针对非阻塞性颗粒阻尼(Non-obstructive Particle Damping,NOPD)在微重力、超重及离心等非常态环境中减振效果较差的问题,采用重力加速度表征这些非常态物理环境,利用离散元法(Discrete Element Method,DEM)研究重力参数对NOPD减振特性的影响,同时还分析NOPD最优填充比及最优粒径比等结构参数在不同重力条件下的变化规律。研究表明,重力加速度在0。7~1。0 g之间时NOPD减振效果最好。在微重力环境下,当重力参数变化时,NOPD最优填充比为0。85,最优粒径比为0。45。而当重力加速度大于1g时,NOPD最优填充比及最优粒径比均随重力加速度的增加而减小,且其最优范围也均有所扩大。
Influences of Different Gravity on Damping Performances of Non-obstructive Particle Dampers
To improve the damping performances of non-obstructive particle damper(NOPD)in abnormal environments such as the micro-gravity conditions,hyper-gravity environments and centrifugal environments,the discrete element method(DEM)is adopted to investigate the effects of different gravity on the damping performances of NOPD,and the structural parameters such as the optimal filling ratio and the optimal diameter rate of particles under different gravity conditions are also analyzed.The results show that the damping effects of NOPD are the best when the gravity acceleration is between 0.7 and 1.0 g.In addition,in the micro-gravity environments,the optimal filling ratio and the optimal diameter rate of particles remain constants no matter the change of gravity parameters,which are 0.85 and 0.45,respectively.When the gravity acceleration is greater than 1.0 g,the optimal filling ratio and the optimal diameter rate of particles and cavity of NOPD decrease with the increase of gravity acceleration,and their optimal ranges are expanded.
vibration and waveNOPDabnormal environmentsgravity parameterfilling ratiodiameter rate of particle and cavity