摘要
为提高水成膜泡沫灭火剂(AFFF)扑灭柴油池火的灭火性能,利用自组泡沫灭火系统装置对不同气液体积流量比(气液比)、系统压力和泡沫混合液体积流量下水成膜泡沫灭火剂在柴油池火中的灭火效能进行了研究。结果表明:当气液比为16时,AFFF灭火时间最短为42 s、灭火剂用量最少为210 g,表现出最佳的灭火效能;随系统压力增加,灭火时间和灭火剂用量逐渐减少,其中系统压力0. 5 MPa时AFFF的灭火时间和灭火剂用量相较于0. 3 MPa时分别下降了40. 7%和21. 1%;此外,泡沫灭火剂的灭火效能还随泡沫混合液体积流量增大而提高,其中泡沫体积流量60 L/h时灭火时间和灭火剂用量相比于20 L/h时分别下降了35. 7%和5. 4%。红外热成像分析表明,AFFF在灭火过程中主要通过其优异的冷却和覆盖隔离作用使火焰无法维持正常燃烧而熄灭,达到较好的降温和灭火效果。
In order to improve the fire extinguishing efficiency of aqueous film-forming foam(AFFF)in the diesel oil pool fire,the present paper has carefully studied the influences of the gasliquid ratio,the system pressure and volume flow rate of the foam liquid on the fire extinguishing of AFFF via a self-built foam extinguishing device.The results show that AFFF with a gas-liquid ratio of 16 has the shortest fire extinguishing time of 42 s and the lowest AFFF solution consumption of 210 g,so as to exhibit the best fire extinguishing performance.The fire extinguishing efficiency of AFFF can be improved with the increase of the system pressure,and the AFFF with the system pressure being of 0.5 MPa,that is,the lowest fire extinguishing time of 16 s and AFFF solution consumption of 172 g during the fire extinguishing process,which are 40.7%and 21.1%lower,respectively,as compared to the case of 0.3 MPa.The fire extinguishing efficiency of the AFFF can also increase with the rising volume flow rate of the foaming liquid,and the fire extinguishing rate and the solution consumption of AFFF with the foam volume flowing rate of60 L/h are 35.7%and 5.4%lower,respectively,as compared to those of 20 L/h.The infrared imaging analysis indicates that the size of the combustion zone decreases with the decrease of the area of fuel vapor production due to the spreading foam.When the area is totally covered,sufficient amounts of air cannot reach the liquid fuel and then extinguishment occurs.As the fuel is covered,cooling occurs to bring about the vapor pressure of the fuel below that of its boiling point.Once the fuel is cooled,a layer of foam continues to be applied either manually or by spreading to the terminate combustion and/or by preventing the re-ignition.The main fire extinguishing mechanism of AFFF can be ascribed to the barrier effect and cooling effect of the foam to suppress the flame.
作者
徐志胜
郭星
颜龙
康文东
贾宏煜
XU Zhi-sheng;GUO Xing;YAN Long;KANG Wen-dong;JIA Hong-yu(Institute of Disaster Prevention Science and Safety Technology,Central South University,Changsha 410075,China)
出处
《安全与环境学报》
CAS
CSCD
北大核心
2020年第2期489-494,共6页
Journal of Safety and Environment
基金
国家自然科学基金项目(51676210,51906261)
湖南省自然科学基金项目(2018JJ3668)
中南大学研究生自主探索创新项目(2019zzts617)。
关键词
安全工程
水成膜泡沫灭火剂
灭火效能
气液体积流量比
safety engineering
aqueous film-forming foam
fire extinguishing efficiency
gas-liquid ratio
