Влияние высоты помещения на расчётное время обнаружения пожара

Abstract

Introduction. Within the framework of this article, a quantitative and qualitative assessment of the influence of the height of the room on the estimated time of fire detection was carried out. Purpose. Assessment of the effect of the room height on the estimated fire detection time. Methods. Using the Fire Dynamics Simulator software system used to simulate the fire process, numerical experiments were carried out to study the fire detection time, which is considered in this article as an interval from the moment of fire start to reaching the values of optical density of smoke, at which point smoke fire detectors are triggered. Results and their discussion. As a result of numerical modeling of fire in rooms of different heights, data on the change in the optical density of smoke in the initial stage of fire are established. Based on the information received, the estimated time of fire detection by automatic fire alarm was determined according to the algorithms of triggering A and B at different values of permissible sensitivity for point smoke fire detectors, taking into account the height of the room. The results of numerical experiments can be used for expert assessment of the design time of fire detection as a "technical" component of the evacuation start time taken into account when determining the individual fire risk and conditions for safe evacuation of people. Conclusions. It was found that the height of the room has a slight impact on the estimated fire detection time. However, this effect is manifested in the case of the operation of point smoke detectors at the upper threshold of permissible sensitivity. To take into account the time of fire detection as part of the evacuation start time, further study of this issue is required with comparison of modeling results with the results of field experiments. Keywords: optical density of smoke; fire alarm; evacuation start time; fire detection time.