Abstract To provide a more reliable theoretical basis for emergency-management decisions following accidental natural gas leaks, a numerical simulation and an experiment were conducted in this study to investigate the effects of complex construction environments on natural gas leakage and diffusion laws. The design of a building was divided into an enclosed layout, a patch layout, and a street canyon layout, from the perspective of their impact on environmental winds. Natural gas leakage and diffusion in three layouts were simulated using a three-dimensional computational fluid dynamics (CFD) model, in which both the distribution of natural gas concentration and dangerous areas were determined through comparative analysis. The results of a small-sized experiment showed that the blocking function of an enclosed layout for environmental wind was the highest, its vortex effect was the strongest, and its range of high gas concentration was the widest among the layouts. A cavity among the buildings was the site of major gas accumulation, making it the most crucial area for the emergency management of accidental natural gas leaks. The proposed CFD model was demonstrated be able to be used to simulate and predict the diffusion of natural gas in cases of accidental leakage. And the results of this study can guide building layout planning and gas pipeline construction to prevent accidents.

中文翻译：

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不同建筑布局下城市天然气泄漏扩散规律的数值模拟与试验

摘要 为为天然气意外泄漏事故应急管理决策提供更可靠的理论依据，通过数值模拟和实验研究复杂施工环境对天然气泄漏扩散规律的影响。建筑设计从对环境风影响的角度，分为封闭式布局、补丁式布局和街道峡谷式布局。采用三维计算流体动力学（CFD）模型模拟​​三种布局的天然气泄漏和扩散，通过对比分析确定天然气浓度分布和危险区域。小型试验结果表明，封闭式布局对环境风的阻隔作用最高，涡流效应最强，高气体浓度范围在所有布局中最广。建筑物之间的空腔是主要气体聚集的场所，使其成为事故天然气泄漏应急管理的最关键区域。所提出的 CFD 模型被证明能够用于模拟和预测意外泄漏情况下的天然气扩散。研究结果可指导建筑布局规划和输气管道建设，预防事故发生。使其成为天然气意外泄漏应急管理的最关键领域。所提出的 CFD 模型被证明能够用于模拟和预测意外泄漏情况下的天然气扩散。研究结果可指导建筑布局规划和输气管道建设，预防事故发生。使其成为天然气意外泄漏应急管理的最关键领域。所提出的 CFD 模型被证明能够用于模拟和预测意外泄漏情况下的天然气扩散。研究结果可指导建筑布局规划和输气管道建设，预防事故发生。