摘要
为研究厨房内天然气泄漏的体积分数分布演化规律,为现场应急救援提供理论指导,采用Fluent模拟了厨房内天然气泄漏扩散过程,分析了天然气扩散迹线、体积分数分布状况。结果表明,不同泄漏情况下天然气初始速度大于1 m/s,天然气稳定状态下燃气灶处、厨房上部空间聚集形成厚度0.5 m以上的高体积分数天然气-空气预混层、门缝附近距地面高度1.5 m以上为厨房空间3处超过爆炸下限5%的区域,而燃气灶、顶灯及顶灯开关3处较易出现明火或电火花,形成了爆炸危害大与易爆区域位置重合的情况,极大地提高了天然气泄漏的危险性。最后对燃气软管脱落泄漏情况下天然气厨房内体积分数进行了试验测定,试验与模拟相对误差小于10%,验证了模拟的厨房内天然气泄漏扩散规律是较准确的。
Compared with traditional energy sources,efficient and clean natural gas has obvious advantages.Natural gas has developed rapidly under the influence of environmental protection and other factors.Since natural gas may leak with a risk of explosion,it is necessary to study the law of natural gas leakage and diffusion.To grasp the evolution law of the volume fraction distribution of indoor natural gas leakage and provide theoretical guidance for on-site emergency rescue,Fluent was used to simulate the diffusion process of indoor natural gas leakage,and the distribution of natural gas diffusion traces and volume fraction distribution were analyzed.The results show that the stove cabinet has a certain restrictive effect on the leakage and diffusion of natural gas.The diffusion state of natural gas in the stove cabinet is disordered,and the diffusion state of natural gas that flows into the room through the gap of the stove cabinet is relatively stable,mainly spreading towards the top.In the case of natural gas leakage where the leakage source is located indoors,natural gas first mainly manifests as a lateral jet movement.With the increase of the distance from the leakage source,the cross-sectional area of the jet expands,the expansion and diffusion speed in the vertical direction increases,and the diffusion trace rose.In the steady-state of natural gas leakage and diffusion,the gas stove,the high volume fraction natural gas-air premixed layer formed by the accumulation of natural gas in the upper indoor space,and the height of 1.5 m above the ground near the door gap are three areas in the indoor space that exceed the lower explosion limit.The gas stove,ceiling light,and ceiling light switch are prone to open flames or electric sparks,leading to the overlap of the explosive area and the explosion hazard area overlap and increasing the risk of natural gas leakage.Finally,by testing the volume fraction of natural gas in the room when the gas hose falls off and leaks,it is verified that the simulated indoor natural gas
作者
汪建平
段卫东
李春青
史立军
马长城
荆亚州
WANG Jian-ping;DUAN Wei-dong;LI Chun-qing;SHI Li-jun;MA Chang-cheng;JING Ya-zhou(Beijing Gas Group Company Limited,Beijing 100035,China)
出处
《安全与环境学报》
CAS
CSCD
北大核心
2022年第1期298-305,共8页
Journal of Safety and Environment
关键词
安全工程
天然气
泄漏扩散
数值模拟
试验验证
safety engineering
natural gas
leakage and diffusion
numerical simulation
experimental verification
