Evolution of planetesimal velocities
Evolution of planetesimal velocities
复制标题
行星速度的演化
DOI：
10.1016/0019-1035(88)90120-0
复制
发表时间：
1988
期刊：
影响因子：
3.2
通讯作者：
G. Wetherill
中科院分区：
文献类型：
--
作者：
G. Stewart;G. Wetherill
本文给出了一般微星群体速度演化的自洽方程组。这些方程是以一种便于计算行星积累早期阶段的形式给出的，当有必要用气体动力学的方法来模拟微行星群时，而不是遵循单个天体的轨道演化。为了说明这些方程的各个方面的相对重要性，一个简单的微行星人口的稳态速度，由两个不同大小的机构，计算。动力摩擦被认为是一个重要的机制，从较大的微行星的动能转移到较小的，提供了一个能源的小微行星，这是由粘性搅拌过程所提供的。当小微行星相对丰富时，气体阻力和较小天体之间的非弹性碰撞对于耗散星群中的能量具有相当重要的意义。
A self-consistent set of equations for the velocity evolution of a general planetesimal population is presented. The equations are given in a form convenient for calculations of the early stages of planetary accumulation, when it is necessary to model the planetesimal swarm by the methods of gas dynamics, rather than follow the orbital evolution of individual bodies. To illustrate the relative importance of the various terms of these equations, steady-state velocities of a simple planetesimal population, consisting of two different sizes of bodies, are calculated. Dynamical friction is found to be an important mechanism for transferring kinetic energy from the larger planetesimals to the smaller ones, providing an energy source for the small planetesimals that is comparable to that provided by the viscous stirring process. When small planetesimals are relatively abundant, gas drag and inelastic collisions among the smaller bodies are of comparable importance for dissipating energy from the population.