大轴距轮式车辆动力学建模研究

Research on Dynamic Modeling of the Wheeled Vehicle of Large Wheelbase

对于大型载重车辆或轴距较大车辆,车架的柔性对整车振动特性的影响不容忽视。一般采用有限元法建立车架的柔体模型,但该模型规模大、求解效率低,不便于进行快速参数敏感度分析及结构优化。提出了运用多刚体离散元法快速建立车架有限自由度柔体模型的方法,所建模型可方便用于后续结构优化。以某混凝土搅拌运输车为例,建立了整车的动力学模型,并分析了其振动特性。通过对该车的振动测试,验证了所建模型的准确性及建模方法的有效性,为后续减振优化奠定了基础,可为类似结构车辆的动力学建模提供参考。

For large load vehicles or large wheelbase vehicles,frame flexibility on vibration characteristics of the vehicle can not be ignored.The dynamic modeling of the frame is usually carried out by finite element method,but the resulting model is often too large to be solved efficiently.In addition,the finite element model is inconvenient for rapid parametric sensitivity analysis and structural optimization.A new method is proposed to quickly generate the multi-degree-of-freedom flexible model of frame by using multi-rigid-body diserete element method.The resulting dynamic model can be easily used for structural optimization.The dynamic modeling of a concrete mixer truck is taken as case study to illustrate the procedure of the method,the vibration characteristic of which is analyzed.Vibration experiments of the vehicle under working condition verify the accuracy of the vehicle dynamic model and the effectiveness of the proposed method.The modal can lay the foundation for the follow-up damping and optimization,and can provide a reference for dynamic modeling of the similar vehicles.