汽车随机振动的建模与仿真

Modelling and simulation of full-vehicle random vibration

以整车九自由度模型为对象,用有限元思想将汽车振动结构离散。通过单元位移变换得到单元刚度阵和阻尼阵。按照单元位移在结构位移列阵中的位置组装汽车振动数学模型的系数矩阵。经过强迫位移约束处理,得到汽车振动数学模型。用有限元的思想求取振动响应量,应用虚拟激励理论实现汽车振动响应仿真。结果表明:建模与仿真相结合为复杂汽车随机振动分析提供了可行的方法。

Taking a 9 DoF full-vehicle model as an example,the vehicle vibration structure was discretized with the idea of finite element method（FEM）.The element stiffness matrix and damping matrix were given by the transform of element displacement.The coefficient matrix of the mathematical model of the vehicle vibration was assembled according to the position of the element displacement in the vector of structure displacements.A mathematical model of vehicle vibration was built as the forced displacement disposed of as the restraint.The vibration response variables were deduced with the idea of FEM,and their simulations were realized by the virtual excitation theory.The results show that the combination of the modelling and the simulation provides a practical approach to the random vibration analysis of complex vehicles.