基于IHBM的汽车非线性悬架系统定量研究

分析了汽车悬架系统和轮胎的非线性弹簧力和阻尼力,建立了二自由度汽车非线性垂向振动系统的动力学模型.结合增量谐波平衡方法(incremental harmonic balance method,IHBM),对该系统的动力学行为进行定量研究.推导其增量谐波平衡过程,研究增量谐波平衡法的迭代计算过程,采用几个不同的谐波次数,计算系统的近似周期解,确定周期解的稳定性;同时,以路面激励圆频率为参数进行了跟踪计算,得到系统主共振时的幅频响应特性.近似解的计算结果与数值计算结果的对比表明,增量谐波平衡方法的精度可灵活控制,且收敛速度快,结果可靠,是汽车强非线性动力学行为研究的有效方法.

Quantitative Study of Automotive Nonlinear Suspension System Based on Incremental Harmonic Balance Method

Based on an analysis of nonlinear spring forces and damping forces for automotive suspension and tire,a nonlinear dynamic model of automobile heave vibration system with two degress of freedom (DOF) was built.Then,an incremental harmonic balance method (IHBM) was adopted to quantitatively study the system.The process of IHBM was derived,and the iterative process was studied.Meanwhile,the steady periodic solution of automobile nonlinear system was obtained with some harmonic numbers and stability of the periodic solution was studied as well.Based on the tracing calculation with the circular frequency of road excitation as parameter,the amplitude-frequency response characteristic of the system at the primary resonance was obtained.The numerical simulation of the approximate periodic solution by the IHBM was compared with the numerical method.Results show that the IHBM is an effective way to analyze both weak and strong nonlinear dynamics in engineering practice.