Preliminary numerical analysis of thermal comfort and CO₂ distribution toward the application of fabric air dispersion systems in lecture halls

In educational spaces, ensuring indoor environmental uniformity is essential for maintaining occupants’ performance, particularly under ongoing high-temperature conditions. Accordingly, this study serves as a preliminary stage for the application of fabric air dispersion (FAD) systems in educational spaces. Through a parametric numerical scenario study that considers occupancy and ventilation requirements, it aims to evaluate the expected effects of FAD application and to explore operational directions. On-site monitoring and computational fluid dynamics (CFD) simulations were conducted to evaluate thermal comfort and CO₂ distribution, and the baseline model was validated. Multiple regression analysis identified key environmental variables influencing predicted mean vote (PMV) and CO₂, which were further verified through indoor environmental uniformity analysis. The findings indicated that applying the FAD system demonstrated expected effects related to achieving a more stable and uniform spatial distribution of indoor environmental conditions. Even under high occupancy, PMV remained within the comfort range with a difference of 0.5, indicating uniform thermal conditions. CO₂ concentration decreased by about 1,000 ppm, but further ventilation strategies were required to achieve additional CO₂ reduction. The most effective strategy was to increase the exhaust velocity to 4 m/s, which enabled 67 % of the occupied zone to maintain CO₂ levels within 1,000–1,500 ppm with acceptable thermal comfort. While this scenario suggests a potential operational direction when considering the application of the FAD system, further optimization of ventilation control is needed to achieve CO₂ levels below 1,000 ppm.