单级径向磁流变胶泥缓冲器理论分析与试验验证

Theoretical analysis and experimental verification of single-stage radial magnetorheological cement buffer

传统磁流变缓冲器通常以磁流变液作为控制介质,有着易沉降的缺点,且大多采用轴向阻尼通道,磁场利用率不高。针对这一问题,提出一种单级径向磁流变胶泥缓冲器,采用磁流变胶泥作为控制介质;为了增大磁场的利用率,建立径向阻尼通道;基于宾汉塑性模型(Bingham-plastic model,BP模型)进行理论分析,得到了阻尼通道内磁流变胶泥的速度表达式;同时考虑局部损耗的影响,建立Bingham-plastic-Minor Losses(BPM)模型。此外,搭建了落锤冲击试验平台,建立不同冲击高度、不同励磁电流下的测试条件,试验结果表明:理论模型可以很好描述缓冲峰值力到达之前的动力学行为,动态范围最高达1.28,具有良好的可控性。

Traditional MRF buffers usually use magnetorheological fluid(MRF)as control medium,which has the shortcomings prone to sedimentation and most of them use axial damping channel,which has the problem of low magnetic field utilization.For above problems,a buffer with the single-stage radial magnetorheological cement is proposed in this paper,which uses magnetorheological cement as the control medium.In order to increase the utilization of magnetic field,the radial damping channel is established.Based on Bingham plastic constitutive model(called BP model),the velocity expression of magnetorheological cement in damping channel was obtained.Considering the influence of the minor losses,Bingham plastic minor losses model(called BPM model)is established.In addition,the high-mass drop tower test platform was built to establish the test conditions under different impact heights and excitation currents.The test results show that the theoretical model can well describe the dynamic behavior before the peak force reaches,and the dynamic range is up to 1.28,which has fine controllability.