Abstract: People around the world have paid more and more attention to the problem of oil volatilization, because of the enforcement of laws on energy saving and lots of accidents caused by oil diffusion. It is important for people to find the laws of oil volatilization. That could reduce the oil diffusion during its transportation and storage, decrease the pollution, and prevent the occurrence of related accidents. Data of oil and gas diffusion in tank is obtained using the model of VOF that comes from CFD by considering the influence of wind speed, wind direction and tank type. It is also a good choice to use UDF as the source of the simulation analysis. The results show that wind speed has a great effect on oil evaporation. And the wind direction that perpendicular to the wall of the tank has evident effects. According to the study on evaporation loss of oil, the petrochemical plants must take some effective measures to reduce the oil diffusion, and reduce the risk of explosion. 

Key words: Safety engineering, Oil vapor diffusion, Numerical simulation, Storage tank, Phase change

摘要： 研究油品蒸发损耗的规律，对于有效地减少油品在储存和运输过程中的挥发，保障油品的质量、降低环境污染以及有效地预防因油气扩散而引发的爆炸事故具有重要的意义。利用CFD中VOF模型，采用UDF作为源项进行模拟分析，总结出不同风速、风向以及罐型条件下，罐内油气扩散情况。研究表明，风速对油品挥发有很大的影响，尤其以垂直于罐壁处的风向影响最为显著。根据模拟，总结出油品在不同条件下的蒸发损耗的规律，选择适合石化企业节能减排、规避风险的措施，可以有效地减少事故的发生，降低环境污染。

关键词: 安全工程, 油气扩散, 数值模拟, 储罐, 相变