Study on utilization efficiency and control of water mist in flame plume areas

doi:10.16265/j.cnki.issn1003-3033.2019.11.007

Abstract

Abstract: In order to improve fire extinguishing efficiency of water mist, its cooling effect on flame is studied. Firstly, a motion, heat and mass transfer model of water mist in flame areas were established which was utilized to evaluate factors that affected its penetration distance and vaporization performance comprehensively. Then, a method to reasonably identify initial size and velocity of droplets and a co-flow jet water mist system which could improve utilization efficiency were proposed.The results show that those factors rank according to their influence degree from high to low is initial size of droplets, heat transfer temperature difference, initial velocity of droplets, flame plume velocity. Penetration distance and vaporization rate of water mist can be significantly improved by this system.

Key words: flame plume, water mist, penetration distance, vaporization performance, co-flow jet water mist system

CLC Number:

X932

HE Mingli, ZHANG Guang, HU Shaohua, LIU Yan. Study on utilization efficiency and control of water mist in flame plume areas[J]. China Safety Science Journal, 2019, 29(11): 39-44.

References

[1] PANCAWARDANI F, ARINI D, YUNINDAR R P, et al. Analysis of water mist fire suppression system applied on cellulose fire[J]. Procedia Engineering, 2017, 170: 344-351.
[2] 杨克,邢志祥,纪虹,等. 超细水雾抑制甲烷爆炸的影响因素研究[J]. 中国安全科学学报, 2018, 28(11): 70-75.
YANG Ke, XING Zhixiang, JI Hong, et al. Analysis of factors influencing air-methane explosion suppression by ultrafine water mist [J]. China Safety Science Journal, 2018, 28(11): 70-75.
[3] LIU Z, CARPENTER D, KIM A K. Cooling characteristics of hot oil pool by water mist during fire suppression[J]. Fire Safety Journal, 2008, 43(4): 269-281.
[4] 张青松, 程相静, 白伟. 细水雾添加剂抑制锂电池火灾最佳浓度研究[J]. 中国安全生产科学技术, 2018, 14(5): 43-50.
ZHANG Qingsong, CHENG Xiangjing,BAI Wei. Study on optimum concentration of additives in water mist for suppression of lithium battery fire[J]. Journal of Safety Science and Technology, 2018, 14(5): 43-50.
[5] 翟毅. 油浸式变压器消防安全问题探讨[J]. 建筑电气, 2015, 34(10): 27-29.
ZHAI Yi. Discussion on fire safety problems of oil-immersed transformers[J]. Building Electricity, 2015, 34(10): 27-29.
[6] 胡清华. 高压细水雾在地铁设备用房灭火中的应用[J]. 铁道勘察, 2011(3): 107-110.
HU Qinghua. Applications of thin water fog system with high pressure for fire extinguishment of subway facility room[J]. Railway Investigation and Surveying, 2011(3): 107-110.
[7] 张天巍, 杜志明, 刘凯. 细水雾扑灭食用油火的有效性及影响因素研究[J]. 中国安全科学学报, 2015, 25(7): 55-61.
ZHANG Tianwei, DU Zhiming, LIU Kai. Study on effectiveness of water mist in suppressing cooking oil fire and factors affecting it[J]. China Safety Science Journal, 2015, 25(7): 55-61.
[8] 葛晓霞, 张学魁. 细水雾灭火系统技术研究进展[J]. 火灾科学, 2006, 2(5): 170-175.
GE Xiaoxia, ZHANG Xuekui. Review on water mist fire suppression system[J]. Fire Science, 2006, 2(5): 170-175.
[9] MAWHINNEY J R, RICHARDSON J K. A review of water mist fire suppression research and development[J]. Fire Technology, 1997, 33(1): 54-90.
[10] WIGHUS R. Extinguishment of enclosed gas fires with water sprays[J]. Nasa Sti/Recon Technical Report N, 1991, 94: 997-1 006.
[11] 黄鑫, 刘江虹, 廖光煊, 等. 细水雾扑灭油池火的临界条件[J]. 燃烧科学与技术, 2006, 12(4): 323-328.
HUANG Xin, LIU Jianghong, LIAO Guangxuan, et al. Critical condition of pool fire suppression by water mist[J]. Journal of Combustion Science and Technology, 2006, 12(4): 323-328.
[12] ZEGERS E, WILLIAMS B A, SHEINSON R S, et al. Dynamics and suppression effectiveness of monodisperse water droplets in non-premixed counterflow flames[J]. Proceedings of the Combustion Institute, 2000, 28(2): 2 931-2 937.
[13] CHELLIAH H K, LAZZARINI A K, WANIGARATHNE P C, et al. Inhibition of premixed and non-premixed flames with fine droplets of water and solutions[J]. Proceedings of the Combustion Institute, 2002, 29: 369-376.
[14] STRIZHAK P A, VOLKOV R S. The integral characteristics of the deceleration and entrainment of water droplets by the counter flow of high-temperature combustion products[J]. Experimental Thermal and Fluid Science, 2016, 75: 54-65.
[15] 张志荣, 冉景煜. 低温低速烟气中液滴破碎临界韦伯数与破碎时间分析[J]. 中国电机工程学报, 2012, 32(5): 78-85.
ZHANG Zhirong, RAN Jingyu. Analysis on critical We and breakup time during breakup of droplet in low temperature and low velocity flue gas[J]. Proceedings of the Chinese Society for Electrical Engineering, 2012, 32(5): 78-85.
[16] THOMAS G O. The quenching of laminar methane-air flames by water mists[J]. Combustion and Flame, 2002, 130(1): 147-160.
[17] RAMÍREZ C A. Summary of frictional drag coefficient relationships for spheres: evolving solution strategies applied to an old problem[J]. Chemical Engineering Science, 2017, 168: 339-343.
[18] SAZHIN S S. Advanced models of fuel droplet heating and evaporation[J]. Progress in Energy and Combustion Science, 2006, 32(2): 162-214.
[19] NOVOZHILOV V, HARVIE D, KENT J H, et al. A computational fluid dynamics study of wood fire extinguishment by water sprinkler[J]. Fire Safety Journal, 1997, 29(4): 259-282.
[20] VAARI J. A transient one-zone computer model for total flooding water mist fire suppression in ventilated enclosures[J]. Fire Safety Journal, 2002, 37(3): 229-257.
[21] VOLKOV R S, STRIZHAK P A. Motion of water droplets in the counter flow of high-temperature combustion products[J]. Heat and Mass Transfer, 2018, 54(1): 193-207.
[22] FERRAND V, BAZILE R, BOREE J, et al. Gas-droplet turbulent velocity correlations and two-phase interaction in an axisymmetric jet laden with partly responsive droplets[J]. International Journal of Multiphase Flow, 2003, 29: 195-217.
[23] MI J, NOBES D S, NATHAN G J. Influence of jet exit conditions on the passive scalar field of an axisymmetric free jet[J]. Journal of Fluid Mechanics, 2001, 432: 91-125.
[24] LAU T, NATHAN G J. Influence of stokes number on the velocity and concentration distributions in particle-laden jets[J]. Journal of Fluid Mechanics, 2014, 757: 432-457.