摘要
狭长受限空间由于结构的约束性,发生气体爆炸时易导致严重的爆炸后果。甲烷是瓦斯和天然气的主要成分,煤矿巷道和地下管涵等狭长受限空间的甲烷-空气爆炸严重威胁工业生产安全。本文系统分析了国内外狭长受限空间甲烷-空气爆炸事故研究成果,按气体体积比和气体体积、环境因素、点火源、障碍物、结构等影响因素分类评述了当前的研究进展,指出各因素下甲烷-空气爆炸后果影响研究中存在的不足,提出爆炸特征参数演化以定性为主向定量化表征是未来研究的重点,对数值模拟软件进行二次开发以实现爆炸流场演化导致结构变形的全过程分析是进一步完善的方向,对狭长受限空间甲烷-空气爆炸事故防控和后果评估具有一定指导价值。
The paper is aimed at making a research advance review in the methane-air explosion propagating regularity and the consequential outcomes in the narrow confined space. As a matter of fact,the so-called narrow confined space used to enjoy the characteristic features of the great proportional sphere ratio in the somewhat considerable restriction extents and therefore may lead to serious consequences if a gas explosion takes place instantly.The severity of such sorts of explosion should also be dependent on the other numerous influential factors,which may push us to trace and determine the propagative regularities of the gas explosion with some other critical influential factors taken into account and discussion. For instance,just like such gas content rate,the stoichiometric content rate may also lead to the most serious explosion consequences,whereas for the vented explosion, the content rates even slightly higher than the stoichiometric concentration may lead to a bit stronger or more intensive explosion,whose flame zone and length can be taken to characterize the effect of the gas volume on the explosion consequences. And,in turn,the length of the flame zone would be likely to increase exponentially with the increase of the premixed gas volume. In addition,in terms of the environmental factors,the initial pressure can also be correlated positively with the explosion severity,which may suggest that therein lies a " competitive mechanism" for the effects of the initial temperature on the explosion. Besides,the characteristic features of the ignition source may also enact a vital role on the explosion process. On the other hand,the minimum ignition energy (short for MIE) tends to increase with the decrease of the initial temperature or pressure. The influence of the ignition position on the explosion severity is actually influenced by the aspect ratio of the structure,the volume of the explosion chamber and the ventilation conditions. And,the influence of the obstacles on the explosion consequences can be divided into 5 aspects,that is,the shape,the quantity,the blockage rate,the position,and the spacing. All these 5 factors may have different excitation effects on the explosion process due to their impact on the laminar and turbulent combustion. In terms of the spatial structure,it should not ignore the size and shape features of the structure whereas the influence of the wall roughness of the structure can be found affecting the explosion consequences with a double effect. On the one hand,it promotes the turbulence,and,then,it may cause an energy loss,to promote or suppress the explosion consequences,which may depend on which one is dominant. And,finally,the problems involving the current research and the prospect involved have also been mentioned. That is,first of all,there exist shortcomings in the study of the explosion propagation regularity under the various influential factors;Secondly,the quantification of the explosion characteristic parameters needs to be deepened,and the quantitative characterization model of the explosion characteristic parameters should be established in combination with the similarity theory and revised continuously through massive experiments.And,thirdly,the numerical simulation method may not be perfect,for the simulation of the explosion flow field is actually separate from the dynamic response of the structure,so it is necessary to develop a simulation software to realize the interaction between the fluid and the solid structure in the explosion process.
作者
陈国华
董浩宇
张强
赵一新
胡盛
李少鹏
CHEN Guo-hua;DONG Hao-yu;ZHANG Qiang;ZHAO Yi-xin;HU Sheng;LI Shao-peng(Institute of Safety Science&Engineering,South China University of Technology,Guangzhou 510641,China)
出处
《安全与环境学报》
CAS
CSCD
北大核心
2020年第3期946-959,共14页
Journal of Safety and Environment
基金
国家重点研发计划项目(2017YFC0804700)
广东省省级科技计划项目(2017A020219010)。
关键词
安全工程
狭长受限空间
甲烷-空气爆炸
传播规律
事故后果
safety engineering
narrow confined space
methaneair explosion
propagation law
accident consequence
