管输天然气在不同环境介质中泄漏扩散模拟研究

Simulation Research on the Leakage and Diffusion of Natural Gas Pipeline in Different Environmental Media

为了分析管输天然气在不同介质中泄漏问题,基于流体力学和多孔介质理论,通过CFD软件建立了管道泄漏的三维仿真模型对该问题进行分析。首先,针对架空管道和埋地管道分别建立了泄漏扩散模拟模型和多孔介质的埋地管道模型;其次,对不同压力下的天然气管道进行模拟计算;最后,通过甲烷体积分数和压力分布等参数对管道泄漏现象进行分析。仿真实验结果表明:相同压力下,在空气中泄漏的天然气在进入空气时会形成射流,在同一水平面上沿射流中心点向外甲烷浓度呈抛物线型分布;在土壤中泄漏的天然气会在泄漏口处形成蘑菇云状分布。

In order to analyze the leakage problem in different media,the three-dimensional simulation model of pipeline leakage is established by CFD software based on fluid mechanics and porous media theory.Firstly,the leakage diffusion simulation model and the buried pipe model with porous medium are established respectively for the overhead pipe and the buried pipe;secondly,the natural gas pipeline under different pressures is simulated;finally,the leakage phenomenon is analyzed by the parameters such as methane volume and pressure distribution.The simulation experiment results show that under the same pressure,the natural gas leaking in the air will form a jet when it enters the air.On the same horizontal plane,along the center of the jet,the methane concentration is distributed in parabolic lines.Gas leaking through the soil can form mushroom clouds around the leak.