施工场地扬尘排放运移特征研究

Study on Characteristics of Dust Emission and Transportation in Construction Sites

施工场地内粉尘的运移规律对研究颗粒污染和净化等有很大作用,为有效解决施工中产生的粉尘污染问题,探究粉尘飘散规律,以某工程扬尘状况为研究对象,利用Fluent软件,运用欧拉-拉格朗日气-尘颗粒两相流动数学模型,模拟不同粒径粉尘在不同风速下受工地有无围挡阻隔的飘散效应。研究结果表明:无围挡作用时风速由1.6 m/s增大至6.7 m/s时,扬尘浓度显著提高;有围挡作用时形成较大负压,对后方粉尘扩散有抑制作用;围挡距离尘源扩大到10 m时,抑制作用最明显,且风速达到6.7 m/s以上时可以减弱扬尘向围挡后上方的扩散作用;所得结论为粉尘防治和相关人员的保护提供科学对策,现场应用效果较好。

The law of dust migration in the construction site has a great effect on the study of particle pollution and purification.In order to effectively solve the dust pollution during construction,the dust drift law is explored.The dust situation of a project is taken as the research object,and the Fluent software is used.The Euler-Lagrangian gas-dust particle two-phase flow mathematical model is applied to simulate the drift effect of different particle size dusts at different wind speeds on the site.The research results show that the dust concentration is significantly increased when the wind speed is increased from 1.6 m/s to 6.7 m/s without the enclosure;when the enclosure is used,a large negative pressure is formed,which inhibits the rear dust diffusion;when the dust source is expanded to 10 m,the inhibition effect is most obvious,and when the wind speed reaches 6.7 m/s or more,the diffusion of dust to the upper part of the enclosure can be weakened;the conclusions provide scientific countermeasures for dust prevention and related personnel protection,and the field application effect is better.