往复活塞式发动机是汽车的主要振源,设计一套隔振良好的悬置系统以及性能合理的悬置元件是获得整车良好振动噪声特性的主要任务。首先,从黏弹性悬置的动特性及其隔振性能出发,结合发动机不平衡激励以及路面不平度激励在频率和幅值上的特点,论述了悬置的理想频变、幅变特性,以及基于传递率曲线单一不动点的隔振性能优化方法。其次,基于工程流体力学的相关理论,建立了集总参数与液力机构的结构几何相关联的惯性通道式液阻悬置的非线性集总参数模型及其等效力学模型,进而基于传递率曲线上的双不动点探讨了隔振性能优化的方法。
Reciprocating engine is main vehicle vibration source. Designing a mounting system and a set of reasonable mounts with acceptable vibration-isolation performance becomes one of the most important tasks in vehicle. Based on visco-mount dynamic properties and its vibration-isolation characteristics, considering the frequency and amplitude-dependent characteristics of engine unbalanced excitations and uneven road surface excitations, the ideal frequency- and amplitude-dependent dynamic properties for mounts, and the vibration isolation optimization method based on the single fixed-point of the transmission ratio curves are discussed. A nonlinear lumped parameter model and an equivalent mechanical model for hydraulic-engine-mounts (HEMs) with inertia track is developed based on theory of engineering hydromechanies, in which the parameters are associated with the geometry of hydraulic mechanisms. The vibrationisolation optimization method based on the dual fixed-point are illuminated theoretically.