高速列车驱动车轴动态特性分析

将车轮和轴箱分别简化为集中质量和转动惯量,用连续弹性Timoshenko梁模拟变截面车轴,建立弹性轮对与轨道耦合垂向动力学模型,分析车轴动态刚度与轮轨作用力、车轴自身振动特性和车轴动应力的相互关系。发现:轮对的一阶和二阶固有频率分别由76.34Hz和130.03Hz降低到53.68Hz和100.02Hz,车轴的一阶模态振动加速度和弹性振动位移分别增加60.12%和92.21%,轮轨动作用力增加6.23%,车轴轮座内侧和轴颈危险截面的动应力分别增加39.30%和34.13%。分析结果表明:轮轨动作用力和车轴的动应力随着车轴动刚度的降低而增加,因此,提高轻量化轮对的固有频率和动态刚度能保证高速列车安全运行和提高车轴疲劳强度。

Dynamic property analysis of axle shaft of high-speed train

Wheel and axle box were simplified to collective quality and inertia of moment,non-uniform axle shaft was simulated by using continuous elastic Timoshenko beam,an elastic wheelset/rail coupling vertical dynamics model was set up,and the relationships between the dynamic stiffness of axle shaft and wheel/track dynamic force,the vibratory characteristics and dynamic stress of axle shaft were analyzed.It is pointed that when the first natural frequency of wheelset reduces from 76.34 Hz to 53.68 Hz and the second natural frequency reduces from 130.03 Hz to 100.02 Hz,the first mode vibration acceleration and elastic vibration displacement of axle shaft increases by 60.12% and 92.91% respectively,wheel/track dynamic force increases by 6.23%,the dynamic stresses on the dangerous section inside wheel seat and on axle neck respectively increase by 39.30% and 34.13%.Analysis result shows that the dynamic force of wheelset and the dynamic stress of axle shaft increase with the dynamic stiffness decrease of axle shaft,so raising the dynamic stiffness of light wheelset can ensure the running safety of high-speed train and enhance the fatigue intensity of axle shaft.2 tabs,8 figs,10 refs.