非球形颗粒布朗运动的涨落-格子Boltzmann数值研究

计算物理 ›› 2012, Vol. 29 ›› Issue (1): 101-107.

非球形颗粒布朗运动的涨落-格子Boltzmann数值研究

聂德明, 林建忠

中国计量学院计量测试工程学院, 杭州 310018

收稿日期:2011-04-11 修回日期:2011-07-27 出版日期:2012-01-25 发布日期:2012-01-25
作者简介:聂德明(1979-),男,博士,讲师,主要从事颗粒多相流研究,E-mail:nieinhz@cjlu.edu.cn
基金资助:
国家自然科学基金重点项目(11132008)资助

Brownian Motion of Non-spherical Particles:Fluctuating-Lattice Boltzmann Investigation

NIE Deming, LIN Jianzhong

College of Metrology and Technology Engineering, China Jiliang University, Hangzhou 310018, China

Received:2011-04-11 Revised:2011-07-27 Online:2012-01-25 Published:2012-01-25

摘要/Abstract

摘要： 采用涨落-格子Boltzmann方法对非球形颗粒(二维)的布朗运动进行直接数值模拟.数值结果包括椭圆形、矩形颗粒的速度均方值及速度自相关函数等.研究发现,对于非球形颗粒,其方向性并没有影响能量均分原理的适用性,每个自由度的能量由其速度或角速度的均方值确定,而且计算的颗粒平动温度和转动温度一致.此外,颗粒的速度自相关函数在相对长的时间内以~ct^-1的规律衰减,其系数c与颗粒的形状无关.

关键词: 布朗运动, 涨落-格子Boltzmann方法, 非球形颗粒

Abstract: A fluctuating-lattice Boltzmann method is used for direct numerical simulations of Brownian motion of non-spherical particles. Numerical results include mean-square velocities and velocity autocorrelation functions of elliptical and rectangular particles. It showns that equi-partition theorem applies to non-spherical particles as well and energy of each degree of freedom depends on corresponding mean-square velocity or rotational velocity. Furthermore, translational temperature of Brownian particle is identical to its rotational temperature. Finally, velocity autocorrelation function of Brownian particle decays at relative long times as~ct^-1, where coefficlent c is independent of particle shape.

Key words: Brownian motion, fluctuating lattice Boltzmann method, non-spherical particl

中图分类号:

O359

聂德明, 林建忠. 非球形颗粒布朗运动的涨落-格子Boltzmann数值研究[J]. 计算物理, 2012, 29(1): 101-107.

NIE Deming, LIN Jianzhong. Brownian Motion of Non-spherical Particles:Fluctuating-Lattice Boltzmann Investigation[J]. CHINESE JOURNAL OF COMPUTATIONAL PHYSICS, 2012, 29(1): 101-107.