Airflow utilization in buildings in hot and humid areas of China

• A summer-long field study on 32 students in nine naturally ventilated buildings.
• Behavioral models were established for opening windows and doors and using fans.
• Acceptable ranges were obtained for opening windows and doors and using fans.
• A strategy for indoor airflow utilization was proposed for the hot and humid areas of China.

Airflow utilization is a traditional and effective way for people to improve their thermal comfort in summer in the areas of China that are hot and humid. We conducted a summer-long field study on nine naturally ventilated buildings in Guangzhou and collected airflow-related behaviors, motivations, and perceptions from 32 college students. The results show that the behaviors of opening windows and doors were driven by both indoor air quality and thermal comfort motivations. The proportions of open windows and doors increased linearly and slowly with the indoor ET*, and the acceptable range for opening windows and doors was an indoor ET* ≤30.3 °C with the condition that a maximum of 0.25 m/s indoor air speed needs to be achieved. The behaviors of using fans were driven by thermal comfort motivations. The proportions of use of fans increased strongly with the indoor ET*, and the acceptable range for using fans was an indoor ET* ≤31.0 °C with the condition that a maximum of 0.87 m/s indoor air speed needs to be achieved. A strategy for airflow utilization was proposed. Our study is believed to provide a better understanding of airflow-related behaviors, motivations, and perceptions as well as better designs of natural ventilation and fans and better simulations of performance for buildings in the hot and humid areas of China.