棉花仓库火灾蔓延影响因素数值模拟研究

Numerical Simulation of Influencing Factors of Fire Spread in Cotton Warehouse

通过火灾模拟软件Pyro Sim建立棉花仓库火灾燃烧模型,研究棉花仓库中不同火源位置和棉垛间不同间距对仓库内火灾蔓延情况的影响。数值模拟结果显示,当火灾发生在拐角处时,火灾不易发生蔓延;当火灾发生在棉垛中间位置时,间距3 m的棉垛在100 s内就可以被点燃,火灾能够迅速在仓库内蔓延,并且在600 s左右发生轰燃,棉垛之间的走廊处和门口的开口处温度升高较快。在550 s左右顶部烟气达到1.5 m高度,将会阻挡救援人员视线,因此在此情况下灭火的最佳时间应当在550 s以内。当棉垛间距为3.5 m时,火灾没有发生蔓延,因此棉垛之间的安全间距应当设置为3.5 m。

A fire combustion model is established by the simulation software Pyro Sim in order to study the effect of different spaces and the fire position on the fire spreading in the cotton warehouse. Through the numerical simulation results,it is found that the fire is not easy to spread when the fire occurs in the corner. However,the cotton which has interval of 3 meters off the fire can be ignited in 100 seconds and the fire spread quickly in the warehouse when the fire occurs in the middle position. A flashover can be produced at the time of 600 seconds. The temperature of corridor and the gate increases faster than any other places. At 550 seconds or so,the top of the smoke will reach a height of 1. 5 meters which will block the sight of rescue personnel. The best time to extinguish the fire should be within 550 seconds. When the cotton space is enlarged to 3. 5 meters,the fire spreading will not happen. So the safety distance between the cottons should be 3. 5 meters.