关键词:  天然气管道, 泄漏, 扩散, UD F, 数值模拟

Abstract: According to different damage process of natural gas pipeline leakage diffusion problems, using FLUENT software, CFD simulation model was established, and studied the different leak diameter of the effects on gas leakage diffusion area and simulated the natural gas leak and diffusion process between mountain and city terrain. The situation of wind speed changing along with the height and mass discharge rates variable with the time were taken into account and UDFs were programmed into the FLUENT to amend them. It concluded that the bigger hold can achieve the higher range, the max lower explosive limit of the high from the ground and downwind horizontal distances of diameter of 6.35 , 25.40 mm and 101.60 mm were 92 m and 322 m,122 m and 770 m, 408 m and 1291 m. When diffuses on the surface and in the soil, the 101.60 mm leak diameter had the maximum diffusion range. The biggest downwind horizontal distances were up to 80 m and 105 m respectively. This was because the gas lost a lot of turbulent energy influenced by the soil above the pipeline.

Key words: Natural gas pipeline, Diffusion, Leak, UDF, Numerical simulation