城市建筑环境下燃气泄漏扩散的数值模拟

Numerical Simulation on Diffusion Law of Gas Pipeline Leakage in Urban Building Environment

为分析泄漏时间、管道压力、泄漏口与建筑物距离三个因素对街道天然气管道泄漏的影响,采用计算流体力学的方法对天然气管道泄漏扩散进行模拟,得到不同影响因素下的甲烷体积分数分布。研究表明:随着泄漏时间的增加,射流高度的增加,气体射流速度逐渐减小,甲烷逐渐向四周扩散;泄漏压力对泄漏的影响较大,直接影响扩散范围;建筑物对甲烷体积分数分布和变化产生很大影响,泄漏天然气对旁边的建筑物有贴附效应。

In order to analyze the effects of three factors:leakage time,pipeline pressure,and the distance between the leak and the building on the street natural gas pipeline leakage,the computational fluid dynamics method was used to simulate the leakage diffusion of natural gas pipelines to obtain the methane volume fraction distribution under different influence factors.The research showed that as the leakage time increases,the jet height increases,the velocity of the gas jet gradually decreases,and the methane diffuses gradually around.Leak pressure has a greater impact on leakage and directly affects diffusion range.Besides,buildings have a great influence on the distribution and change of methane volume fraction,and the leaked natural gas will diffuse upward with the buildings nearby.