Comparison of Wind-Driven Natural Ventilation for Different Windows in a Room with a Single Opening

Abstract

In order to get more effective natural ventilation into a room with a single sided opening or large depth, two new window types have been developed in the laboratory. These are based on three new patent developments. The first window is defined as a dual level ‘up-down folio’ window which consists of two pairs of openable sashes with one pair placed directly above the other. The second is a multi-sash mid-pivoted window with vertical deflectors. The performance of these new window designs were compared with a conventional side-hung window and sliding window by installing them, in turn, into a single sided opening space of a test room. Both spot measurements and CFD analysis were undertaken. Wind-driven ventilation performance was analysed in each case for three wind speeds 1 m/s, 2 m/s and 3 m/s and five wind angles 0°, 22.5°, 45°, 67.5° and 90°. It was concluded that for the single sided test case, the two new window designs provided room air velocities that were more uniform and with higher mass flow rates that occurred for the two conventional window types. However, further substantial studies are needed to improve these designs and popularise these new types of windows.