双组分颗粒振动体系中的能量传递与耗散

Energy transfer and dissipation in a binary granular mixture under vibration

为研究颗粒床层中的能量传递及耗散规律,基于离散元(DEM)法模拟一维垂直振动床内组分颗粒的受激运动,得到单组分和双组分颗粒的能量分布规律.结果表明:不同振动参数(振幅和频率)下颗粒体系的能量传递与耗散规律存在明显的差别,高频振动下颗粒体系的动能和耗散随着床层高度的增加而减小,低频振动下则呈现与之相反的变化趋势;对于双组分颗粒混合物床层,系统的总动能受振动参数和床内颗粒分布形式的影响;低频率低振幅时,"反巴西果"分布的床层总动能更低,高频率条件下的"巴西果"分布时床层总动能更低.

Energy transfer and dissipation in a vibrated granular bed was studied by DEM simulations,and the energy profile in the granular bed of the same size and binary mixture were obtained.The results show that the energy transfer and dissipation in the granular bed are influenced by the vibration parameters（vibration amplitude and frequency）.Along the bed height,the kinetic energy of grains decreases at high vibration frequency,while it increases at low vibration frequency.For the granular bed constituted by a binary mixture,the total kinetic energy is influenced by the grain distribution of mixture in bed beside frequency and amplitude.For low frequency amplitude vibrations,the granular bed with ＂Reverse Brazil Nut＂distribution has lower energy.While,for high frequency vibration,the energy of bed with ＂Brazil Nut＂distribution is much lower.