Investigation of indoor air quality in libraries using CFD analysis method

Library buildings are among the complex indoor environments that require special consideration in terms of indoor air quality (IAQ) due to prolonged occupancy, high user density, diverse ventilation conditions, and the presence of archival materials that must be preserved. Users' cognitive performance, comfort perception, and health status, as well as the physical durability of library collections, are directly influenced by these environmental conditions. However, the literature reveals that studies on IAQ in library buildings are limited in number and often focus on short-term observations with a narrow set of parameters. In this context, this master's thesis presents a comprehensive evaluation of indoor air quality in libraries through an integrated approach combining on-site measurements, spatial interpolation, and computational fluid dynamics (CFD) modeling. Two different library buildings located in Antalya, Türkiye, were selected as the case studies: Antalya Library and the Central Library of Akdeniz University. These buildings were chosen due to their differing sizes, architectural characteristics, user densities, and ventilation systems, making them suitable for comparative analysis. In Antalya Library, measurements were conducted at 11 different locations, while in Akdeniz University Library, 7 locations were selected. At each location, detailed measurements were taken at three different height levels (0.5 m, 1.2 m, and 1.8 m). The measured parameters included particulate matter fractions (PM0.3, PM0.5, PM1, PM2.5, PM5, PM10), carbon dioxide (CO₂), and ambient temperature (AT). All measurements were conducted using the PCE-PCO 2 particle counter and the JD-3002 CO₂ meter. In addition to statistical analyses, the field data were used as input for CFD modeling performed using Flow-3D software. During the modeling process, detailed three-dimensional geometric models were created by incorporating the architectural layouts of the library buildings and the physical features of their ventilation systems. Through CFD simulations, not only particle concentrations but also airflow patterns, stagnant zones, and particle transport dynamics were thoroughly analyzed. The findings of this study led to several practical and research-based recommendations for optimizing IAQ in libraries. It is recommended to enhance filtration quality in ventilation systems, implement CO₂-based dynamic ventilation control systems, increase the supply of fresh air during periods of high occupancy, ensure regular HVAC maintenance and filter replacement, and employ low-emission cleaning systems. Furthermore, for future research, it is suggested to conduct long-term monitoring studies, chemical characterization of particulate matter, and detailed investigations into the relationships between IAQ, user health, and cognitive performance.