基于ANSYS的多轴汽车振动响应分析

为了高效预测路面不平度输入下多轴汽车悬挂质量某一位置处的振动响应特性，依据多体动力学理论，利用ANSYS仿真工具建立多轴汽车的七自由度动力学仿真模型。在整车发动机定转速的试验基础上，运用理论分析、仿真计算相结合的方法，根据建立的模型对整车进行仿真分析与研究。结果表明仿真计算结果与试验结果基本一致，可见，所提出的动力学模型和分析方法具有较好的可信度。仿真结果表明：在路面不平度输入下，影响悬挂质量-]6 m～-]4 m处的加速度响应以第1阶固有频率为主；而在-]2 m～4 m处以第2阶固有频率为主，尤其是在悬挂质量的后端；第2阶固有频率是影响多轴汽车加速度振动响应特性的最主要的因素，改善该多轴汽车的平顺性需把研究重点放在多轴汽车的第三四车轴的悬架系统上。

Analysis of Vibration Response of Multi-axle Vehicle Based on ANSYS

In order to efficiently predict the vibration response characteristics of sprung-mass in some locations of a multi-axle vehicle at the prescribed speed with the input of road roughness, a 7-DOF dynamic simulation model was established by means of ANSYS according to multi-body dynamics principle. Based on the vehicle＇ s engine test with the prescribed rotary speed and theoretical analysis, simulation of the vehicle was made with the established model. It showed that the results of simulation agreed well with the test. Therefore, the proposed dynamics model and method are reliable. Simulation results showed that the vibration response characteristics of sprung mass at - 6 m - 4 m locations are mainly influenced by the first order natural frequency and at - 2m--4 m locations mainly affected by the second order natural frequency. Especially at the rear end of the sprung mass, the second order natural frequency is the most important factor that impacts the acceleration vibration response characteristics of the multi-axle vehicle. Therefore, to improve the ride comfort, the study should be focused on the 3rd and 4th axles＇ suspension systems.