农用车辆橡胶隔振元件动力学模型研究

Research on dynamic model of rubber vibration isolation component for an agricultural vehicle

以某农用车辆发动机前悬置软垫为研究载体,研究橡胶隔振元件的动力学建模、参数辨识以及数值求解方法。首先通过动态加载试验分析发动机前悬置软垫动态特性的频率响应特性与幅值响应特性,建立一种弹性单元、摩擦单元和高阶分数导数粘弹性单元叠加的橡胶隔振元件动力学模型;然后提出基于广义多维学习策略和自适应调整策略的粒子群算法的粘弹性单元参数辨识方法,结合试验结果,辨识得到模型参数;最后推导高阶分数导数粘弹性单元的数值求解方法,将其运用于所建模型的求解。经试验验证,建立的模型能够精确地预测橡胶隔振元件的动态特性,在不同振幅和频率工况下,模型计算与试验得到动刚度的平均误差和最大误差分别为3.08%和4.52%,阻尼系数的平均误差和最大误差分别为4.58%和5.79%,对提高农用车辆各系统及整车动力学仿真精度有一定的意义。

The dynamic modeling,parameter identification and numerical solution methods of rubber vibration isolation components for agricultural vehicles were studied.Firstly,the frequency response characteristics and amplitude response characteristics of the engine front mount cushion were analyzed through dynamic loading test.A dynamic model of rubber vibration isolation component with elastic element,friction element,and high-order derivative viscoelastic element was established.Then a viscoelastic element parameter identification method based on generalized multidimensional learning strategy and adaptive adjustment strategy was proposed.Finally,the numerical solution method of higher order fractional derivative viscoelastic component was derived and applied to the solution of the established dynamic model.Test results verified that the established model could accurately predict the dynamic characteristics of rubber vibration isolation component.Under different amplitude and frequency conditions,the average and maximum errors of dynamic stiffness calculated by the model and test were 3.08%and 4.52%,respectively,and the average and maximum errors of damping coefficient calculated by the model and test were 4.58%and 5.79%,respectively.This is of great significance to improving the dynamics simulation accuracy of the agricultural vehicle.