影响不大。但却对整车的垂向动力学有很大的影响．当轮对纵向振动较大时，会导致机车发生纵向伴随点头的振动，恶化机车的垂向动力学性能．进一步的分析发现，剧烈的轮对纵向振动与轨道的垂向和水平不平顺关系密切．同时存在这两个不平顺是产生轮对纵向共振的前提，在光滑的轨道上不会有纵向共振发生．

Influence of track irregularity to wheel set longitudinal vibration

The wheel set longitudinal degree of freedom of movement was ignored in the general dynamic simulation analysis of railway vehicles. We can say that wheel set longitudinal vibration hasbeen ignored by researchers for a long time, But in recent research, we find that although the acute vibration in longitudinal of the wheel set has a little influence on the lateral stability of the whole vehicle, it has a big influence on the vertical dynamic performance of the whole vehicle. The longitudinal and nodding vibration of the car body will occurr and even lead the vertical dynamic to worsen when there is a big wheel set longitudinal vibration. Farther research finds that the wheel set longitudinal vibrate is heavily related with the track vertical profile track irregularity and lateral track irregularity. Only when the above two track irregularities were exited together, the wheel set longitudinal vibration resonance couldn＇t happen. Wheel set longitudinal vibration resonance on the slick track will not occur.