【摘要】 相对于参数模型和非参数模型,磁流变阻尼器的物理模型不需要通过实验数据进行参数识别,能够直接从物理实质上预测阻尼器的静态、动态性能,因而一直被用于磁流变阻尼器的设计和分析。为了简化问题,以往的物理模型往往都忽略了液体的惯性力。该文给出了一种简单、高效的建立可考虑液体惯性力的磁流变阻尼器瞬态有限元模型的方法。该方法的要点是:采用动网格技术来描述屈服前区厚度的发展,仅对屈服后区建立有限元模型,而把质量守恒方程和屈服前区的动力学方程作为模型的约束条件。该方法避开了在建立阻尼器瞬态有限元模型时,由粘度突变、屈服点位置依赖于阻尼力等带来的困难。与准静态模型的结果比较表明,该方法正确。结果还表明,磁场的响应是影响磁流变阻尼器瞬态阻尼力的关键,惯性力的影响很小。更多还原

【Abstract】 Compared with parametric and nonparametric models,physical models don’t require parameters iden-tification and are preferred in design and analysis of MR dampers for its direct predicting of dampers’ static and dynamic performances.However,the inertial force of MR fluid(MRF) is often neglected for simplicity in previous physical models.This paper considers the inertia of MRF and proposes a novel method to set up a transient finite element model for a MR damper by using the moving mesh in pre-yield zone flexibly.Consequently,the finite elements model is built for post-yield zone only,and both the mass conservation in dampers’ gap and the kinetic equation of pre-yield zone are implemented as the model’s constraints.In this way,difficulties arsing from the dis-continuities of viscosities and the yield point’s dependence on pressure are avoided in building a transient finite ele-ment model for a MR damper.An example of calculating transient force of a MR damper is given at the end of this paper.Agreements between state values of the transient force and results of a well-known quasi-static model validate the proposed method.The results also show that magnetic field response is the key factor affecting the transient damping force,while the effect of the inertia of MRF is negligibly small.更多还原