Influence of opening ratios and directions of windows on natural smoke exhaust effect in atrium buildings

In this paper, the influence of different opening ratios and different opening directions of the windows on the natural smoke exhaust was studied through a series of real fire experiments and simulation analysis. Increasing the open area of the window could effectively improve the overall smoke exhaust effect. When the top windows were open and the opening ratio increased from 19.2% to 24.3%, the optical density was decreased by 12.4%. The average smoke exhaust rate per unit area of the window did not change significantly. Increasing the area of the natural smoke exhaust window could effectively increase the smoke exhaust rate and improve the overall effect of smoke extraction. When the top windows were open, the temperature rise on the top floor was 30.8%–47.5% lower while the visibility was 16.8%–21.9% higher than that when the side windows were open.