Outdoor Pipeline Gas Leakage Diffusion And Visualization Simulation Research

In the development and utilization of natural gas, city gas pipeline-network is more and more complicated. City gas pipelines always distributed in concentrated areas with population and buildings, making the natural gas became to the most frequent accident, the most serious consequences one of the toxic flammable gas. To master the law of natural gas leakage and diffusion can be useful to accurately predicted, evaluation and control it, reducing gas pipe-conveying accidents.In this paper, a model of natural gas continuous leakage and diffusion of outdoor pipeline is established. Theoretical analysis, numerical simulation, and3D display are used.1. Gas thermodynamics, kinetics, turbulent diffusion gradient theory and statistical theory are applied to do the based analysis before modeling. On the basis of the Gaussian point source diffusion model, considering the uplift height of natural gas, using mobile puff integral model to establish a natural gas continuous leakage and diffusion model of ground point source, under the small and static wind conditions, with and without ground reflection.2. Using Matlab to do a mathematicl calculation about the model, using Fluent to make numerical simulation with the leakage and diffusion of natural gas under the same conditions. The results show that this model is consistent with fluid mathematical partial differential equations.3. The introduction of GIS analysis software is useful to display the model dynamically. By using the ArcGIS9.3as a base platform, to target with campus to visualization, using graphic GIS data collected to build the three-dimensional visualization scene. Make the leak source as the center of three-dimensional spatial discrete grid, using Matlab to calculate the concentration distribution. Finally,3DS Max’s particle system is supported to the spread of three-dimensional dynamic visualization.In this paper, Gaussian model of atmospheric study is applied to gas. Based on the special meteorological conditions in Chongqing, a model of continuous leakage diffusion of natural gas of point source under the small and static wind is established. And it was displayed dynamically in3D scene. The model has a very good compatibility with atmospheric diffusion theory, besides, it also accorded with numerical simulation and practical, can be applied in practice conveniently.