磁流变减振器磁场特性分析及试验研究

设计了磁流变减振器磁芯磁路,建立了磁路的仿真模型,仿真研究了磁路的磁场特性,用实验的方法对仿真模型进行了验证和修正；在此基础上,建立了整个磁流变减振器的仿真模型,仿真研究了其磁场分布规律及不同参数下阻尼孔附近的磁通密度.研究结果表明,磁芯直径、工作缸壁厚、阻尼通道长度和线圈电流是影响磁场特性的主要因素,合理选择磁路结构参数可使其性能得到最大发挥.设计并制造出一种车辆单筒充气式磁流变减振器,对其进行了台架试验,得到不同电流下的减振器示功特性图,研究发现,通过调节减振器励磁线圈中的电流获得不同强度的磁场,在磁场作用下,磁流变液粘度发生变化,从而改变减振器的阻尼特性,减振器的饱和工作电流约为2A.试验验证了磁路设计的正确性,并为实现车辆磁流变半主动空气悬架控制研究奠定了基础.

Magnetic characteristics analysis and experimental study of MR damper

The magnetic spool of MR damper was designed and magnetic circuit simulation model was established,and then the magnetic properties were analyzed.The simulation model was verified and amended by test.Complete magnetic circuit with MR fluid and cylinder was then selected as research object,and the simulation model was established with reference to the amended model,then the magnetic field distribution and magnetic flux density at the damping channel were calculated with different parameters.The results show that the spool diameter,thickness of the body,length of damping channel and the coil current have a significant effect on performance of the damper,and choosing appropriate parameters can make the magnetic function better.After having designed and fabricated the MR damper,its dynamic testing was performed on a mechanical type shock machine under sinusoidal excitation to test the damper characteristics,and the charts of damping-displacement characteristic were obtained with different electric current.It is observed that the characteristics of the MR damper change when the rheological fluid is exposed to a magnetic fleld changing its damping viscosity.The damping force increases with the applied current to reach its peak value around 2A.The results show that the magnetic design of MR damper is right,and give a reference for control strategy used to vehicle magneto-rheological semi-active suspension.