论文标题
在旋转激发下粒状物质中密度波的自发形成
Spontaneous formation of density waves in granular matter under swirling excitation
论文作者
论文摘要
我们在这里研究水平圆摇下的谷物亚层的自发聚类。当将振荡振幅增加到阈值之外时，晶粒的聚类就会发生。密集的区域以驱动频率以圆形方式行驶，甚至超过了驾驶速度。事实证明，观察到的聚类是由于密度波的形成。对现象学模型的分析表明，均匀密度曲线的不稳定性是通过增加振荡振幅而产生的，并捕获了聚类对系统全局密度的过渡幅度的非单调依赖性。在这里，关键成分是单个晶粒的速度随局部密度的增加而增加。耗散粒子粒子相互作用和底物的摩擦驱动的相互作用导致该依赖性，该依赖性通过离散元素方法模拟进行了测试。
We study here the spontaneous clustering of a submonolayer of grains under horizontal circular shaking. The clustering of grains occurs when increasing the oscillation amplitude beyond a threshold. The dense area travels in a circular fashion at the driving frequency, even exceeds the speed of driving. It turns out that the observed clustering is due to the formation of density wave. The analysis of a phenomenological model shows that the instability of the uniform density profile arises by increasing the oscillation amplitude and captures the non-monotonic dependence of the transition amplitude of the clustering on the global density of the system. Here, the key ingredient is that the velocity of individual grains increases with the local density. The interplay of dissipative particle-particle interaction and the frictional driving of the substrate results into this dependence, which is tested with discrete element method simulations.
