摘要
油气管线在城市地下组成了密集的管网,并与地下暗渠、电缆沟等市政管涵地下密闭空间相邻或交叉。在燃气通过管线输送的过程中,由于泄漏而进入密闭空间并引起爆炸的事故时有发生且往往会导致较为严重的后果。为此,借助LS—DYNA非线性动力分析有限元软件,基于流固耦合与ALE多物质算法,建立密闭空间下燃气爆炸数值计算模型,探究了密闭空间燃气爆炸过程中爆炸冲击波的传播与衰减变化规律。数值计算结果表明:与将爆炸假设为理想点源爆炸不同,在密闭空间结构环境的限制作用下,爆炸冲击波最初以椭球状形式分布,在传播过程中逐渐向球状冲击波发展,并迅速衰减,最终在大气环境中沿密闭空间宽度方向上传播距离最远。根据爆炸冲击波超压幅值对人体的影响程度划分不同的伤亡等级,拟合数值计算结果得到了密闭空间爆炸冲击波传播衰减计算公式,据此可以准确划分密闭空间爆炸事故后果不同伤亡等级区域范围。
Urban oil ＆ gas pipelines cross over and adjoin to culverts, cable trenches, etc. underground in such a confined space that ex-plosion accidents are liable to happen if gas leakage occurs during pipeline transportation, rather serious consequences will be caused. In view of this, the non-linear numerical simulation finite element software LS-DYNA was applied to establish a confined space explosion FEM model by use of the fluid-solid coupling and multi-material ALE algorithm. On this basis, the propagation and attenuation charac~ teristics of explosion shock waves were discussed. Analysis results show that, unlike the supposed ideal point-source explosion, the shock waves resulting from a confined space explosion were presented in an ellipsoidal distribution at first. Then, during their propagation pro- cess, those waves become attenuated gradually in a spherical distribution and fade into nothingness along the outlet. Finally, according to the overpressure amplitudes of the shock waves, the casualty ranking criteria about people subjected to explosion shock waves were established. Based on the numerical analysis, the formulae were obtained to calculate the explosion shock waves propagation and attenua- tion, upon which various area coverage was thus accurately divided by different casualty ranking levels.
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2017年第2期120-125,共6页
Natural Gas Industry
基金
国家自然科学基金项目(编号:21576102)
广东省安全生产专项资金项目(编号:2014-89)
关键词
城市地下管网
密闭空间
爆炸数值计算
流固耦合
爆炸冲击波
超压幅值
传播规律
伤亡区域划分
伤亡后果
评价
Urban underground pipeline
Confined space
Explosion numerical simulation
Fluid-solid coupling, Explosion shock wave
Overpressure amplitude, Propagation law
Casualty zone division, Casualty assessment
