A granular flow model for dense planetary rings
A granular flow model for dense planetary rings
复制标题
致密行星环的颗粒流模型
DOI：
10.1016/0019-1035(85)90054-5
复制
发表时间：
1985
期刊：
影响因子：
3.2
通讯作者：
S. Tremaine
中科院分区：
文献类型：
--
作者：
N. Borderies;P. Goldreich;S. Tremaine
我们研究了在颗粒密集且其集体行为类似于液体的极限情况下差动旋转颗粒盘的粘度。压力张量源自流体动力学方程和 Haff (1983) 描述的简单碰撞动力学模型。我们发现，如果应用液体近似，密度波和窄圆环是不稳定的。由此产生的非线性扰动可能会导致环材料在垂直方向上“飞溅”。这些结果可能有助于理解小环椭圆度的起源、土星B环外缘附近的非轴对称特征，以及土星环和天王星环运动学模型中无法解释的残差。
We study the viscosity of a differentially rotating particle disk in the limiting case where the particles are densely packed and their collective behavior resembles that of a liquid. The pressure tensor is derived from the equations of hydrodynamics and from a simple kinetic model of collisions described by Haff (1983). We find that density waves and narrow circular rings are unstable if the liquid approximation applies. The resulting development of nonlinear perturbations may give rise to “splashing” of the ring material in the vertical direction. These results may help in understanding the origin of the ellipticities of ringlets, the nonaxisymmetric features near the outer edge of the Saturnian B ring, and the unexplained residuals in kinematic models of the Saturnian and Uranian rings.