Effects of a T-shaped branch pipe on overpressureof gasoline-air mixture explosion
-
摘要: 为了研究T型分支结构对管道内油气爆炸压力的影响，进行了不同初始油气体积分数、不同初始点火能工况下多参数对比实验，并对火焰传播进行了可视化研究。实验结果表明：T型分支管道对油气爆炸压力有强化作用，强化程度和初始油气体积分数关系密切，在当量比附近，强化程度表现最显著；初始点火能对油气爆炸最大超压影响显著，随着点火能的增大，最大爆炸超压呈线性增长；波的绕射和反射、流场湍流度增强、管道通道面积增大和障碍物扰动是导致T型分支管道内爆炸压力增强的主要因素；T型分支管道会导致火焰阵面严重地弯曲褶皱变形，增大火焰面积，并且回传火焰对T型分支结构壁面具有较强的破坏作用。Abstract: To investigate the effects of a T-shaped branch structure on the overpressures during the explosions of the gasoline-air mixture in a pipe, we conducted multiple parameter contrast experiments under the conditions of different initial gasoline vaper volume fractions and different initial ignition energy, and carried out visualized investigation on the flame propagation of the mixture. Our research reveal the following results: the T-shaped branch pipe can enhance the explosive overpressure of the gasoline-air mixture in a pipe, and the degree of this enhancement is closely related with the increase of the initial gasoline vaper volume fraction approximately in a parabolic trend, and with the maximum value obtained around the stoichiometric initial concentration. The maximum explosive overpressures before and after the T-shaped branch pipe increases linearly with the growth of the initial ignition energy. The effects of the T-shaped branch pipe on raising the degree of the explosion mainly originate from four factors: the wave diffraction and reflection, the turbulence enhancement, the sudden expansion of the pipe cross-section area and the reinforcement of the disturbance by the obstacles. It can be seen from the visual analysis that, when the flame propagates through the T-shaped branch pipe, the flame front is distorted seriously into creases, the flame surface area is enlarged, and the returning flames are observed, which exerts a destructive effect on the wall of the T-shaped branch pipe.
-
Key words:
- T-shaped branch pipe /
- gasoline-air mixture /
- explosion wave /
- visualization
-
图 3 不同初始点火能下油气起爆过程
Figure 3. Initial explosion progress of gasoline vaper at different initial igintion energies
图 5 两对比实验中爆炸超压随时间和空间的变化
Figure 5. Explosion overpressure varying with time and space in two contrast experiments
图 6 两对比实验测点1、2最大爆炸压力随初始油气体积分数的变化
Figure 6. Maximum explosion pressure of measuring points 1 and 2 within two contrast experiments at different initial gasoline vaper volume fractions
图 7 不同初始油气体积分数下的压力强化因数
Figure 7. Enhancement coefficient of pressureat different initial gasoline vaper volume fractions
图 8 3种不同初始油气体积分数条件下测点1、2压力峰值随初始点火能变化关系
Figure 8. Peak overpressure of two measuring points varying with initial ignition energy at three different initial gasoline vaper volume fractions
图 9 火焰传播经过T型分支管道时的形态变化过程
Figure 9. Morphological changes of flame when propagating through T-shaped branch pipe
-
[1] 王世茂, 杜扬, 张少波, 等.顶部开口条件下油罐油气爆炸数值模拟[J].后勤工程学院学报, 2015, 31(4):52-56. http://d.old.wanfangdata.com.cn/Periodical/hqgcxyxb201504009Wang Shimao, Du Yang, Zhang Shaobo, et al.Numerical simulation on fuel-air mixture explosion in the oil tank with an open top[J].Journal of Logistical Engineering University, 2015, 31(4):52-56. http://d.old.wanfangdata.com.cn/Periodical/hqgcxyxb201504009 [2] Park D J, Lee Y S, Green A R.Experiments on the effects of multiple obstacles in vented explosion chambers[J].Journal of Hazardous Materials, 2008, 153(1/2):340-350. http://www.sciencedirect.com/science/article/pii/S0304389407012307 [3] Blanchard R, Arndt D, Grätz R, et al.Explosions in closed pipes containing baffles and 90 degree bends[J].Journal of Loss Prevention in the Process Industries, 2010, 23(2):253-259. doi: 10.1016/j.jlp.2009.09.004 [4] Zhang Peili, Du Yang, Zhou Yi, et al.Explosions of gasoline-air mixture in the tunnels containing branch configuration[J].Journal of Loss Prevention in the Process Industries, 2013, 26(6):1279-1284. doi: 10.1016/j.jlp.2013.07.003 [5] Vasil'ev A A, Trotsyuk A V.Experimental investigation and numerical simulation of an expanding multiform detonation wave[J].Combustion, Explosion, and Shock Waves, 2003, 39(1):80-90. doi: 10.1023/A:1022157504636 [6] Thomas G, Oakley G, Bambrey R.An experimental study of flame acceleration and deflagration to detonation transition in representative process piping[J].Process Safety and Environmental Protection, 2010, 88(2):75-90. doi: 10.1016/j.psep.2009.11.008 [7] Ciccarelli G, Dorofeev S.Flame acceleration and transition to detonation in ducts[J].Progress in Energy and Combustion Science, 2008, 34(4):499-550. doi: 10.1016/j.pecs.2007.11.002 [8] 顾金龙, 翟成.爆炸性气体在连续拐弯管道中传播特性的实验研究[J].火灾科学, 2011, 20(1):16-20. doi: 10.3969/j.issn.1004-5309.2011.01.003Gu jinlong, Zhai Cheng.Gas explosion propagation characteritics in continuous turning pipe[J].Fire Safety Science, 2011, 20(1):16-20. doi: 10.3969/j.issn.1004-5309.2011.01.003 [9] 林柏泉, 叶青, 翟成, 等.瓦斯爆炸在分岔管道中的传播规律及分析[J].煤炭学报, 2008, 33(2):136-139. doi: 10.3321/j.issn:0253-9993.2008.02.004Lin Baiquan, Ye Qing, Zhai Cheng, et al.The propagation rule of methane explosion in bifurcation duct[J].Journal of China Coal Society, 2008, 33(2):136-139. doi: 10.3321/j.issn:0253-9993.2008.02.004 [10] 贾智伟, 景国勋, 程磊, 等.巷道截面积突变情况下瓦斯冲击波传播规律的研究[J].中国安全科学学报, 2007, 17(12):92-94. doi: 10.3969/j.issn.1003-3033.2007.12.016Jia Zhiwei, Jing Guoxun, Cheng Lei, et al.Study on propagation rules about gas explosion shock wave in the laneway with abrupt change of sectional area[J].China Safety Science Journal, 2007, 17(12):92-94. doi: 10.3969/j.issn.1003-3033.2007.12.016 [11] 潘振华, 范宝春, 归明月.T型管内流动气体中爆轰绕射过程的数值模拟[J].爆炸与冲击, 2014, 34(6):709-715. http://www.bzycj.cn/CN/abstract/abstract9406.shtmlPan Zhenhua, Fan Baochun, Gui Mingyue.Numerical investigation on evolution of detonation diffraction in moving gas inside a T-shaped channel[J].Expliosion and Shock Waves, 2014, 34(6):709-715. http://www.bzycj.cn/CN/abstract/abstract9406.shtml [12] Guo Changming, Wang Changjian, Xu Shengli.Cellular pattern evolution in gaseous detonation diffraction in a 90°-branched channel[J].Combustion and Flame, 2007, 148(3):89-99. doi: 10.1016/j.combustflame.2006.11.001 [13] 王昌建, 徐胜利, 郭长铭.气相爆轰波在半圆形弯管中传播现象的实验研究[J].爆炸与冲击, 2003, 23(5):448-453. doi: 10.3321/j.issn:1001-1455.2003.05.011Wang Changjian, Xu Shengli, Guo Changming.Experimental investigation on gaseous detonation propagation through a semi-circle bend tube[J].Expliosion and Shock Waves, 2003, 23(5):448-453. doi: 10.3321/j.issn:1001-1455.2003.05.011 -
下载:
点击查看大图
计量
- 文章访问数: 4160
- HTML全文浏览量: 1216
- PDF下载量: 376
- 被引次数: 0