Study on factors influencing performance of ventilation tower used for natural ventilation

For the purpose of saving energy, the number of cases in which cross-ventilation systems have been introduced in buildings is increasing. Previous studies have revealed that the use of a ventilation tower is effective in improving cross-ventilation and ventilation performance. In this study, the factors influencing cross-ventilation performance are identified by focusing on the shape of the ventilation tower, and an effective natural ventilation system is proposed. Furthermore, we investigate the influence of setting improvement model of cross-ventilation performance on a building what having ventilation. As a result, the screen model of the ventilation tower that had a simpler shape (cylindrical in shape and including four screens) exhibited an improved cross-ventilation performance. The screen model had screens with a width of five times that of the opening on the target building, and the cross-ventilation performance obtained was more efficient than that obtained in previous studies. Therefore, in this study, we developed a method for improving the cross-ventilation performance of a building that has a ventilation void.