We discuss some dynamic properties of the segregation in vertically vibrated binary granular mixtures with the same size. We present a method that can accurately calculate the order parameter in the simulation. By use of the time evolution of the order parameter, we have found that the convergence of the segregated state depends at least on the vibration amplitude, the total mass of the particles, and also the density difference between the lighter and heavier particles. The convergence is quicker for larger vibration amplitude, lighter total mass of the particles and more density difference between the lighter and heavier particles. We have also found that the fluctuation is larger even after the steady state is reached for lighter total mass of the particles and less density difference between the lighter and heavier particles.

中文翻译：

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二维密度驱动偏析的动态特性

我们讨论了具有相同尺寸的垂直振动二元颗粒混合物中分离的一些动态特性。我们提出了一种可以准确计算仿真中阶次参数的方法。通过使用有序参数的时间演化，我们发现分离状态的收敛至少取决于振动幅度、粒子的总质量以及较轻和较重粒子之间的密度差异。对于更大的振动幅度、更轻的粒子总质量以及更轻和更重粒子之间的更大密度差异，收敛更快。我们还发现，即使在粒子总质量较轻且较轻和较重粒子之间的密度差异较小的情况下达到稳定状态后，波动也会较大。