Simulation study on gas explosion induced by gas leakage of urban buried gas pipelines

doi:10.16265/j.cnki.issn1003-3033.2021.09.011

Abstract

Abstract: In order to explore overpressure and temperature characteristics of explosion flow field after gas leakage of buried natural gas pipelines, FLACS was used to simulate leakage and explosion accidents of pipelines. Then, development characteristics of these accidents were studied from three aspects, environmental wind speed, leak rate, and leakage aperture. The results show that under a condition of continuous and stable leakage, flammable gas's coverage area will be stable. Wind speed, leakage aperture and leak rate influences buoyancy dispersion stage, jet nucleus, and initial momentum respectively, thus influencing gas dispersion. When an accident happens, explosion flame mainly propagates upward, and the overpressure it generates is comparatively small, but the temperature is high. Under windless condition, when leakage aperture is 0.3 m, leak rate at 4 kg/s, overpressure of gas cloud explosion generated by leakage is 0.46 kPa, while high temperature generated reaches as high as 2 135.7 K.

Key words: buried natural gas pipeline, pipeline leakage, gas cloud explosion, FLACS software, simulation analysis

CLC Number:

X932

WANG Qiuhong, WANG Liwen, JIANG Juncheng, ZHANG Mingguang, LI Xin. Simulation study on gas explosion induced by gas leakage of urban buried gas pipelines[J]. China Safety Science Journal, 2021, 31(9): 75-82.

References

[1] LI Xiaojian, ZHOU Ruiping, KONOVESSIS D. CFD analysis of natural gas dispersion in engine room space based on multi-factor coupling[J]. Ocean Engineering, 2016,111:524-532.
[2] MISHRA K B, WEHRSTEDT K D. Underground gas pipeline explosion and fire: CFD based assessment of foreseeability[J].Journal of Natural Gas Science & Engineering, 2015,24:526-542.
[3] LIU Aihua, HUANG Jian, LI Zhiwen, et al. Numerical simulation and experiment on the law of urban natural gas leakage and diffusion for different building layouts[J]. Journal of Natural Gas Science & Engineering,2018,54: 1-10.
[4] 李朝阳, 马贵阳, 徐柳. 架空及埋地天然气管道泄漏扩散数值研究[J]. 中国安全生产科学技术, 2011,7(7):66-69.
LI Chaoyang, MA Guiyang, XU Liu. Numerical study on the diffusion concentration of overhead and buried natural gas pipeline[J]. Journal of Safety Science and Technology, 2011,7(7):66-69.
[5] 王赟, 李晓青, 孙建宇, 等. 基于Fluent的坡面天然气管道破裂泄漏扩散模拟[J]. 中国安全生产科学技术, 2014, 10(增1): 89-93.
WANG Yun, LI Xiaoqing, SUN Jianyu, et al. Simulation study on leakage and dispersion of ruptured natural gas pipeline on the slope with FLUENT CFD-based software[J]. Journal of Safety Science and Technology, 2014,10(S1): 89-93.
[6] 杨石刚, 方秦, 张亚栋, 等. 非均匀混合可燃气云爆炸的数值计算方法[J]. 天然气工业, 2014,34(6):155-161.
YANG Shigang, FANG Qin, ZHANG Yadong, et al. A numerical method of calculating the consequence of heterogeneous mixed vapor cloud explosion[J]. Natural Gas Industry, 2014,34(6):155-161.
[7] 李云涛, 张振永, 刘玉卿, 等. 天然气管道全管径断裂事故影响范围研究[J]. 中国安全科学学报, 2020,30(9):149-154.
LI Yuntao, ZHANG Zhenyong, LIU Yuqing, et al. Influence range of full bore rupture accidents of natural gas pipelines[J].China Safety Science Journal, 2020,30(9):149-154.
[8] 黄有波, 董炳燕, 吕淑然,等. 天然气管道泄漏孔形状对喷射火影响模拟研究[J]. 中国安全科学学报, 2015,25(7):62-67.
HUANG Youbo, DONG Bingyan, LYU Shuran, et al. Simulation study on influence of natural gas pipeline leak hole shape on jet fire[J]. China Safety Science Journal, 2015,25(7):62-67.
[9] 王向阳, 杜美萍, 汪彤, 等.埋地燃气管道泄漏扩散过程数值模拟[J]. 中国安全科学学报, 2018,28(2):45-50.
WANG Xiangyang, DU Meiping, WANG Tong, et al. Numerical simulation of leakage of gas from buried pipeline and its diffusion process[J]. China Safety Science Journal, 2018,28(2):45-50.
[10] HANSEN O R, GAVELLI F, ICHARD M, et al. Validation of FLACS against experimental data sets from the model evaluation database for LNG vapor dispersion[J]. Journal of Loss Prevention in the Process Industries, 2010,23(6):857-877.
[11] MIDDHA P, ICHARD M, ARNTZEN B J. Validation of CFD modelling of LH₂spread and evaporation against large-scale spill experiments[J]. International Journal of Hydrogen Energy, 2011,36(3):2 620-2 627.
[12] 文虎, 高慧慧, 王秋红, 等. 泄爆口强度对管内天然气爆炸流场的影响仿真[J]. 天然气工业, 2019,39(8):126-136.
WEN Hu, GAO Huihui, WANG Qiuhong, et al. A simulation study on the influence of vent port strength on the natural gas explosion flow field in line pipes[J]. Natural Gas Industry, 2019,39(8):126-136.
[13] 王秋红, 孙艺林, 李鑫, 等. 乙烯储罐气体泄漏诱发蒸气云爆炸的数值模拟[J]. 爆炸与冲击, 2020, 40(12): 121-133.
WANG Qiuhong, SUN Yilin, LI Xin, et al. Numerical simulation of gas dispersions and vapor cloud explosions induced by released gas from an ethylene storage tank[J]. Explosion and Shock Waves, 2020, 40(12): 121-133.
[14] WANG Qiuhong, SUN Yilin, SHU Chimin, et al. Effect of separation distance on gas dispersion and vapor cloud explosion in a storage tank farm determined using computational fluid dynamics[J]. Journal of Loss Prevention in the Process Industries, 2020, 68:DOI: 10.1016/J.JLP.2020.104282.
[15] 王志寰, 李成兵, 周宁. 大型LNG接收站泄漏事故灾害效应分析与预测[J]. 天然气工业, 2019,39(5):145-153.
WANG Zhihuan, LI Chengbing, ZHOU Ning. Analysis and prediction on the disaster effect of leakage accidents at large LNG receiving stations[J]. Natural Gas Industry, 2019,39(5): 145-153.
[16] SCHLEDER A M, MARTINS M R. Experimental data and CFD performance for CO₂ cloud dispersion analysis[J]. Journal of Loss Prevention in the Process Industries, 2016,43: 688-699.
[17] FIATES J, SANTOS R, NETO F F, et al. An alternative CFD tool for gas dispersion modelling of heavy gas[J]. Journal of Loss Prevention in the Process Industries, 2016, 44: 583-593.
[18] DASGOTRA A, TEJA G, SHARMA A, et al. CFD modeling of large-scale flammable cloud dispersion using FLACS[J]. Journal of Loss Prevention in the Process Industries, 2018, 56: 531-536.
[19] 徐景德, 李晖, 郝旭. FLACS在受限空间可燃气体爆炸传播研究中的应用[J]. 华北科技学院学报, 2016,13(3):7-11.
XU Jingde, LI Hui, HAO Xu. Application of FLACS in the study of numerical simulation of gas explosion in confined space[J]. Journal of North China Institute of Science and Technology, 2016,13(3):7-11.
[20] 李炜, 槐文信. 浮力射流的理论及应用[M]. 北京: 科学出版社, 1997: 2-5.
[21] 罗正鸿, 詹晓力, 丁信伟, 等. 小气量开敞空间可燃气云爆燃实验[J]. 浙江大学学报, 2002, 36(1): 105-108.
LUO Zhenghong, ZHAN Xiaoli, DING Xinwei, et al. Experimental investigation into deflagration of small-volume combustible vapour clouds[J]. Journal of Zhejiang University, 2002, 36(1): 105-108.
[22] 任少云. 开敞空间液化天然气泄漏低温扩散及爆炸传播规律[J]. 爆炸与冲击, 2018, 38(4): 891-897.
REN Shaoyun. The leakage, low temperature diffusion and explosion of liquefied natural gas in open space[J]. Explosion and Shock Waves, 2018,38(4):891-897.