Abstract This paper focuses on the dispersion behavior of gas released from underwater soil by using experimental and numerical approaches. A small-scale experimental system is developed and a number of release scenarios are carried out. The results indicate that the released gas breaks through the sand layer after consuming a certain amount of initial energy and enters the water in the form of bubble plumes, which is similar to the theoretical model. The plume interacts intensely with the surface and forms a fountain with a periodic change in height. The effect of leak pressure, water depth and buried depth on plume behavior and critical parameters including plume diameter, fountain height and rise time are discussed. The experimental data are also utilized to verify the effectiveness of the presented numerical model using Eulerian-Eulerian volume of fluid (VOF) approach. The validated numerical model is subsequently employed to analyze three full-scale scenarios, and the results show good consistency with the experiments. Both the experiments and numerical models are of great value for evaluating the consequences of gas released from underwater buried pipelines and providing data and theoretical support for the subsequent risk assessment.

中文翻译：

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水下土壤气体释放与扩散的实验与数值研究

摘要 本文通过实验和数值方法研究了水下土壤释放气体的弥散行为。开发了一个小规模的实验系统，并进行了多个发布场景。结果表明，释放的气体在消耗一定的初始能量后突破砂层，以气泡羽流的形式进入水中，与理论模型相似。羽流与地表强烈相互作用，形成高度周期性变化的喷泉。讨论了泄漏压力、水深和埋藏深度对羽流行为和包括羽流直径、喷泉高度和上升时间在内的关键参数的影响。实验数据还用于验证使用欧拉-欧拉流体体积 (VOF) 方法提出的数值模型的有效性。随后采用经过验证的数值模型对三种全尺寸场景进行分析，结果与实验具有良好的一致性。实验和数值模型对于评价水下埋地管道释放气体的后果以及为后续风险评估提供数据和理论支持具有重要价值。