Abstract To initiate the experimental study of natural gas diffusion in sewage pipeline and evaluate the sewage pipeline risk, a new outdoor full-scale water cycling experimental pipeline system was built. The concentration distributions and characteristic time were measured in a comprehensive monitoring system. As the rate of the gas leakage flow decreases, the alarm time increases significantly. It is found that the influence of water flow direction on methane gas diffusion is different under varying gas flow rates. Furthermore, the methane diffusion rate in sewage pipeline is also a function of water flow rate and water level height. Based on the experimental results, the corresponding suggestions for prevention and control of gas leakage accidents in sewage pipelines were put forward to improve the urban public security management system and the security capacity of urban public security.

中文翻译：

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新型户外全尺寸水循环实验管道系统对污水管道天然气扩散行为的研究

摘要 为开展天然气在污水管道中扩散的实验研究，评估污水管道的风险，构建了新型户外全尺度水循环实验管道系统。在综合监测系统中测量浓度分布和特征时间。随着气体泄漏流量的降低，报警时间显着增加。发现在不同的气体流速下，水流方向对甲烷气体扩散的影响是不同的。此外，污水管道中的甲烷扩散速率也是水流量和水位高度的函数。根据实验结果，