新型磁流变隔震支座的力学动态性能研究

Study on mechanical dynamic performance of new magnetorheological isolation bearing

永磁体可对磁流变隔震支座提供一个初始磁场,设计一种利用永磁体和电磁线圈形成混合磁场功能的新型隔震支座,线圈产生的磁场调节永磁体的磁场以改变磁流变弹性体层的刚度,实现隔震支座的可变刚度性能。利用ANSYS Electronics软件对隔震支座进行仿真分析,模拟出不同电流强度下试验装置内部的磁感应强度、绘制其磁通量密度云图并计算其饱和点。制备羰基铁粉体积分数为23%的磁流变弹性体,研究隔震支座试验过程中励磁电流强度、剪切幅值及激振频率对其剪切性能的影响。结果表明:隔震支座的刚度随控制线圈电流增强而实时降低,实现磁流变弹性体隔震支座的变刚度特性;刚度软化条件下励磁电流强度、剪切幅值及激振频率对磁流变弹性体隔震支座等效刚度及等效阻尼具有显著影响。

The permanent magnet can provide an initial magnetic field for the magnetorheological isolation bearing.A new type of isolation bearing is designed by using the permanent magnet and the electromagnetic coil to form a mixed magnetic field function.The magnetic field generated by the coil adjusts the magnetic field of the permanent magnet to change the stiffness of the magnetorheological elastomer layer,and realizes the variable stiffness performance of the isolation bearing.Using ANSYS Electronics software to simulate and analyze the isolation bearing,simulate the magnetic induction intensity inside the test device under different current intensities,draw its magnetic flux density cloud map and calculate its saturation point.The magnetorheological elastomer with 23%carbonyl iron powder was prepared.The effects of excitation current intensity,shear amplitude and excitation frequency on the shear performance of the isolation bearing were studied.The results show that the stiffness of the isolation bearing decreases in real time with the increase of the control coil current,and the variable stiffness characteristics of the magnetorheological elastomer isolation bearing are realized.Under the condition of stiffness softening,the excitation current intensity,shear amplitude and excitation frequency have significant influence on the equivalent stiffness and equivalent damping of magnetorheological elastomer isolation bearing.