盘形缝隙式双筒MRD阻尼力模型与分析

Model and Analysis of Damping for Twin-tube Magneto-rheological Fluid Damper Based on Disc Type Orifice

设计出一种基于被动式双筒液压减振器的盘形缝隙式双筒磁流变液减振器(Magneto-rheological fluid damper,MRD),并根据牛顿流体在平行圆盘缝隙间流动的层流模型和磁流变液(Magneto-rheological fluid,MRF)的Bingham本构关系,推导出盘形缝隙式双筒MRD的阻尼力计算模型。提出衡量MRD性能的最重要参数之一阻尼力可调倍数的定义,依据力学模型推导出其计算公式。对公式中影响MRD的阻尼力可调倍数各种因素进行分析,得出在零磁场强时阻尼力不变的情况下提高阻尼力可调倍数的途径。对设计的盘形缝隙式双筒MRD进行台架试验,验证了所推导的力学模型的准确性。通过对三种不同缝隙高度的MRD的试验数据进行分析,得出阻尼可调系数随盘形缝隙高度的变化关系。分析不同电流下低温MRD随着液体温度的升高对可调阻尼力的影响。

A new disc type orifice magneto-rheological fluid damper（MRD） based on passive twin-tube hydraulic damper is designed,and its calculation model of the damping force is deduced through laminar flow model of Newton-fluid in disc type orifice and Bingham constitutive relation of Magneto-rheological fluid（MRF）.The definition of adjustable multiple of damping force,which is one of the most important performance parameters of MRD,is put forward,and its formula is also deduced on the basis of the mechanical model.By analyzing various factors in the formula that influence the adjustable multiple of damping force,the way of increasing the adjustable multiple with constant damping force and zero magnetic-field intensity is obtained.At last,bench test of the designed MRD is carried out,and the correctness of the derived mechanical model is verified.The relation between the adjustable coefficient and the disc type orifice height is obtained through the analysis of the test data of MRDs with three different orifice heights.Additionally,the influence of fluid temperature rise in low-temperature MRD at different currents on the adjustable damping force is analyzed.