Simulation study on concave building facade fire suppression using drencher sprinkler
In this paper,FDS simulation software was used to investigate concave building facade insulation material fire suppression using drencher sprinkler.In the simulation,Extruded Polystyrene(XPS)was used as the typical facade thermal insulation material.Firstly,a cone calorimeter model was established to verify the rationality of XPS combustion simulation results.Secondly,a model of suppressing the fire spread on concave facades by drencher sprinkler was established.This paper studies the changes of parameters such as the time required for fire spread to the top,surface temperature and thickness of XPS under different water spray intensity,external radiant heat flux and structural factors.Based on the fact that the temperature at the measuring point 18m below the ignition point and the thickness of the insulation material hardly changed,it was determined that the water intensity could effectively suppress the spread of fire.The results show that the structural factor and external radiant heat flux are positively correlated with the surface temperature of XPS,while negatively correlated with the time required for fire spread to the top and the ignition time.When α>1.0,the effect of chimney effect on the spread of fire on the facade has a limit.The drencher sprinkler can effectively inhibit the increase of surface temperature and decrease the thickness of insulation material on the external facade of concave buildings.In the range of critical water intensity,the temperature changes at the measuring points are influenced by the chimney effect and the cooling effect of the drencher sprinkler under different a.Besides,the fire-extinguishing effect of the drencher sprinkler is also different.When the external radiation flux is 45 kW/m2 and a equals 0.4,0.8,and 1.2,the critical water intensity are 106 L/(min·m),735 L/(min·m)and 912 L/(min·m),respectively.The research results are of great significance to the fire extinguishing theory and technology of concave building exterior walls.
safety engineeringconcave buildingExtruded Polystyrene(XPS)structure factorexternal radiationcritical water intensity