Study On Local Exhaust Flow Field Characteristics In Industrial Factory Building And Control Strategy Of Escaped Dust

It often produces a lot of high-temperature airflow with pollutant in the chemical,petroleum, metallurgy, electric power and other industries. Currently, we always use thelocal exhaust ventilation system to control pollutants. However, in industrialproduction, local exhaust ventilation systems often can not be reasonably set due tomany other factors like the requirement of the process design, space limitation andmanual operation. The control of pollutants is not ideal, there are still a large number ofpollutants escaped into the work area to impact the working environment of workers. Inthis background, author study the issue that a large number of pollutants still escapefrom the local exhaust hood. Finally, the author propose the appropriate controlstrategies on the basis of an analysis of the air flow field characteristics and particledistribution.Firstly, through comparing with the classic face-source plume formula, we canselect the applicable turbulence model for this questions which this article applies to.Then, the author analyze the influencing factors that the airflow escapes the exhausthood. It is the initial velocity of the thermal jet, the initial temperature of the hot jet, theangle of the velocity between the initial velocity and the speed of the exhaust hood. Setdifferent conditions to simulate the problem for these factors. Though the result of theairflow characteristics, we can analyze the reason why the airflow could escape from thelocal exhaust and the flow characteristics of the escaped airflow.Secondly, on the4basis of the results about the airflow, set particle phase andsimulate two-phase flow, using DPM particle trajectory discrete model. We can get the particle trajectories. So we will realize the environment of the room through thetemperature distribution of the room, the escape rate of the particle and the distributionin space of the escape particle, under the different influencing factors.Finally, on the basis of the escaped reason that this paper analyzes, we couldpropose appropriate control strategies. Such as increasing the exhaust air rate of theoriginal exhaust hood, set the paddle the original exhaust hood and set the secondaryexhaust hood. Then, analyze the control effect of several different control strategies andprovide a theoretical basis for the actual industrial production improvements.