Numerical Simulation Of Fire Smoke Control In Atrium Space In A Mall

With the rapid development of building technology,the form of architecture is becoming more and more diverse.Among them,large-scale buildings are especially favored by designers,and the number of large space buildings in the atrium is also increasing.After a fire in the large space building of the atrium,the smoke diffuses quickly and widely.Especially in the open atrium,smoke can also easily spreads to adjacent spaces,posing a threat to personnel life safety and property loss.Therefore,the research of smoke control under the atrium space fire scene is crucial.The article combines Gambit modeling technology and Fluent simulation calculation ability of fire smoke flow field to study the smoke exhaust method in the atrium space of a large mall.The main content includes the following two aspects:(1)The influence of the position design of the physical model air inlet on the flow state of the smoke under the atrium space fire scene is discussed.The air inlet has two important functions in the simulation process: one is to provide oxidant for combustibles;the other is to eliminate the negative pressure formed in the chamber during the smoke exhaust process.In the article,the fire source is located in the center of the atrium and the fire source is located in the bottom wall of the atrium.The influence of the position of the air inlet on the flow state of the smoke is compared in the vertical direction and the horizontal direction.The results show that when the position of the two air inlets is symmetrically placed along the axis of the atrium at the first floor of the atrium,the falling velocity of the smoke layer is the fastest.Therefore,considering the most unfavorable factor when exhausting smoke,the position of the air supply port when simulating mechanical exhaust is set at the corner of the first layer.(2)According to the calculation formula of smoke emission in the large space fire scene,select the appropriate smoke machine power,and analyze the smoke control effect of the atrium space in the mechanical exhaust.When the roller shutters around the atrium space can be completely landed in time,the four exhaust vents with a size of 3m×3m can reach the level of the smoke layer at a safe height within 15 minutes under natural exhaustion.If considering the fire In the scene,the fire shutter part is partially invalid,and the maximum height of the smoke layer interface design is above 15.4m.At this time,mechanical exhaust must be adopted;on this basis,the combination of the smoke exhaust is carried out.Optimization,according to the failure of the fire shutter,to discuss the safetyrequirements under the conditions of opening different numbers of smoke exhaust,the results show that the number of smokers opened is 10,8,6,4,2,respectively the fifth layer,the fourth layer,the third layer,the second layer,and the first layer of the fire curtain are required to exhaust the smoke in the atrium space,thereby determining the opening form of the smoke exhaust in different situations.Finally,based on the research results of the article,combined with other research experiences at domestic and abroad,That puts forward reasonable suggestions for the study of smoke control in the atrium space fire.