Numerical Simulation Study On The Influence Of Water Sprinkler On Fire Smoke Flow Of The Building Fire

With the accelerating of urbanization process, all kinds of buildings increase rapidly, and fire hazard increased. Automatic water spray system due to its high sensitivity and reliable fire extinguishing, economical and practical, easy to maintenance etc are widely used in building fire prevention. Understand the influence of water sprinkler on fire smoke flow can provide theory basis for nozzle rational arrangement, in order to expressing best control effect of water sprinkler.This paper based on computational fluid dynamics theory and FDS simulation software platform, we study the influence of different water sprinkler on fire smoke flow by theory analysis and simulation study, in order to draw the influence rule of different spray conditions on fire smoke flow. First of all, on the basis of smoke flow theory and sprinkler spray theory, we point out the dangers of fire smoke to evacuation, and the drag of water droplet will cause the unstability of smoke layer, then smoke congestion, congestion jet and wake flow occurred, they obstruct the safety evacuation of people. Then, combined with actual situation of a reading room to divide grid and select the simulation time, besides these, we choose the appropriate fire load, fire development model and spray parameters to set up8spray scenario, and then use the Pyrosim and FDS to set up the fire flow field simulation model of the reading room under the water spray. Finally, we research and analysis the eight scenarios.We can conclude that:the activation of water spray not only restrains the fire growth, but also control the fire smoke near the ceiling, it can ensure the safety of evacuation of non-fire area, but at the same time, it will hinder smoke emission, speed up the smoke layer thickening and the visibility reducing, the produce a lot of CO, but the peak of CO concentration is reduced during the whole process; With the same spray distance, increasing single sprinkler discharge rate can reduce smoke temperature and increase CO concentration, it makes the scence of fire more chaos.; With the same single sprinkler discharge rate, shorten the spray distance can reduce the peak of temperature, slow down the speed of smoke temperature, at the same time the smoke turbulence intensified. The research process and conclusions can provide the reference for fire safety design of the similar buildings, and has the certain practical significance of safety evacuation.