Brilliantov N V, Pöschel T, Kranz W T, Zippelius A
Institute of Physics, University of Potsdam, Am Neuen Palais 10, 14469 Potsdam, Germany.
Phys Rev Lett. 2007 Mar 23;98(12):128001. doi: 10.1103/PhysRevLett.98.128001.
In a granular gas of rough particles the axis of rotation is shown to be correlated with the translational velocity of the particles. The average relative orientation of angular and linear velocities depends on the parameters which characterize the dissipative nature of the collision. We derive a simple theory for these correlations and validate it with numerical simulations for a wide range of coefficients of normal and tangential restitution. The limit of smooth spheres is shown to be singular: even an arbitrarily small roughness of the particles gives rise to orientational correlations.
在由粗糙颗粒组成的颗粒气体中，旋转轴与颗粒的平动速度相关。角速度和线速度的平均相对取向取决于表征碰撞耗散性质的参数。我们推导了这些相关性的简单理论，并通过数值模拟对广泛的法向和切向恢复系数进行了验证。光滑球体的极限情况显示出其特殊性：即使颗粒的粗糙度任意小，也会产生取向相关性。
