Effects of gas volume fraction on venting features of 90° elbows after explosion

doi:10.16265/j.cnki.issn 1003-3033.2020.11.015

Abstract

Abstract: In order to explore propagation characteristics of gas with different volume fractions in explosion chambers and venting characteristics of 90° elbows, a gas venting experiment was carried out. Numerical simulation and experimental research were used to analyze propagation process of explosive blast in system, and variation characteristics of blast and flame size of six groups of gas at different volume fraction were explored. The results show that propagation of explosion shock wave in pipeline is in the form of multiple overpressure, and its peak overpressure gradually decreases. Additionally, peak overpressure and its rising rate in explosion cavity have the same change trend, and both reach maximum when gas volume fraction is 9.5%. At the same position in 90°elbows, peak overpressure rising rate generated by different volume fractions of gas is in a sawtooth shape. When it is 5.8%-11.0%, flame size varies in a sawtooth shape along with propagation distance. When at 5.8% and 6.5%, flame is extinguished before 90°. When between 5.8% and 11%, peak overpressure and flame size are significantly attenuated after pipe is bent at 90°

Key words: gas volume fraction, 90° elbow, shock wave, flame size, venting features, numerical simulation

CLC Number:

X932

HUANG Qiang, MU Chaomin, WANG Yajun, ZHOU Hui, LI Zhongqing. Effects of gas volume fraction on venting features of 90° elbows after explosion[J]. China Safety Science Journal, 2020, 30(11): 101-107.

References

[1] 徐景德. 矿井瓦斯爆炸冲击波传播规律及影响因素的研究[D]. 北京:中国矿业大学(北京),2003.
XU Jingde.The study on gas explosion wave propagation law and affected factors in mine [D]. Beijing: China University of Mining and Technology(Beijing), 2003.
[2] 侯万兵,谭迎新,张英浩.模拟煤矿巷道内瓦斯爆炸特性的试验研究[J].煤炭科学技术,2009,37(5): 58-61.
HOU Wanbing,TAN Yingxin,ZHANG Yinghao.Experimental study on gas explosion features in simulated mine roadway [J]. Coal Science and Technology,2009,37(5): 58-61.
[3] 高娜,张延松,胡毅亭.温度压力对瓦斯爆炸危险性影响的实验研究[J].爆炸与冲击,2016,36(2): 218-223.
GAO Na, ZHANG Yansong, HU Yiting.Experimental study on gas explosion hazard under different temperatures and pressures [J].Explosion and Shock Waves, 2016,36 (2): 218-223.
[4] 姜孝海. 泄爆外流场的动力学机理研究[D].南京:南京理工大学,2004.
JIANG Xiaohai. Study on dynamic of the external flowfield during venting [D]. Nanjing: Nanjing University of Science and Technology, 2004.
[5] ANDREWS G E, PHYLAKTOU H N. Experimental study on vented gas explosion in a cylindrical vessel with a vent duct [J]. Process Safety and Environmental Protection, 2013, 91 (4): 245-252.
[6] TOMLIN G, JOHNSON D M, CRONIN P, et al. The effect of vent size and congestion in large-scale vented natural gas/air explosions[J]. Journal of Loss Prevention in the Process Industries, 2015, 35: 169 -181.
[7] 王世茂,杜扬,李国庆,等.含弱约束受限空间油气爆炸外部特性研究[J].振动与冲击,2017,36(15): 253-258.
WANG Shimao, DU Yang, LI Guoqing, et al. Tests for external explosion characteristics of fuel-air mixture in a confined space with weak constraint surfaces [J].Journal of Vibration and Shock,2017,36(15): 253-258.
[8] 田诗雅,刘剑,高科.密闭管道瓦斯爆炸冲击波冲量及压力上升速率的试验研究[J].中国安全生产科学技术,2015,11(8): 16-21.
TIAN Shiya, LIU Jian, GAO Ke.Experimental study on shock wave impulse and pressure rise rate of gas explosion in airtight pipeline [J]. Journal of Safety Science and Technology, 2015,11 (8): 16-21.
[9] 李昂,司俊鸿,周西华,等.大直径瓦斯管道泄爆门泄爆特性试验研究[J].中国安全科学学报,2019,29(11): 109-115.
LI Ang, SI Junhong, ZHOU Xihua, et al. Experimentalresearch on the explosion characteristics of large diameter gas pipeline explosion gate [J]. China Safety Science Journal, 2019,29 (11): 109-115.
[10] WANG Cheng,ZHAO Yongyao,EMMANUEL K A. Investigation on propagation mechanism of large scale mine gas explosions[J]. Journal of Loss Prevention in the Process Industries,2017,49: 342-347.
[11] 洪溢都,林柏泉,朱传杰.开口型管道内瓦斯爆炸冲击波动压的数值模拟[J].爆炸与冲击,2016,36(2): 198-209.
HONG Yidu,LIN Baiquan,ZHU Chuanjie. Simulation on dynamic pressure of premixed methane/air explosion in open-end pipes [J].Explosion and Shock Waves,2016,36(2): 198-209.
[12] 曲志明,周心权,王海燕,等.瓦斯爆炸冲击波超压的衰减规律[J].煤炭学报,2008(4): 410-414.
QU Zhiming, ZHOU Xinquan, WANG Haiyan,et al. Overpressure attenuation of shock wave during gas explosion [J].Journal of China Coal Society,2008(4): 410-414.
[13] 刘如成,朱云飞.煤矿长壁工作面瓦斯爆炸全尺寸模拟[J].中国安全科学学报,2018,28(12): 58-64.
LIU Rucheng, ZHU Yunfei. Full-scale simulation of gas explosion at longwall coalface in coalmine [J]. China Safety Science Journal, 2018,28 (12): 58-64.
[14] 邱进伟. 瓦斯爆炸冲击波在管网内传播特征及灾变过程仿真研究[D].淮南:安徽理工大学,2018.
QIU Jinwei. Study on propagation characteristics of shock wave in pipe network and simulation of catastrophic process for gas explosion [D]. Huainan:Anhui University of Science and Technology, 2018.
[15] 周辉,穆朝民,刘伟,等.空腔体长度对抑制瓦斯爆炸性能的影响研究[J].中国安全科学学报,2019,29(9): 107-112.
ZHOU Hui, MU Chaomin, LIU Wei, et al. Influence of cavity length on gas explosion suppression [J]. China Safety Science Journal, 2019,29 (9): 107-112.