Students’ thermal comfort and cognitive performance in fan-assisted naturally ventilated classrooms in tropical Singapore

Fan-assisted cooling strategies are widely employed in tropical climates due to their energy-saving benefits while ensuring thermal comfort through increased air temperature and air velocity. This study conducted experiments involving secondary school students in fan-assisted naturally ventilated classrooms in tropical Singapore. A total of thirty-six students from two secondary schools participated in this study. The classroom thermal environment was measured, students' thermal comfort was surveyed, physiological responses were monitored, and students' cognitive performance was assessed in different classrooms with various fan configurations. Thermal comfort survey results indicated that students' thermal comfort can be maintained at neutral with elevated air velocity, when classroom temperature remained at or below 30 °C. Students' wrist skin temperature, arm skin temperature, and heart rate showed significant differences under various thermal conditions and thermal sensations, suggesting the potential use of physiological parameters to predict students' thermal comfort in fan-assisted naturally ventilated classrooms. This study also observed a significant impact of classroom thermal condition on students' cognitive performance. It was found in both schools that students' cognitive performance scores decreased significantly with increased temperature and decreased air velocity. Additionally, students' cognitive performance decreased by 9.2% and 18.1% in slightly warm and warm sensations, respectively, compared to the neutral sensation. These findings underscore the significance of air velocity as a crucial factor in the design of classroom environments, particularly in tropical climates, to enhance students' thermal comfort and optimize their cognitive performance.