基于离散相模型的铀尾矿砂大气迁移数值模拟  

Numerical simulation of atmosphere migration of uranium tailings grit based on DPM

作　　者：万芬[1] 彭小勇[1] 谢清芳[1] 张欣[1] 黄帅[1] 

机构地区：[1]南华大学城市建设学院,湖南衡阳421001

出　　处：《安全与环境学报》2013年第1期96-101,共6页Journal of Safety and Environment

基　　金：国家自然科学基金项目(11075072)

摘　　要：基于不可压缩N-S方程和离散相模型(Discrete Phase Model,DPM),用数值方法研究了粒径为10μm、50μm、100μm、150μm的铀尾矿库滩面颗粒在0.5m/s、1 m/s、2m/s和4m/s风速下的运动轨迹和沉降规律。结果表明,颗粒的运动轨迹同时受到风速和粒径的影响,不同粒径的颗粒在不同风速下运动轨迹相差较大,粒径为10μm的颗粒比粒径为150μm的颗粒在尾矿库下风向的运动随机性要大得多。在同样的大气迁移距离内,0.5 m/s风速下10μm粒径的颗粒所花的时间是4m/s风速的12倍。在相同的风速下,10μm粒径颗粒的迁移距离要远大于150μm粒径颗粒的迁移距离,且150μm粒径颗粒大部分在尾矿库下风向800m内沉积。Based on the incompressible Navier-Stokes equation and discrete phase model （DPM）, the present paper is engaged in pursu- ing the particle-migrating trajectory and settlement regularity of the pond-side particles at uranium tailing ponds. According to our test, the downward wind direction the size of the tailing pond is about 500 m ×500 m, while the beach surface is 400 m × 400 m at a height of 30 m. The DPM we have adopted is a discrete random model usually used for exploring the effect of the particle size and wind velocity on the particle trajectory. The sizes of the said particles are about 10 μm, 50μm, 100μm, 150 μm under the different wind velocities of about 0.5 m/s, 1 m/s, 2 m/s, and 4 m/s in our numerical simula- tion. The results of our test show that the movement condition of par- ticles seems quite complicated and sometimes irregular in the down- ward wind direction of the tailings pond while the wind velocities and the particle sizes prove to have a certain influence on the trajectory of the particles. Usually, the trajectory of the particles of different sizes under different wind velocities tends to be quite different when the randomness of 10μm particles at the downwind direction of the tailing pond proves stronger than that of 150μm particles. More specifically speaking, the granular migration distance under the smaller wind ve- locity proves much smaller than that under the strong wind with other indexes being equal. Wind velocity is the important factors of parti- cles which depart from beach face of uranium tailing pond. Under the same migration distance, the length of time the 10 150 μm particles of 0.5 m/s wind velocity experience would be 12 times of 4 m/s. And, therefore, the smaller wind velocity is beneficial for the parti- cles to settle down. In addition, the migration distance of 10 μm par- ticles is far greater than that of 150 μm particles under the same wind velocity, though most of the smaller particles may travel the whole flying field, the escaping from the export

关 键 词：环境工程学 铀尾矿库 DPM 数值模拟 运动轨迹 大气迁移 

分 类 号：TL752.2[核科学技术—辐射防护及环境保护]