Study On Simulation Of Extrusive Flame Through Several Longitudinal Windows Spreading Based On FDS

In the modern city of reinforced concrete,high-rise building row upon row have sprung up,along with the fire risk caused by that is increasing day by day.When high-rise building fires occur outside spread,due to the rapid spread of fire and the size of the fire,the fire is difficult to implement rapid fire rescue,which cause the people’s lives and property great losses.In order to effectively prevent the fire from spreading,the interaction and the mechanism of the interaction of window flame is the key.In recent years,scholars have carried out a systematic and thorough study on the interaction and integration mechanism of flame.In the field of building fires,most of the research has focused on the interaction between single window flame and thermal insulation materials,but the research of the interaction between the flame of window and the flame of the external wall thermal insulation material,especially the temperature field,velocity field and flame height of the multi window,is less.According to the theory of fire,This paper use FDS fire dynamics simulation software,for easy to form flame ejected from window of the small space of residential buildings(without spraying facilities),commercial office buildings and hotels(with spraying facilities),to establish seven full-scale model,considering without longitudinal fire prevention measures and with longitudinal fire prevention measures,and study on numerical simulation of multi window spouts flame to get fusion flame temperature field distribution,the airflow velocity field and flame height variation and reveal merging flame combustion characteristics.The research results can provide reference for the prevention and control measures of fire spread in high-rise buildings,and have great significance for the fire prevention design in the practical engineering.The main conclusions of this paper are as follows:(1)Without longitudinal fire prevention measures:When Fire HRR is 3MW(with spraying facilities),vertical two window form 0.5m high limit of the merging flame and the flame speed can reach 4.5m/s,and longitudinal impact height is 6m.When Fire HRR is 6MW(without spraying facilities),the longitudinal two window can form the 1.7m high limit merging flame and the flame speed can reach 5m/s,and the longitudinal impact height is 4m.(2)With fireproof eave longitudinal fire prevention measures:When Fire HRR is 3MW(with spraying facilities),1.0m and 1.2m fireproof eave can effectively prevent the formation of effective multi window merging flame,and get the merging flame high-speed airflow away from the building facade 2m outside,and can not form effective longitudinal impact height.When Fire HRR is 6MW(without spraying facilities),when fireproof eave is 1.0m,longitudinal limit of two window merging flame focused on bottom of fireproof eave,and longitudinal impact height from 1.5m single window fell to multi window Om.When fireproof eave is 1.2m,it did not form effective multi window merging flame and longitudinal impact height.