动车组车辆地板振动问题及其优化

针对某型动车组高速运行时地板振动脚感发麻问题,对该车进行了线路运行试验.通过振动传递分析与运行舒适度分析发现,车体钢结构振动经弹性支撑元件传递至地板后,在20~50Hz频率范围的振动被放大,且该频率范围覆盖了人体腿部敏感频率,导致乘坐时脚感发麻.为进一步研究地板振动放大机理,建立了包含地板的车体精细化有限元模型,并对模型进行验证.有限元分析结果表明,原地板弹性支撑刚度参数不当,导致地板局部模态频率与车体钢结构局部模态频率接近,进而导致地板与车体底架发生局部共振现象,地板振动能量被放大.针对地板弹性支撑参数不当进行了优化研究,并对优化方案进行了试验验证.试验结果表明,优化设计有效地解决了地板振动发麻问题.

Vibration Issue and Its Optimization of the Floor Structure in Electric Multiple Unit Trains

For the problem of the vibration on the floor structure in a railway vehicle when running at a high speed, in-situ tests are carried out. Vibration transmission analysis and ride comfort analysis show that the vibration transfers from the steel structure to the floor structure is amplified in the frequency range from 20 Hz to 50 Hz, which is the sensitive frequency range that covers the human legs. To study the floor vibration amplification mechanism, a finite element model of the railway vehicle car body which includes the floor structure is established and verified. The results of the finite element analysis show that due to the improper stiffness of the original elastic support components, the frequencies of the eigenmodes of the floor structure close to those of the steel structure, which leads to the resonance phenomenon between them, then the floor vibration energy is enlarged. Finally, the optimization of the elastic support stiffness parameters is studied and verified by the test. The test results show that the optimized design effectively solves the vibration problem of the floor structure.