The Research Of Air Flow Law And Pollutant Distribution Characteristics In The Reading Room Of The Library

With the rapid development of modern economy and the progress of science and technology,people gradually to the requirement of the quality of life and survival environment,indoor air quality has become a nearly 30 years a research hotspot in the field of architecture.Hidden reading integration at present,the library open management mode,service personnel in the reading room,air turbidity,readers drowsy.Some researchers used subjective testing methods such as questionnaire and experiment to the library to study indoor air quality,the main research object as,such as temperature,wind speed,the human body thermal comfort index,to human breath inside the pollutants diffusion law and concentration distribution study very little.In northern cold region a library as an example,using Swema 3000 multi-function meter instruments to library indoor temperature and humidity,wind speed,CO2 concentration and particle concentration environment parameters,such as testing,with the method of questionnaire to subjective body feeling.By comparison with test data and quantitative data of the questionnaire analysis,the research objective environmental parameters and the fitting relationship between the human body didn't feel satisfaction.Establish mathematical model and physical model of library reading room,by changing the direction of air supply,supply air velocity and supply air temperature,air supply conditions,such as study the body to release pollutants concentration distribution and the relationship between the air conditioning supply parameters,on the condition of air distribution uniformity coefficient,energy utilization coefficient and ventilation efficiency index analysis and evaluation,puts forward effective measure to control the indoor pollutants.The library reading room objective testing and subjective research results show that the indoor temperature,relative humidity,wind speed and pm 10 in accordance with national standards for air quality,CO2 concentration and pm2.5 concentrations exceed the national standard limit;Readers of the library of indoor relative humidity and the determination of the freshness of the air is not satisfaction is higher,most readers have be agitated,depressed,eye fatigue,feeling bad,resulting in a decline in the learning efficiency.Analysis of test results the following conclusions:the person's sense of the environment with its own physiological(height,weight,etc.),is engaged in the activity and psychological factors;Human perception and the ability to environmental temperature and humidity or smell is higher,indoor aerosol pollutants concentration change sensitivity is low.Simulation results show that the natural ventilation of the drainage efficiency is higher than the emission efficiency of mechanical ventilation system;Natural ventilation of the pollutant concentration field are highly dependent on outdoor wind speed and direction,is seasonal,instantaneity and uncertainty.Supply air temperature had no obvious effect on pollutants concentration distribution;Air supply velocity is inversely proportional to the concentration of indoor pollutants;Inclined down 60 0 supply compared with vertical air supply and 30° inclined downward,the uneven distribution of air coefficient,energy utilization coefficient,air distribution and ventilation system drainage efficiency has the superiority.The results show that the natural ventilation,increase in volume and change the direction of air supply can effectively improve the air quality in the reading room.Among them,the natural ventilation has a great influence on the change of indoor particulate matter concentrations,open doors and windows to increase indoor ventilation,to increase or dilute the concentration of indoor particulate matter,need to combine a day outdoor pollutant concentration fluctuations,control window period,makes the natural ventilation can not only effectively reduce the indoor concentration of other pollutants,and won't cause particulate matter pollution.Changing the direction to a certain extent,can achieve the same or even higher with the increase in gas drainage efficiency,to avoid the high speed brings a strong sense of blowing air supply,reduce air conditioning load,is conducive to building energy efficiency.Put forward a new demand control of ventilation system design idea,effectively restrain the spread of pollutants in the indoor diffusion,reduce the workers exposed to danger.