基于弯扭轴综合振动混合模型的汽车传动系复模态分析及仿真研究

Complex Mode Analysis and Simulation Research of Automotive Driveline Based on Bending-torsional-axial Coupled Vibration Hybrid Model

基于系统动力学与结构动力学相结合的建模思想,介绍汽车传动系扭转、弯曲、轴向综合振动混合模型的建模特点,并从轴类部件的结构动力学建模、斜齿轮副、轴承和轴系附属质量(惯量)的系统动力学建模和基于坐标变换的部件间联接三个方面,对汽车传动系扭转、弯曲、轴向综合振动混合模型的建模方法进行探讨,在该模型的基础上对传动系进行复模态分析,发现混合模型计算的前4阶模态的主要振动形式为扭振,且与系统动力学分支扭振模型计算的前4阶结果相差不大,从第5阶模态之后都是两种或三种振动形式的耦合;以起步颤振为对象进行仿真研究,发现传动系混合模型的仿真结果较分支扭振模型在颤振程度上稍有增强且特征频率近似相等,说明弯曲和轴向振动对起步颤振现象影响不大。

The characteristics of torsional-bending-axial coupled vibration hybrid model for automotive driveline are introduced based on the combination of system dynamics and structural dynamics and the modelling methods of hybrid model for automotive driveline are also discussed from three aspects which are structural dynamic modelling of shaft, system dynamic modelling of helical gear pair, bearing and attaching mass（inertia）, connections among components by coordinate transformation. Complex mode analysis of driveline is analyzed and it is found that the main vibration mode of first four order modal calculated by hybrid model are torsional vibration and they are similar to the first four order modal calculated by system dynamic branched torsional vibration model, the main vibration modes are two or three forms of coupled vibration after the fifth order modal. It is discovered that the shudder degree of hybrid model is slightly enhanced and the characteristic frequency is almost the same between hybrid model and branched torsional model from the simulation research of launch shudder. It is also concluded that bending and axial vibrations have little effect on launch shudder phenomenon.