Abstract: Aiming at the leakage and diffusion problems of the 35 MPa ultrahigh pressure gas pipeline in densely populated area, the FLUENT software in the threedimensional numerical simulation was used under different climate conditions in the deep buried gas pipeline leak case. And the axial and surface safety area of the hydrogen sulfide and methane was provided when the ultrahigh pressure gas pipeline had leaked under the conditions of different wind speeds. Because of the buoyancy, the natural gas developed in the upward form during the process of diffusion. The wind speed and pressure had different effects on the diffusion process under the different environments. The result was that as the wind speed and pressure was higher, the natural gas was spread to the farther distance. This increased the lowest explosive limit and alerted the concentration range of the natural gas. The research result could provide the effective basis to the stuffs and security management in leakage spot.

Key words: Ultrahigh pressure gas, Densely populated area, Leakage；Safe area, ThreeDimensional numerical simulation　

摘要： 针对3 5MP a超高压输气管道在人口密集区域泄漏扩散问题, 采用F LUENT软件, 对不同气候条件
下的埋深天然气管道泄漏情况进行了三维数值模拟, 并给出了超高压天然气在不同风速条件下泄漏后 H2S和CH4
轴向和地表安全区域。在扩散过程中, 天然气在浮力的作用下以向上扩散的形式发展, 在不同的环境下风速和压力
对扩散过程的影响不同, 较大的风速和压力使天然气向更远的距离扩散, 从而增大天然气爆炸下限和警戒浓度范
围。研究结果可为泄漏现场人员和安全管理提供有效依据。

关键词: 超高压天然气 ,  人口密集区域 ,  泄漏,  , 安全区域  三维数值模拟