Simulation And Experimental Study On Filtration And Purification Of Fine Particles In Office Environment

Indoor environment is where people cost the longest time,indoor air quality has a direct impact on human health.Research showed that particulate matter was an important factor affecting indoor air quality.Personnel are exposed to indoor fine particles（PM2.5）for a long time.Fine particles carry toxic and harmful substances into the human body,threatening the health of personnel.With the popularization of printers in the office environment,the contact opportunities between personnel and printers have increased,and the influence of fine particles on human body has increased.Nowadays,indoor air-conditioning equipment is not enough to protect people away from fine particles.Therefore,effective measures must be taken to create a healthy working environment.Considering the problems of economy and installation,it is more reasonable to use air purifier directly than to introduce fresh air or reform the original air-conditioning system.In this paper,two kinds of common offices（two-person office and three-person office）in an administrative office building of a university in Hangzhou are taken as objects.Air purifiers with filtering and purification functions are selected to analyze the purification effect of different purification methods on indoor fine particles through simulation and experiment.Firstly,the source of fine particles in the room is analyzed,and the diffusion rule of fine particles in the printer is simulated.Secondly,according to the indoor layout,two kinds of air purifiers are selected,one is floor type with up-supply down-return,the other is wall-mounted type with up-return down-supply.The position of different air purifiers under different working conditions of the printer is simulated and analyzed.Finally,through the experimental study,the purification effect of different recycling purification methods on indoor fine particles was obtained.The results are as follows:（1）When the printer runs,the fine particles are mainly affected by the temperature rise of the airflow around the printer.The fine particles diffuse around and above the printer.When the printer and the personnel are 1 meter apart,the fine particles diffuse to the personnel position within 10seconds.（2）The influence of the position of the purifier on the purifying effect of fine particles in the room was simulated.In the two-person office,the purifier generally has two landing position（A,B）and three wall hanging position（C,D,E）.After 30 minutes,the rate of fine partical is decrease,when the printer is closed,the decreasing rate is as follows:93.8%94.4%,92.1%,87.0%,94.1%.when the printer is opened,the decreasing rate is as follows:86.8%,74.9%,72.7%,70.1%,80.5%.In the three-person office,the purifier usually landed at three locations（A₁,B₁,C₁）and four wall hangings（D₁,E₁,F₁,G₁）.After 30 minutes,the rate of fine partical is decrease,when the printer is closed,the decreasing rate is as follows:93.2%,94.5%,95.6%,88.7%,90.7%,90.0%,91.6%,when the printer is opened,the decreasing rate is as follows:78.9%,80.5%,86.0%,73.4%,74.0%,72.2%and 78.5%.（3）Experiments were carried out in a typical two-person office to test the change of fine particle concentration in the respiratory area of the purifier at five locations of A,B,C,D and E when the printer was in different states.The comparison shows that the experimental data are basically in agreement with the simulation data,and the error is less than 10%,which proves the reliability of the simulation results.It is concluded that when the printer is 1 meter away from the personnel,the fine particles diffuse to the personnel position within 10 seconds.The printer has a great impact on the health of the personnel and should be placed away from the personnel.Before the printer runs,it is necessary to open the air purifier to prevent the fine particles from diffusing to the personnel position.The effect of air purifier on the purification of fine particles is greatly affected by the location.In general,the return air outlet of the purifier is the best when it is located at the source of pollution.However,due to the influence of indoor layout,the place of the purifier is limited.When using the floor purifier,it is necessary to ensure that the air outlet is not blocked and as close as possible to the printer.The wall-mounted purifier is less restricted by layout,and it is better to close to the printer.