MR-J型磁流变阻尼器性能测试与阻尼力预估模型

磁流变阻尼器阻尼力预估模型易受磁流变液磁感应强度一剪切屈服强度（B－τ）曲曲线精度及磁芯饱和效应的影响．导致阻尼器的预估阻尼力与实际阻尼力有较大偏差．针对上述问题，设计并制作了2个磁芯可更换的MR—J型磁流变阻尼器，通过对阻尼器的磁场分布和动力性能的测试，研究了磁芯面积、活塞节段数及磁场分布对阻尼器力学性能的影响：结合实测结果与有限元分析结果，提出了B－τ曲线的实用识别方法，建立了考虑磁芯饱和效应的阻尼力预估模型研究表明：磁流变阻尼器的磁场分布和阻尼力随磁动势上升存在明显的磁芯饱和效应，且阻尼器的饱和磁动势随磁芯面积增大而增大；所提出的磁流变液B－τ曲线实用识别方法能正确描述阻尼器实际工作状态下磁流变液的性能参数：所提出的阻尼力预估模型能较为精确地预估磁流变阻尼器的实际阻尼力．

Performance Test and Prediction Model of Damping Force of MR-J Dampers

Affected by the accuracy of the magnetic induction intensity B and shearing yield strength r curve and the magnetic saturation phenomenon ,the accuracy of the traditional model for predicting damping force is not satisfactory and the predicted damping force is different from the actual damping force. In order to solve this problem,2 MR dampers with changeable magnetic core were designed and produced, and the influence of area of magnetic core ,number of stages of the piston and magnetic field distribution on the mechanical properties of the MR dampers was studied through magnetic field test and dynamic test. An algorithm of practical B-r curve was proposed based on test results and finite element analysis and a refined prediction model of damping force was put forward in which the effect of magnetic saturation phenomenon was put into consideration. Study results show that there is obviously magnetic saturation effect with the magnetic field distribution and the damping force,and the saturation magnetic motive force rises with the increase of the area of magnetic core. The proposed algorithm of practical B-r curve can precisely describe the behavior of MR fluid in the actual working state. The proposed prediction model can predict the actual damping force of the MR dampers precisely.