Distribution And Control Of PM2.5 Concentration In Airconditioning Room

In recent years,resulting from the aggravation of the haze,the indoor PM2.5 pollutants concentration increased,resulting in deterioration of indoor air quality.The article mainly aims at the office building,with the central air-conditioning system.Source of PM2.5 in the indoor air environment is partly from the release of PM2.5 pollution sources in the building,and the other part is the transfer of PM2.5 pollutants from outdoor air to indoor environment.Thereinto,there are no relevant domestic research reports,which are about the amount of indoor PM2.5 concentration from the central air-conditioning fresh air system and the change law of indoor PM2.5 concentration.This is at the heart of this paper.However,the study of fine particulate matter in China starts late,so there is no indoor PM2.5 concentration control value.In this paper,the indoor PM2.5 concentration control limit is proposed according to the relevant national air quality standard,that is,the standard value of PM2.5 is not more than 35 ?g/m3.In addition,for the building with a central air-conditioning system,the indoor PM2.5concentration is not only associated with the concentration of PM2.5 in the outdoor atmosphere,but also by the amount of indoor PM2.5,air-conditioning system outdoor air ratio,the central air-conditioning system purification device types and efficiency and other factors.In this paper,the PM2.5 concentration distribution model of the central air-conditioning system was established by using the computational fluid dynamics software PHOENICS as the simulation tool.Through the analysis of the simulation results under different nine conditions,the typical air-conditioning system in the different outdoor air ratio,different outdoor conditions,andrespectively in the new,return,air duct installed in different efficiency filters,this paper mainly simulates the distribution of PM2.5 pollutants concentration of a typical office room.For the use of central air-conditioning and purification system of office buildings,the indoor PM2.5 pollutants concentration does not grow with the increase in outdoor air volume.The concentration of indoor PM2.5 is related to the concentration of PM2.5 in outdoor air,the location of filter installation,the efficiency of filter and outdoor PM2.5 concentration and so on,and its concentration may decrease with the increase of outdoor air volume.Therefore,in the design,according to the different circumstances of the choice of economically reasonable outdoor air ratio and the relative air purification filter for the central air-conditioning system energy conservation and control of indoor air quality is essential.The simulation results provide a reference and suggestion for the selection of outdoor air volume and air purification equipment in the central air-conditioning system under the conditions of haze.