Iranian Sustainable Building Scientific Association International Journal of Urban Management and Energy Sustainability 2538-1628 6 4 2025 10 01 The Effect of Wing Walls on Air Velocity Performance in Single-Sided Ventilated Spaces Using CFD 1 15 732215 10.22034/ijumes.2025.2056655.1301 EN Minoo Zidehsaraei Department of Architecture, Faculty of Art and Architecture, University of Guilan, Rasht, Iran 0000-0002-0111-7767 Amena Agharabi Department of Architecture, Faculty of Art and Architecture, University of Guilan, Rasht, Iran 0000-0001-7374-8034 Journal Article 2025 03 26 Natural ventilation in single-sided spaces often suffers from low airflow rates, which can negatively impact indoor air quality and thermal comfort. Wing walls-vertical panels installed adjacent to windows-offer potential for directing and accelerating incoming airflow; however, their optimal design parameters have not been sufficiently investigated. This study aimed to increase the average indoor air velocity in a single-sided ventilated room by incorporating a wing wall. To achieve this, the ventilation performance of several wing wall configurations with varying depths and angles was analyzed to determine the optimal depth, angle, and location. The results show that using two windows with the same total area, instead of a single window, improves both ventilation efficiency and indoor air velocity. Further enhancement was achieved by adding a perpendicular wing wall to one side of each window, which increased airflow and average indoor air velocity. Increasing wing wall depth further improved performance, with the optimal depth equal to the width of the window. Notably, movable wing walls angled at 15°, 22.5°, and 30° outperformed fixed perpendicular wing walls, delivering superior ventilation effectiveness and higher internal air velocity. This study fills a gap in natural ventilation research by simultaneously evaluating wing wall depth and angle, providing practical design guidelines for architects and engineers. Future research should examine the effects of awnings, varied opening types, movable wing walls at different heights in high-rise buildings, smart designs, and their role in cross ventilation. https://www.ijumes.com/article_732215_be796d963781970994fe919e8796c6ca.pdf