Study On Distribution Of Gaseous Pollutants In Natural Ventilation Residences

Under the background of energy saving,people have strengthened the air-tightness of the building,leading to the reduction of indoor fresh air.On the other hand,people have improved the quality of life,and also increased the degree of interior decoration.However,the building decoration materials will release a large variety of pollutants,such as formaldehyde,toluene and other volatile organic compounds.Researches show that the hazards of these gaseous pollutants are chronic and persistent,and that several of these hazards to the human body are even more deadly.Insufficient air causes the pollutants can not be discharged effectively,and the hazards increases with the increase concentration of air pollutants.Therefore,it is necessary to study how to use natural ventilation to control indoor pollutants.In this paper,a common type residential in Xi'an was selected,which of decoration completed in seven months.Based on the ratio of the open area of the windows : 100%,75%,50%,25%,0;the indoor temperature and humidity,indoor ventilation rate,indoor formaldehyde and TVOCs concentrations,indoor particulate matter concentration,building energy consumption and other indicators were measured in the living room of the house.This paper focuses on the window area ratio and the spatial distribution of pollutants in the room and using CFD simulation calculations to expand research finally.When simulating calculation,set five kinds of window opening methods: 100%,50%,25%,2 * 50% and 2 * 25%,and which were recorded as A,B,C,D,E-model.In this paper,modeling and calculation are performed on the basis of furniture with windows and doors closed.At the same time,a model of infiltration ventilation without furniture was established and simulated.Through the analysis of the results of the field test anddiscussion of the calculation results,the main conclusions of this paper are as follows:1.In general,the bilateral ventilation effect is better than the single-side ventilation.When the ventilation is unilateral,the larger the window opening area is,the more favorable the indoor natural ventilation is.Similarly,when the window is opened bilaterally,the smaller the area of the window on each side,the worse the indoor ventilation effect.It is not that the bilateral ventilation is necessarily better than the unilateral ventilation,but when the total ventilation area is same,the bilateral ventilation is more conducive to the discharge of indoor pollutants than unilateral ventilation.2.The infiltration condition of this article is that there is 2cm gap on the outer window and a 6mm gap in the inner door.The calculation results show that this condition can not guarantee the indoor pollutant concentrations is qualified.In fact,when the outer window is closed,the gap of the outer window is smaller than2 cm.Therefore,this condition is not recommended for use in real life;3.When the outer window is opened and the inner door is closed,indoor pollutants can be effectively controlled.In all open windows conditions,D-mode is the most effective method at controlling indoor pollutants.