给出表征液阻悬置动态特性与激振频率相关性的5参数分数导数模型,模型中的5个参数具有明确的物理意义。以一个含有液阻悬置的2自由度振动系统为研究对象,以被支撑物体的垂直位移和侧倾角的时域响应为优化目标,对液阻悬置的动态特性进行优化。计算和试验结果表明,5参数分数导数模型能较好地表征液阻悬置动态特性的频率相关性,提出的基于控制系统方框图的时域分析方法,可以用于含有液阻悬置振动系统的动态响应分析和对液阻悬置的动态特性进行优化。
A five-parameter fractional derivative model for characterizing the relations between excitation frequencies and dynamic properties of a hydraulic engine mount (HEM) is presented, and the five parameters in the model have definite physical meanings. A two-degrees-of-freedom vibration system containing two HEMs is considered, and the dynamic properties of the two HEMs are optimized with the aim of controlling the vertical displacement and the roll angle of the supported object in time domain. Calculation and test results demonstrate that the five-parameter fractional derivative model can describe the frequency-dependent dynamic properties of the HEMs efficiently. The time-domain response analysis method based on the block diagram can be used to analyze the dynamic responses of the vibration systems including HEMs, and the optimization method developed in this paper can be used to optimize the dynamic properties of the HEMs.