为了降低车体的弹性振动,将车体考虑为两端自由等截面欧拉梁,建立了铁道客车刚柔耦合系统垂向动力学模型,通过幅频特性分析计算了系统各部件固有模态以及车体模态损耗因子对车体弹性振动的影响。对车体表面局部进行约束阻尼处理,通过合理假设推导了含有约束阻尼层的车体模态损耗因子的计算公式。数值分析结果表明:车体一阶弯曲自振频率接近人体振动敏感区域,为减小车体弹性振动,必须首先降低一阶弯曲振动。良好的乘坐舒适性可以通过增加车体结构的损耗因子来实现,车体局部贴附约束阻尼层可以增加车体结构阻尼。为了使车体结构获得最大的损耗因子,阻尼材料应该贴附在弯曲变形最大的位置,并且约束层和粘弹性层贴附长度和厚度有一个最佳值。只要选择合适的阻尼材料,就能获得很好的减振效果,从而达到提高高速客车乘坐舒适性的目的。
In order to reduce car body elastic vibration, a mathematical model of the vertical vibration for high-speed railway passenger car based on rigid-flexible coupling system was established, in which car body was modelled as a simple uniform elastic Euler beam with free ends. Based on the amplitude-frequency characteristic analysis, the natural frequencies of vehicle system's components and the effect of loss factors on car body elastic vibration were researched. Constrained damping layers were partially pasted on the outside sheathing of car body, and the formulae of modal loss factors were derived through reasonable assumptions. Numerical calculation result illustrates that the first bending vibration mode of car body occurs near the frequency region where riding comfort is most affected. Consequently, it is important to suppress the vibration firstly. Good riding comfort can be achieved by increasing the loss factors of car body. Constrained damping layers treatment can increase car body structure's loss factors. In order to obtain the maximum loss factors, constrained damping layers should be struck on the place with largest car body flexural deformation, and there exists optimum length and thickness of every damping layer. Good damping effect of the vibration and good riding comfort of high-speed railway passenger car can be obtained by choosing appropriate characteristics of damping layers. 2 tabs, 11 figs, 12 refs.