Spatial Density Distributions and Correlations in a Quasi-one-Dimensional Polydisperse Granular Gas

• 来源期刊: 理论物理通讯(英文版)
• 年，卷（期）: 2009,（2）
• 页码范围: 259-264
• 页数: 6页
• 语种: 英文

摘要

By Monte Carlo simulations, the effect of the dispersion of particle size distribution on the spatial density distributions and correlations of a quasi one-dimensional polydisperse granular gas with fractal size distribution is in-vestigated in the same inelasticity.The dispersive degree of the particle size distribution can be measured by a fractal dimension df, and the smooth particles are constrained to move along a circle of length L, colliding inelastically with each other and thermalized by a viscosity heat bath.When the typical relaxation time T of the driving Brownian process is longer than the mean collision time TC, the system can reach a nonequilibrium steady state.The average energy of the system decays exponentially with time towards a stable asymptotic value, and the energy relaxation time TB tO the steady state becomes shorter with increasing values of df.In the steady state, the spatial density distribution becomes more clusterized as df increases, which can be quantitatively characterized by statistical entropy of the system.Furthermore, the spatial correlation functions of density and velocities are found to be a power-law form for small separation distance of particles, and both of the correlations become stronger with the increase of dr.Also, the density clusterization is explained from the correlations.