A study on the unsteady flow characteristics in a vestibule for an injection and pressurization smoke-control system

Abstract

In this study, the effects of the real-time changes of a damper's wing and the fire door on the pressure difference in an injection and pressurization smoke-control system were evaluated. The test damper, the angle of which automatically adjusts the pressure difference between the vestibules and the smoke-zone, is installed at the adjacent wall of the supply room for preventing over-pressure. The fire door, which has 900-mm width and 2000-mm height, was installed at the adjacent wall of the stairwell. As the angle of the fire door is decreased, experimental data of the inflowing air quantity and the pressure difference between the vestibule and the supply room are obtained with the angle of the damper's wing. The mass flow rate, which is a major factor in the system, is fitted with the Boltzmann function from the experiment. In addition, the resistance and the delay time of the flow coefficients introduced in this paper are used to model the numerical methods. It was systematically found that the delay time of the damper significantly affects the vestibule pressure. Finally, the numerical model was compared with the experiments for various angular velocities of the fire door and initial flow rates using pumping power. The results are in good agreement with the experiments within 5% standard deviations. (C) 2014 Elsevier Ltd. All rights reserved.