汽车动力总成液阻悬置液-固耦合非线性动力学仿真

液阻悬置是一种先进的隔振元件,广泛应用于汽车动力总成的隔振系统中。目前对液阻悬置动特性的仿真均采用集总参数模型,模型所需的物理参数主要由液阻悬置相应的元件进行试验得到。以惯性通道-解耦盘式液阻悬置为研究对象,建立了其性能分析的液-固耦合有限元模型;利用该模型对其静、动特性进行了仿真,并和试验值进行了对比。计算分析了液阻悬置的-些内部特征参数的变化规律,其结果与液阻悬置的工作机理或试验结果相符合。利用液-固耦合有限元模型对液阻悬置进行仿真时,只需橡胶材料的应力-应变关系、液体的性能参数和液阻悬置的几何参数。应用该法可以在液阻悬置的设计开发阶段较精确地预测产品的性能和进行优化设计,有利于提高产品设计质量、缩短开发周期。

NONLINEAR MODELING OF HYDRAULIC ENGINE MOUNTS OF A CAR POWERTRAIN WITH COMPUTATIONAL FLUID STRUCTURE INTERACTION FINITE ELEMENT ANALYSIS MODELS

Hydraulic engine mount (HEM) is a highly effective vibration isolator, and is widely used in automotive powertrain. A lumped parameter model is a traditional model for modeling the dynamic characteristics of the HEM, and the system parameters in the model are usually obtained by experiments. A fluid structure interaction (FSI) finite element analysis (FEA) model is established for the dynamic analysis of an HEM with an inertia track and a free decoupler. The static and dynamic characteristics of the HEM are predicted with the FSI FEA model and the results are compared favorably with experimental data. Calculated results of the time histories of some variables in the model, such as the pressure in upper chamber and the displacement of free decoupler under different excitations, elucidate the working mechanism of the HEM. Only stress versus strain relations of the rubber materials, the fluid physical parameters and the HEM's sizes are needed for the simulation of a HEM with the FSI FEA model, and no prototype mounts or parts need to be prefabricated in the design stages, thus greatly reducing mount design time.