SPECIAL ISSUE: PUBLIC SAFETY |
|
|
|
|
|
Flame spread and combustion characteristics of straw bales from a point fire source |
DU Wei1, CHEN Haitao1, ZOU Biao1, REN Weida1, ZHU Xiaokang1, LI Cong2 |
1. State Grid General Aviation Company Limited, Beijing 102219, China; 2. School of Emergency Management and Safety Engineering, China University of Mining & Technology (Beijing), Beijing 100083, China |
|
|
Abstract Combustion experiments were conducted with cylindrical straw bales with various diameters and thicknesses. The flame spread and flame structure were analyzed with a model developed to predict the mass loss rate (ṁ) and flame temperature. The flame structure progresses from a hollow conical flame to a separated annular flame and then a broken annular flame. The mass loss rate first increases and then slowly decreases. The peak mass loss rate is linearly related to the initial straw mass, which implies that a larger initial mass increases the heat accumulation during the straw combustion. The flame temperature distribution along the vertical axis has the same trend as the mass loss rate with the dimensionless flame temperature decreasing slowly with increasing (z-z0)ṁ-2/5 for small values of this parameter and then decreasing more quickly at larger values of (z-z0)ṁ-2/5. (z-z0 is the relative flame height.) The conclusions deepen the understanding of straw fire development and spread characteristics.
|
Keywords
wildfires
point fire source
flame spread
annular flame
mass loss rate
|
Issue Date: 06 May 2022
|
|
|
[1] 狄丽颖, 孙仁义. 中国森林火灾研究综述[J]. 灾害学, 2007, 22(4):118-123. DI L Y, SUN R Y. Summarization of research on forest fire in China[J]. Journal of Catastrophology, 2007, 22(4):118-123. (in Chinese) [2] 魏博, 陈丽娟, 阿依谢姆古丽·赛来, 等. 玉米秸秆成型颗粒高温热解和燃烧特性研究[J]. 新疆大学学报(自然科学版), 2021, 38(6):685-690. WEI B, CHEN L J, AYIXIEMUGULI S, et al. Study on high-temperature pyrolysis and combustion characteristics of corn straw briquettes[J]. Journal of Xinjiang University (Natural Science Edition in Chinese and English), 2021, 38(6):685-690. (in Chinese) [3] 谢腾, 王雅君, 丛宏斌, 等. 玉米秸秆炭和典型农业废弃物混合成型与燃烧特性试验[J]. 农业工程学报, 2020, 36(15):227-234. XIE T, WANG Y J, CONG H B, et al. Experiment on combustion characteristic and densified biomass pellets from maize stalk char mixing typical agricultural wastes[J]. Transactions of the Chinese Society of Agricultural Engineering, 2020, 36(15):227-234. (in Chinese) [4] 刘佳政, 牛文娟, 钟菲, 等. 不同类型秸秆生物炭的燃烧特性与动力学分析[J]. 太阳能学报, 2019, 40(6):1647-1655. LIU J Z, NIU W J, ZHONG F, et al. Combustion characteristics and kinetic analysis of different types of crop residue biochars[J]. Acta Energiae Solaris Sinica, 2019, 40(6):1647-1655. (in Chinese) [5] 司耀辉, 陈汉平, 王贤华, 等. 农业秸秆燃烧特性及动力学分析[J]. 华中科技大学学报(自然科学版), 2012, 40(1):128-132. SI Y H, CHEN H P, WANG X H, et al. Combustion characteristics and kinetic analysis of agricultural straw[J]. Journal of Huazhong University of Science and Technology (Natural Science Edition), 2012, 40(1):128-132. (in Chinese) [6] 吕薇, 李彦栋, 柳建华, 等. 生物质秸秆燃烧动力学特性分析[J]. 哈尔滨理工大学学报, 2010, 15(5):129-131. LÜ W, LI Y D, LIU J H, et al. Combustion kinetics property analysis of biomass stalk[J]. Journal of Harbin University of Science and Technology, 2010, 15(5):129-131. (in Chinese) [7] 田松峰, 罗伟光, 荆有印, 等. 玉米秸秆燃烧过程及燃烧动力学分析[J]. 太阳能学报, 2008, 29(12):1569-1572. TIAN S F, LUO W G, JING Y Y, et al. Analysis of corn straw combustion process and combustion dynamics[J]. Acta Energiae Solaris Sinica, 2008, 29(12):1569-1572. (in Chinese) [8] 田松峰, 薛海亮, 付小倩, 等. 玉米秸秆燃烧特性的实验分析[J]. 电站系统工程, 2008, 24(1):21-23. TIAN S F, XUE H L, FU X Q, et al. Combustion characteristics experimental analysis of cornstalk[J]. Power System Engineering, 2008, 24(1):21-23. (in Chinese) [9] 刘郁珏, 张涵斌, 张歆然. 秸秆热解·燃烧特性及动力学研究[J]. 安徽农业科学, 2019, 47(4):12-17, 21. LIU Y J, ZHANG H B, ZHANG X R. Study on dynamics and character of straw pyrogenic decomposition and combustion[J]. Journal of Anhui Agricultural Sciences, 2019, 47(4):12-17, 21. (in Chinese) [10] 冯瑞, 田润和, 陈科位, 等. 低气压环境对固体燃烧特性影响的实验研究[J]. 清华大学学报(自然科学版), 2019, 59(2):111-121. FENG R, TIAN R H, CHEN K W, et al. Experimental study of the effect of low pressures on solid fuel combustion characteristics[J]. Journal of Tsinghua University (Science and Technology), 2019, 59(2):111-121. (in Chinese) [11] 石美, 韦善阳, 高布桐. 相邻木结构建筑火灾蔓延临界值研究[J]. 中国安全生产科学技术, 2021, 17(5):149-154. SHI M, WEI S Y, GAO B T. Study on critical value of fire spread in adjacent wooden structure buildings[J]. Journal of Safety Science and Technology, 2021, 17(5):149-154. (in Chinese) [12] 刘长春, 刘新磊, 周莎莎, 等. 火焰脉动在火灾领域相关研究进展[J]. 中国安全生产科学技术, 2018, 14(3):48-56. LIU C C, LIU X L, ZHOU S S, et al. Research progress on flame pulsation in fire field[J]. Journal of Safety Science and Technology, 2018, 14(3):48-56. (in Chinese) [13] 周洋, 陈飞, 卜蓉伟, 等. 中空结构可燃物竖直向上火蔓延特性实验研究[J]. 中国安全生产科学技术, 2021, 17(8):5-10. ZHOU Y, CHEN F, BU R W, et al. Experimental study on vertical upward flame spread characteristics of combustible with hollow structure[J]. Journal of Safety Science and Technology, 2021, 17(8):5-10. (in Chinese) [14] 庄文昌, 闫繁华, 王欲晓. 氧弹式量热法测定农业秸秆的燃烧热[J]. 科教导刊, 2014(4):187-188. ZHUANG W C, YAN F H, WANG Y X. Oxygen bomb calorimetry to measure combustion heat of agricultural straw[J]. The Guide of Science & Education, 2014(4):187-188. (in Chinese) [15] LIU J H, ZHOU Z H, CHEN M Y. Experimental investigation on the effect of ambient pressure on entrainment coefficient of pool fires[J]. Applied Thermal Engineering, 2019, 148:939-943. [16] WANG C J, GUO J, DING Y M, et al. Burning rate of merged pool fire on the hollow square tray[J]. Journal of Hazardous Materials, 2015, 290:78-86. [17] LI C, YANG R, LI C W, et al. Experimental investigation on the influence of annular pool shape characteristics on n-heptane ring fires[J]. Fire and Materials, 2020, 44(5):640-647. [18] HESKESTAD G. Virtual origins of fire plumes[J]. Fire Safety Journal, 1983, 5(2):109-114. [19] KONG D P, HE X, YANG H B, et al. Experimental study for flame base drag and burning efficiency of spilled crude oil during in-situ burning on water[J]. Process Safety and Environmental Protection, 2019, 131:48-54. [20] ZHAO Y L, CHEN J, CHEN X, et al. Influence of high atmospheric pressure on flame spread over electric wire at different inclinations[J]. Process Safety and Environmental Protection, 2020, 136:66-75. |
|
Viewed |
|
|
|
Full text
|
|
|
|
|
Abstract
|
|
|
|
|
Cited |
|
|
|
|
|
Shared |
|
|
|
|
|
Discussed |
|
|
|
|