Hellen EK, Simula TP, Alava MJ
Laboratory of Physics, Helsinki University of Technology, P.O. Box 1100, FIN-02015 HUT, Finland.
Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics. 2000 Oct;62(4 Pt A):4752-6. doi: 10.1103/physreve.62.4752.
We study the dynamic scaling properties of an aggregation model in which particles obey both diffusive and driven ballistic dynamics. The diffusion constant and the velocity of a cluster of size s follow D(s) approximately s(gamma) and v(s) approximately s(delta), respectively. We determine the dynamic exponent and the phase diagram for the asymptotic aggregation behavior in one dimension in the presence of mixed dynamics. The asymptotic dynamics is dominated by the process that has the largest dynamic exponent with a crossover that is located at delta=gamma-1. The cluster size distributions scale similarly in all cases but the scaling function depends continuously on gamma and delta. For the purely diffusive case the scaling function has a transition from exponential to algebraic behavior at small argument values as gamma changes sign, whereas in the drift dominated case the scaling function always decays exponentially.
我们研究了一个聚集模型的动态标度性质，其中粒子同时遵循扩散动力学和驱动弹道动力学。大小为(s)的簇的扩散常数和速度分别近似为(D(s)\sim s^{\gamma})和(v(s)\sim s^{\delta})。我们确定了在存在混合动力学的情况下，一维渐近聚集行为的动态指数和相图。渐近动力学由具有最大动态指数的过程主导，交叉点位于(\delta = \gamma - 1)处。在所有情况下，簇大小分布的标度方式相似，但标度函数连续依赖于(\gamma)和(\delta)。对于纯扩散情况，当(\gamma)改变符号时，标度函数在小参数值处从指数行为转变为代数行为，而在漂移主导的情况下，标度函数总是呈指数衰减。
