基于离散单元法的二维颗粒阻尼研究  

Numerical study of particle damping in two dimensions by use of discrete element method

作　　者：唐伟[1] 王延荣[1] 王相平[2] 杨剑秋[1] 

机构地区：[1]北京航空航天大学能源与动力工程学院,北京100191 [2]中国航空工业集团公司沈阳航空发动机设计研究所,沈阳110015

出　　处：《航空动力学报》2011年第5期1159-1165,共7页Journal of Aerospace Power

基　　金：国家重点基础研究发展计划(2007CB210103)

摘　　要：针对自由端带空腔的L型悬臂梁建立了二维颗粒阻尼物理模型,发展并利用离散单元法(DEM)对二维颗粒阻尼进行了数值仿真,重点考查了二维空腔尺寸对颗粒阻尼的影响规律:①高度非线性的颗粒阻尼能够显著地抑制结构振动,阻尼值至少比金属材料阻尼大一个数量级;②当无量纲加速度Γ<1时,颗粒阻尼很小;当Γ>1时,随Γ增加,颗粒阻尼先增大后减小,即存在临界无量纲加速度使得阻尼最大;③颗粒阻尼的峰值随水平无量纲碰撞间隙的增加而增大,并向Γ减小方向略微偏移;而随垂直无量纲碰撞间隙增加,该峰值也增大,但却向Γ增大方向偏移.所发展方法的计算值与实验结果吻合很好,可用于颗粒阻尼器的设计及应用.The physical model of particle damping in two dimensions was developed for the cavity with particles inside located at the free end of an L-shaped beam,and discrete element method（DEM） was used to investigate the effects of two-dimensional cavity sizes on particle damping.The results show that：（1） the highly nonlinear particle damping,which is at least one order of magnitude higher than the intrinsic material damping of metals,can significantly suppress the vibration of structures;（2） when dimensionless acceleration amplitude Γ〈1,particle damping is very small;however,when Γ〉1,it firstly increases and then decreases with the increase of Γ,indicating that there is a critical dimensionless acceleration amplitude for the highest damping;（3） the peak value of particle damping increases and appreciably shifts to the lower Γ with the increase of horizontal dimensionless impact clearance.However,it also increases but shifts to a higher Γ with the increase of vertical dimensionless impact clearances.The simulation results agree well with the experimental data,and can be applied to the practical design of a particle damper.

关 键 词：颗粒阻尼 离散单元法(DEM) 振动抑制 空腔尺寸 非线性阻尼 

分 类 号：V231.92[航空宇航科学与技术—航空宇航推进理论与工程]