城市燃气管道稳态泄漏数值模拟

Numerical simulation of steady state leakage for urban gas pipeline

针对城市燃气管道分布与建筑物距离较近的特点,综合考虑风速、建筑物对燃气管道泄漏后气体分布情况的影响,建立城市燃气管道泄漏模型并对其进行网格划分,利用计算流体力学软件对天然气、人工煤气和液化石油气3种城市燃气的稳态泄漏过程进行数值模拟,考察风速分别为1 m/s和5 m/s情况下,泄漏时间为5 s、20 s、60 s和240 s时3种燃气在建筑物附近的分布情况。结果表明:风速越大,风对燃气向下风向的输送作用越强;燃气易在建筑物周围和街道峡谷内长时间堆积,形成较大危险区域。研究结果可为合理规划城市燃气管网和事故救援提供理论依据。

According to the characteristic that urban gas pipelines are close to buildings, taking the effect of wind speed and building on gas distribution after pipeline leakage into comprehensive consideration, the paper presents an urban gas pipeline leakage model and its grid division, the computational fluid dynamics software is used to make numerical simulation of steady state urban gas pipeline leakage of 3 kinds of urban gas, natural gas, coalbed gas and liquefied petroleum gas, to find out the distribution of the 3 kinds of gas around buildings at the wind speed of 1 m/s and 5 m/s, and leakage time of 5 s, 20 s, 60 s, and 240 s. The results show that the faster the wind is, the stronger the effect of wind on gas blowing downward the wind is, the gas is apt to build up around buildings and narrow streets for a long time, and forms a large dangerous area. The research results can provide theoretical basis to the reasonable planning for urban gas pipeline networks and accident rescue.（7 Figures, 20 References）