邻近电力管道的城市埋地燃气管道泄漏扩散数值模拟研究

Numerical simulation study on leakage and diffusion of urban buried gas pipeline adjacent to electric pipeline

为进一步预防城市埋地燃气管道与电力管道耦合事故发生,基于邻近电力管道的埋地燃气管道物理模型,采用Fluent软件对甲烷燃气泄漏扩散进行三维数值模拟分析,研究城市埋地燃气管道与电力管道耦合场景下的燃气泄漏扩散行为。研究结果表明:甲烷燃气扩散速率受土壤类型的影响较大,相比壤土和黏土,甲烷燃气在砂土中扩散速率相对最快;甲烷燃气扩散范围随着管道压力的增大而增大,需重点关注泄漏孔附近区域尤其是上方高浓度区;甲烷燃气发生泄漏后在电力井内迅速扩散,最快会在34 s内达到预警浓度,并在70 s左后时达到爆炸极限范围。研究结果可为城市埋地燃气管道与电力管道耦合场景下的风险监测预警提供决策参考。

To prevent the occurrence of coupling accidents of urban buried gas pipeline and electric pipeline,based on the physical model of buried gas pipeline adjacent to electric pipeline,the Fluent software was utilized to carry out three-dimensional numerical simulation analysis of its leakage and diffusion,and the gas leakage and diffusion behavior in the coupling scenario of urban buried gas pipeline and electric pipeline was studied.The results show that the gas diffusion rate is greatly affected by the soil type,in which the diffusion rate is relatively the fastest in sandy soil.The diffusion range increases with the increase of pipeline pressure,and it is necessary to pay attention to the area near the leakage hole,especially the high concentration area above.The leaking gas diffuses rapidly in the electric wells,then reaches the warning concentration in 34 s at the earliest,and rapidly reaches the explosion limit range at 70 s.The research results can provide decision-making reference for the risk monitoring and early-warning in the coupling scenario of urban buried gas pipeline and electric pipeline.