摘要
利用DPM-CFD模型对非均一粒径颗粒流自由下落过程中气流速度的分布规律、颗粒的扩散和运动特性进行了研究,模拟结果与实验及理论吻合良好.研究发现,空气在轴心处形成射流,其周围有漩涡产生;气流速度沿径向先减小后增加,之后再次呈现下降趋势,在轴心处速度最大,且沿轴向增加;颗粒物浓度沿径向减小,扩散半径随粒径减小而增加;随着颗粒流的下落,颗粒速度的增幅由快到慢,逐渐趋于平缓;在小颗粒中混入大颗粒可使小颗粒沉降速度减小.
Present paper presents a research of the air velocity distributions, particle diffusion and particle movement characteristic of free-fall particles with non-uniform particle diameter based on DPM-CFD model. The simulation results well matched the experimental and theoretical data. The research found that air jet forms in the axis, and vortex is produced around axis. The axis line air velocity is at a maximum, increased as the axial increasing. Besides, with the radial distance increasing, the airflow velocity increases firstly and then decreases and then increases again. The particle concentration decreases along the radial direction, and the diffusion radius increases with decreasing particle size. The particle velocity rapidly increases in the initial phase, and then gradually flatten; With the particles falling down, the increasing amount of particle velocity become smaller and smaller, and then gradually flattens; Terminal velocity of small-size particles decreases, mixed with large-size particles.
出处
《西安建筑科技大学学报（自然科学版）》
CSCD
北大核心
2015年第3期418-422,共5页
Journal of Xi'an University of Architecture & Technology(Natural Science Edition)
基金
国家自然科学基金重点项目(51238010)
国家杰出青年基金项目(51425803)
关键词
非均一粒径
颗粒速度
气流分布
数值模拟
自由下落
non-uniform particle diameter
velocity of particle
the velocity distribution
numerical simulation
free-fall
作者简介
王怡（1970-），女，教授，博士生导师，主要从事建筑通风理论及其在实际中应用研究．Email：wangyi6920@126．com
