Investigation Of The Air Quality And Study On Purification Methods Of Air Pollutants In Train Compartment

With the application of air-conditioning in train, the airtightness is getting betterand better. And more attention is paid to the control of temperature and humidity whilethe air quality is ignored, resulting in bad condition of air quality in train compartment.The air quality of compartment has a great impact on the comfort and physical health ofpassengers and train crews. How to improve the air quality of carriage and control theconcentration of pollutants is becoming more and more important.The influences on air quality of compartment are analyzed, so are the improvingmeasures. The type and sources of main pollutants of compartment are determined byconsulting literatures.The investigations are carried on in the ordinary passenger train，multiple unit trainand subway according to the type of main pollutants, which is used to know theconcentration of pollutants. The test results show that particles, formaldehyde, bacteriaand CO₂are pollutants exceeding standard values. Furthermore, many analyses aboutparticles are made. For example, particle size distribution and particle contribution rateof fresh air and indoor. The results show that particle of compartment and supply air ismostly composed of PM1.0. And the smaller particle size is, the bigger particlecontribution rate of fresh air is. The particle contribution rate of fresh air decreases withthe increase of particle size, while contribution rate of indoor increases gradually.Based on the results of investigation, measures of improving the air quality areproposed.The technology of photoplasma is adopted for pollutants----particles, formaldehydeand bacteria. Experiment platform is built to test the performance of this technology.And the results indicate that the measure of photoplasma is feasible.For the CO₂, the model of adjusting fresh air volume is built according to theconcentration of CO₂of compartment. And the three conditions of overcrowding,attrition, and capacity status are simulated. The results show that the measure is feasibleas well.The works of this thesis provide the reference and basis for the improving of airquality of compartment, making important significance for the physical and mentalhealth of passengers and train crews.