垂直激振条件下二元颗粒的能量损耗

Energy loss of binary particles under condition of vertical vibration

为提高振动条件下颗粒体系能量耗散水平,设计二元颗粒阻尼器的悬臂梁振动实验,采用稳态功率流法计算颗粒体系功率损耗,分析垂直激振条件下的二元颗粒体系处于分层和混合状态下的流动形态和能耗水平。结果表明:第2颗粒的引入增加颗粒体系内部的不均匀性,加剧颗粒体系的碰撞和摩擦作用,二元颗粒在分层或者混合情况下,能耗水平均高于一元颗粒;分层时,不同的粒径配比对应不同的能耗水平,粒径比为1.67时有最优能耗;质量较小的颗粒处于底层或者质量较小的颗粒有更多质量占比时,颗粒体系有更好的能量耗散效果;混合时,颗粒混合程度不影响能量损耗,二元混合颗粒在大振幅和高频率激振条件下相对一元颗粒有更显著的能耗提升效果,较小颗粒最优质量占比随振幅的提高而增大。

To improve the energy dissipation of particle damper,dynamic experiment about binary particles was designed.We adopted the steady state power flow method to calculate the power loss of particle system and analyzed the flow patterns and energy consumption of binary particle system under the state of layering and mixing.The results show that the other kind of particles increase the internal non-uniformity of particle system which intensify the internal collision and friction of particle system.It can be seen that binary particles have higher energy consumption level than homogeneous particles no matter in hierarchical or mixed case.When binary particles are layered,different diameter ratio will get different energy levels and it will reach the optimal energy consumption at the diameter ratio of 1.67.Those particles with smaller mass bottom or greater quantity of small particles contained can obtain further energy dissipation.When binary particles are mixed,the mixed degree does not affect the energy loss.The binary mixed particles have more significant promotion effect of energy consumption under the condition of large amplitude and high frequency excitation.And the optimal quality of the smaller balls increases with the rise of amplitude.