Study Of Fire Plume In Limited Space Of Buildings And Fire Resistance Of Structure Considering Location Of Fire Source

There are many vertical shafts in high rise buildings.These vertical shafts will accelerate the spread of fire as a result of the stack effect.It will be more difficult to fight fires.The characteristics of fire plume have been studied in this paper.Considering the position of the fire source and the opening area of the vertical shaft,a series of experiments have been carried out.In addition,considering that the temperature distribution is affected by the position of the fire source,Fire Dynamic Simulator has been used to achieve the temperature around the steel frame,and thermal-structural coupled analysis has been carried out by using ABAQUS.The main work of this paper is as follows:(1)The fire plume temperature distribution in vertical shaft has been studied in this paper,and it is found that the temperature distribution in vertical shafts correlates well with the McCaffrey's theory,which has been widely used in open space.The temperature in continous region is smaller than that in open space.The air entrainment coefficient increase with the increase of the opening area,and the ratio of air entrainment can be estimate by the opening area and the distance.(2)The flame length has been studied in this paper,it has been found that the flame length decrease with the increase of the opening area and the distance.The flame length when the distance is zero is proportional to the 2/3 power value of the heat release rate,and the ratio of the flame length is constant with the change of the heat release rate.Based on the distance and the opening area,the relationship between the flame height and these factors can be achieved.(3)The temperature around the steel frame has been achieved by using FDS,and based on the temperature,thermal-structural coupled analysis has been carried out by using ABAQUS.