颗粒物质流变学行为和材料参数对颗粒阻尼器能量耗散的影响

Effects of rheology behaviour and material parameters of granular material on energy dissipation of a particle damper

颗粒阻尼技术(NOPD),作为一种简单有效的振动控制手段被广泛应用于各种场合。基于离散单元法仿真,结合NOPD中颗粒系统的运动状态对阻尼效果进行分析,探究不同振动条件对阻尼性能的影响,从细观尺度阐述颗粒系统的能量耗散机理。并通过正交试验,考察颗粒的密度、剪切模量、恢复系数、静摩擦因数、滚动摩擦因数等材料参数对损耗因子的影响。研究结果表明,颗粒系统表现出不同运动状态时的流变学行为及细观结构导致了阻尼效果的变化,颗粒系统在浮力对流状态时表现出最优的阻尼效果。不同的颗粒材料参数在不同颗粒系统运动状态条件下对系统阻尼的影响程度不同。

The non-obstructive particle damping(NOPD)has been widely used for its simplicity and high efficiency in attenuating structure vibration.In this paper,the discrete element method(DEM)was applied in the simulation.The damping effectiveness of NOPD was analyzed combining with the motion modes of the granular system to obtain the influence of different vibration conditions on damping property.And the energy dissipation mechanism was illustrated at the meso-scale.The effects of the material parameters of particle on the loss factor including density,shear modulus,coefficient of restitution,coefficient of static friction,coefficient of rolling friction were also studied based on the orthogonal experiment method.The results show that the different motion modes of rheology behaviors and the meso-structure lead to variations of the damping effectiveness.The NOPD achieves the optimal performance and better operation in the buoyancy convection state.In addition,the effective weights of the material parameters of particle are different.The coefficient of static friction and density play important roles in the damping effectiveness of the granular system.