2010, Volume 12, Issue 1
Strategic Study of CAE >> 2010, Volume 12, Issue 1
Analysis on the depositing process of the solid particulates produced by aerosol fire suppressants under fire conditionsChen
1. Institute of Disaster Prevention Science & Safety Technology, Central South Univ., Changsha 410075,China;
2. Henan Key Lab. of Preventing and Curing on Coal Mine Gas & Fire, Henan Polytechnic Univ., Jiaozuo，Henan 454003, China
Next Previous
Abstract
In this paper, unsteady analysis was conducted on the space distribution and depositing process of the solid particulates produced by aerosol fire suppressants under fire conditions. How the particles diameters affects their movement was demonstrated.The features of the particle diameters affecting the movement status were presented. The stability and resort time for the solid particles in the flow filed was explored. And the expression of the criterion (critical) diameter for a particle depositing to the fire source surface was obtained. The results demonstrated that: the depositing process of the solid particulates and the depositing Renault number are related to the particle diameter, and the flow is almost in the relatively steady flow status with low Renault number. The depositing velocity is proportional to the square of the particle diameter. When the particle diameter is lower than 100 μm, the flow will reach the steady flow status in very short time, and while the particle diameter reaches 1 μm, the particles can suspend in the space for a long time, and can be entrained into the flame region showing the extinguishing effect.
Keywords
solid particulates ; aerosol fire suppressant ; depositing process
Figures
图1
References
[ 1 ] Widmann J F, Duchez J, Yang J C, et al.Measurement of the op- tical extinction coefficient of combustion -generated aerosol [ J] . Journal of Aerosol Science, 2005 ,( 36 ) :283 -289 link1
[ 2 ] 余明高,廖光煊,张和平,等.哈龙替代产品的研究现状及发展趋势[J].火灾科学,2002,11(2):108-112 link1
[ 3 ] Kibert C J, Dierdorf D.Solid particulate aerosol fire suppressant [ J] .Fire Technology, 1994 , 4 : 387 -399 link1
[ 4 ] 傅智敏,杨荣杰.固体微粒气溶胶灭火剂的改性研究[J].火灾科学,2000,9(3):35-41 link1
[ 5 ] 杨杰.灭火气溶胶发生剂灭火机理及配方设计[J].火炸药学报,2003,26(4):84-86 link1
[ 6 ] Heinonen E W, Tapscott R E, Kibert C J, et al .Aerosol Technology Overview and Bibliography [R].WL -TR -95 -XX, 1995
[ 7 ] 杨书申,彭竹琴.气体-颗粒两相流动力学及其在气溶胶采样中的应用[J].北京:中原工学院学报,2004,15(2):59-62 link1
[ 8 ] 杜文锋.消防燃烧学[M].北京:中国人民公安大学出版社,1996
京公网安备 11010502051620号
