Effect Of Indoor Air Quality In Classroom On College Students’ Thermal Comfort During Class In High-Humidity Region

The indoor air environment of university classrooms may be closely related to students’comfort,which affects students’learning efficiency.With the development of social economy and students’higher and higher requirements for the quality of learning environment,creating a healthy and comfortable learning environment has become a hot research issue in recent years.Taking the urban area of Chongqing as the representative of high humidity area,this paper analyzes the impact of classroom air environment in different class types,different seasons and different seat areas on indoor students’comfort in high humidity area,summarizes the influence law of college classroom indoor environment on students’comfort,and puts forward the optimal control strategy of college classroom air environment.The main contents are as follows:firstly,the situation of different types of real classroom scenes in a university in Chongqing is investigated,and the changes of hot and humid environment and air quality in classrooms in different seasons in Chongqing are analyzed and summarized.We conducted a comfort questionnaire survey in summer,autumn and winter,and conducted on-site detection of indoor temperature,humidity,PM_2.5,PM₁₀ and CO₂ during class.At the same time,the comfort experiments of real control scenes are set up in summer and winter respectively.The number of people in each laboratory is 40,including 20 men and 20 women.The temperature parameters of on-site air conditioning are controlled.Students fill in the questionnaire at a certain interval to summarize the comfort of students under different working conditions under the control scene.The research results provide evidence for the control strategy of indoor heat and humidity environment and air quality during college classroom in high humidity areas,and provide a reference for the determination of temperature and humidity control threshold in college classroom in different seasons and different class types.The main results of this paper are as follows:（1）In summer,the temperature of multiple measuring points in large classes is higher than the standard value of 28℃,and the concentrations of indoor inhalable particulate matter PM₁₀and PM_2.5 do not exceed the standard value;In winter,there is a large difference in CO₂concentration among indoor areas in large classes,and the CO₂ concentration in most areas exceeds 1000ppm.The average value of indoor CO₂ in small classes in autumn is 766ppm,which does not exceed 1000ppm;The concentrations of PM_2.5 and PM₁₀ in all indoor areas of the small class in winter exceeded the standard value,and the CO₂ concentration in all indoor areas exceeded 1000ppm about 20min after class.（2）During the summer classes of large classes,the comfortable indoor temperature for students is 27.7℃～28.0℃,and the middle door and rear door areas are more comfortable;The comfortable temperature of students in large classes in autumn is 21.0℃～21.5℃,and the middle door and rear window areas are more comfortable;The comfortable temperature range of students in large classes in winter is 18.5℃～18.8℃.At this time,the front door and rear window areas are more in line with this temperature range.The comfortable indoor temperature for students in small classes in autumn is 22.0℃～22.6℃.The front,middle and middle door areas are more in line with this range;The comfortable indoor temperature of students in small classes in winter is 16.8℃～18.3℃.（3）The comfortable temperature range of students in the control scene in summer is28.2℃～28.5℃.The front door with natural ventilation and setting temperature of 26℃,the rear middle and rear window with setting temperature of 27℃and the rear window area with setting temperature of 28℃all meet the temperature range and meet the comfort needs of students.The comfortable temperature range of students in the winter control scene is 18.0℃～19.1℃.The front window,middle door,middle center,rear door and rear window areas with a temperature of 18℃all meet the temperature range and meet the comfort needs of students.It is proposed that the indoor temperature of university classrooms in high humidity areas should be controlled at 26℃in summer;In high humidity areas that can meet students’thermal comfort needs in winter,the indoor temperature of university classrooms during class is controlled to be 18℃,and it is suggested that the heating temperature should be set to 18℃to better meet students’thermal comfort.