由于一些已经使用了150多年的管道的长期使用,埋地管道的泄漏事故变得越来越普遍。因此,迫切需要准确预测污染范围,以帮助制定紧急修复策略。本研究通过数值模拟和实验室实验研究了轻质非水相液体在含有气体和水的土壤中的分布。首先,利用ANSYSFLUENT建立了三维多孔介质模型,第一次,在模型中模拟了土壤环境中气体和地下水的分布。随后,柴油的三个阶段的分布,气体,研究了不同渗漏速度下的土壤水分,发现渗漏速度在分布中起着重要作用。60分钟时土壤中柴油的面积为0.112m2,0.194m2,0.217m2和0.252m2,相应的体积分别为0.028m3,0.070m3,0.086m3和0.106m3,对于1.3m/s的泄漏速度,3.4m/s,4.6m/s,和4.9米/秒。还开发了分布面积和体积的计算公式,以帮助未来在不同泄漏速度下的预防和控制策略。该研究还比较了有和没有地下水的土壤中柴油的分布面积和体积,发现由于毛细作用力,在含地下水的土壤中分布范围更大。为了验证数值模拟的准确性,进行了实验室实验来研究油的扩散,气体,和不同泄漏速度下的水。结果表明,实验和模拟之间具有良好的一致性。研究结果对防治土壤污染具有重要意义,为制定科学合理的土壤修复策略提供理论依据。
Leakage accidents of buried pipelines have become increasingly common due to the prolonged service of some pipelines which have been in use for more than 150 years. Therefore, there is an urgent need for accurate prediction of pollution scope to aid in the development of emergency remediation strategies. This study investigated the distribution of a light non-aqueous phase liquid in soils containing gas and water through numerical simulations and laboratory experiments. Firstly, a three-dimensional porous medium model was established using ANSYS FLUENT, and for the first time, the distribution of gas and groundwater in soil environments was simulated in the model. Subsequently, the distribution of the three phases of diesel, gas, and water in soil was studied with different leakage velocities and it was found that the leakage velocity played a significant role in the distribution. The areas of diesel in soils at 60 min were 0.112 m2, 0.194 m2, 0.217 m2, and 0.252 m2, with corresponding volumes of 0.028 m3, 0.070 m3, 0.086 m3, and 0.106 m3, respectively, for leakage velocities of 1.3 m/s, 3.4 m/s, 4.6 m/s, and 4.9 m/s. Calculation formulas for distribution areas and volumes were also developed to aid in future prevention and control strategies under different leakage velocities. The study also compared the distribution areas and volumes of diesel in soils with and without groundwater, and it was found that distribution scopes were larger in soils containing groundwater due to capillary force. In order to validate the accuracy of the numerical simulation, laboratory experiments were conducted to study the diffusion of oil, gas, and water under different leakage velocities. The results showed good agreement between the experiments and the simulations. The research findings are of great significance for preventing soil pollution and provide a theoretical basis for developing scientifically sound soil remediation strategies.