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

作　　者：CHEN Zhi-Yuan ZHANG Duan-Ming 

机构地区：[1]School of Electronic and Information Engineering, Xianning College, Xianning 437100, China [2]Department of Physics, Huazhong University of Science and Technology, Wuhan 430074, China

出　　处：《Communications in Theoretical Physics》2009年第2期259-264,共6页理论物理通讯（英文版）

基　　金：supported by National Natural Science Foundation of China under Grant Nos.10675048 and 1068006;the Natural Science Foundation of Xianning College under Grant No.KZ0916

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 investigated in the same inelasticity. The dispersive degree of the particle size distribution can be measured by a fractal dimension dr, 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 τ of the driving Brownian process is longer than the mean collision time To, 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 τB 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 df. Also, tile density clusterization is explained from the correlations.

关 键 词：granular gas INELASTICITY fractal dimension df spatial density distributions spatial correlationsof density and velocities 

分 类 号：O171[理学—数学] TL631.24[理学—基础数学]