Study of Smoke Stratification in Atrium Halls Using Scale Model

Abstract

Nowadays, atrium building is very popular because it can provide extensity and attraction to the users even if they are inside the enclosed environment. Similar to other buildings, fire safety is one of the major concerns especially the atrium are linked to shopping arcades. The major challenge is to control the smoke movement in the case of fire and maintain a stable smoke layer clear height to allow sufficient time for the occupants to evacuate from the building. Therefore, an efficient smoke management system (SMS) is necessary. For the SMS to function properly, the smoke behaviour inside the atrium must be studied. One of the phenomena affecting the operation of the SMS is smoke stratification. That is, due to the vertical temperature gradient inside the atrium, a thermally stratified environment is formed and smoke will not be able to reach the smoke detectors/smoke outlets in the ceiling. In the past decade, various studies were conducted to study the smoke filling process in the atrium. Only a few studies were carried out to study smoke stratification in atrium. This paper attempted to study the factors leading to the development of thermally stratified environment in an atrium and the formation of smoke stratification under the ceiling space of an atrium building using scale model. These factors included the temperature of the smoke plume, the air temperature under the ceiling, the configuration of roof ceiling and the ambient air temperature. Two types of ceiling configurations such as a cuboid and a triangular prism are used. Data concerning the ceiling air temperature, smoke plume temperature, effect of different ceiling configuration and maximum smoke layer height in a thermally stratified environment are collected. Comparisons are conducted with the calculated results from National Fire Protection Association (NFPA) 92B equations. With all these information, better design criteria of smoke detection system, SMS in an atrium building can be developed. Finally, the experimental results can be used to investigate the discrepancies between the experimental measurement and the calculated results from NFPA 92B equations. Put abstract text here.