Painter B, Behringer RP
Department of Physics and Center for Nonlinear and Complex Systems, Duke University, Durham, North Carolina 27708-0305, USA.
Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics. 2000 Aug;62(2 Pt B):2380-7. doi: 10.1103/physreve.62.2380.
We experimentally examine the dynamics of two-particle collisions occurring on a surface. We find that in two-particle collisions a standard coefficient of restitution model may not capture crucial dynamics of the system. Instead, for a typical collision, the particles involved slide relative to the substrate for a substantial time following the collision; during this time they experience very high frictional forces. The frictional forces lead to energy losses that are typically larger by a factor of 5-6 than the losses due to particle inelasticity. In addition, momentum can be transferred to the substrate, so that the momentum of the two particles is not necessarily conserved. Finally, we measure the angular momenta of particles immediately following the collision, and find that angular momentum can be lost to the substrate following the collision as well.
我们通过实验研究了发生在表面上的两粒子碰撞的动力学。我们发现，在两粒子碰撞中，标准的恢复系数模型可能无法捕捉系统的关键动力学。相反，对于典型的碰撞，碰撞后参与碰撞的粒子会相对于基底滑动相当长的时间；在此期间，它们会受到非常大的摩擦力。摩擦力导致的能量损失通常比粒子非弹性导致的损失大5到6倍。此外，动量可以传递给基底，因此两个粒子的动量不一定守恒。最后，我们测量了碰撞后立即的粒子角动量，发现碰撞后角动量也会损失到基底。
