Study On The Indoor Thermal Environment Of University's Classroom In Xi'an Region

The university's classroom is not only the place that teachers have lessons, but also the place that students obtain their knowledge. Because the quantity of students is more, the quality of classrooms' indoor environment has an direct effect on students' work efficiency and the health of the physiology and psychology. And that it indirectly reflects the difference of various teaching level. In order to study the thermal environment of university's classroom in Xi'an region, the author takes two lecture theater buildings in one university as an example, and analyses their indoor thermal environment both in summer and winter by objective spot test and subjective questionnaire.This thesis discovered the existent problem of indoor thermal environment of university's classroom on the basis of these methods in Xi'an region.The quality of classrooms' indoor thermal environment under natural ventilation in summer is worse, and needs further improvement. In winter the indoor temperature is higher which does not fit to work. The indoor temperature of old classrooms is somewhat low because cold wind seeps seriously and heat loses excessively. Without the ventilation facilities the indoor air quality of classrooms is even worse.The relative humidity of classrooms is lower in both winter and summer.Xi'an is located in the cold region but summer is hotter. Its thermal performance design requires to satisfy the winter thermal preservation firstly, and at the same time to keep thermal insulation in summer.This thesis proposes improvement methods aiming at the existent problem of the indoor thermal environment, on account of the influence factor of indoor thermal environment and the climate characteristic in Xi'an region. The comfortable cold of thermal environment is more favorable to work efficiency. In view of summer worse thermal environment and proper attention to winter's, this theis proposes that natural ventilation and shading facilities combined with daylighting should be used to improve the indoor thermal environment. Besides these, othercomprehensive measures like using microclimate,half underground space and plant and water and so on is feasible. In order to solve the existent problems of thermal environment in winter, building envelope should be designed to satisfy thermal preservation, and to reduce the temperature in the classroom considering the internal heat source. In view of the worse indoor air quality in heating classroom, we suggest to introduce positive air exchange facilities with function of recycling afterheat.These methods are expected to be used in new built and reconstructive classrooms in university in the future.