A Study On The Air Quality And Foam Propagation Characteristics Of College Classroom

Building indoor environment has been one of the outer environments people contact most freduently, modern people spent more than about90%of the time indoors, indoor air quality on human heslth is self-evident. In addition, indoor air quality will have important effect on our working and learning efficiency. As the classroom is a important place for teachers impart knowledge and students acquire knowledge, so we should take more focus on the indoor air quality of the classroom. Domestic univicity classrooms especially early in most classrooms built with natural ventilation. Because of simple ventilation and a large stsff density in classrooms, environmental issues in the classroom can not be underestimated.Inorder to fully understand the university classroom in hot summer and cold winter area indoor air quality situation, this article will use live tests, questionnaires and numerical simulations to study the indoor air quality of university’s classroom in Nanjing. Main works are as follows. A naturally ventilated university in Nanjing was investigated to continuous monitor the CO2concentration, temperature and humidity. At the same time, we will investigate the indoor air quality of the classroom by questionnaires. Use the method of mathematical statistics and objective analysis of the data. Analyze the affecting factors such as the sension, the classroom position, the personnel density and the opening of the doors and windows. And combined with the climate of in hot summer and cold winter area, some suggestions may be proposed to improve the indoor air quality. Additional, we will use FLUENT software to simulate the flow field of typical classroom. Comparsion the diffrenet flow field between school classroom with exam classroom. And the changing rules of indoor temperatures, velocities and CO2concentration in the circumstances of different ventilation conditionwere known from the analyse.The results show that the subjective investigation and test results are in good accordance, that the air quality of the university classrooms is not very good. High indoor pollutant concentration has a significant adverse impact on the learning efficiency of the students. For the classrooms, the indoor CO2concentration in exceed of most serious is in November and December and March, with the maximum CO2concentration up to5199ppm. When all of the windows and doors shut, the growth rate of the indoor CO2concentration is inversely proportional to the area of the classroom. In order to solve the indoor air quality of the naturally ventilated classrooms, we should increase the ventilation rate and decrease occupant density. The simulation results show that relative to the school classroom, the changing of indoor temperatures, velocities and CO2concentration in exam classromm is more uniform. And increasing the number of windows and doors could decrease the indoor CO2concentration, but the indoor thermal comfort will be affected.Because of the simple ventilation and a large stsff density of the classroom in university, mang diseases would easily spread in the school especially in winter and spring. This paper will use FLUENT software to simulate the droplet exhale from the student in the naturally ventilated classrooms. And we will simulate the droplet diameter of10μm,50μm,100μm and120μm.