【作者】 王一；

【导师】 向阳； 多英全；

【作者基本信息】 北京化工大学 ， 化学工程（专业学位）， 2020， 硕士

【摘要】 社会发展对石油的需求量日益上升,油品储运设备的数量和规模也增长迅速,一旦发生油品泄漏不仅污染环境更容易引发火灾等事故,危害人员安全并造成经济损失。因此研究油品泄漏后的扩展规律及事故影响范围,对事故的预测分析、应急措施的制定具有一定指导意义。随着计算机运行能力和数值模拟领域的发展,CFD技术在分析流体流动和事故过程分析方面具有良好的优势。本论文基于CFD方法结合实验结果和理论分析,构建油品泄漏后在地面和水面形成液池的三维CFD模型,对液池面积和扩展运动等进行定性分析和定量描述。进而针对某一实际储罐区发生油品泄漏及池火灾事故,进行分析危害因素并确定安全距离,主要研究结果如下:(1)构建成品油在地面泄漏的CFD模型,研究溢油在地面形成液池的扩展过程以及液池面积的变化规律。模拟结果表明,液池在多种力作用下呈圆形向周围扩展,液池面积随时间线性增长。液池面积随泄漏速度、泄漏孔直径的增大而增大,随地面粗糙高度增大而减小,当粗糙高度小于0.005 m时,面积基本不再变化;而地面粗糙常数、所研究成品油的密度和黏度对液池面积影响较小。根据结果拟合地面上液池面积的计算关联式,模拟值与计算值误差范围约±15%。(2)构建水域静止点源溢油的CFD模型,研究水面油膜的扩展过程以及漂移运动。模拟结果表明,欧拉模型更适用于水面油膜的扩展过程,静水情况下油膜扩展初期处于重力-惯性力阶段且作用时间较短。油膜在风和水流作用下发生漂移运动,只有风作用时,油膜的运动过程与表层水的运动基本相同,风力因子与风速呈正相关,随风速增大呈增大趋势,我国大部分水域中油膜漂移速度为风速的5%以内;只有水流作用时,油膜漂移速度基本等于水速;当风和水流共存且同向时,油膜实际漂移速度要小于在风和水流单独作用下产生的速度代数和,减小约12%。溢油在地面和水面上扩展时,在作用力阶段主要是惯性力和表面张力的不同。(3)构建某实际储罐区发生油品泄漏及池火灾的事故情景,事故中产生较为严重的爆炸冲击波,影响范围约35 m;开放环境中燃烧产生的烟尘等有毒有害物质含量少且影响范围较小。热辐射作为最大危害因素,距离事故储罐越远热辐射的危害越低;罐组内其他储罐都将接受过高热辐射可能导致罐壁破裂发生连续事故。热辐射影响范围的模拟值与经验计算值增长趋势相似,模拟值偏大约10%,热辐射的安全防护距离约160 m。更多还原

【Abstract】 As the driving force of social development,the number oil storage and transportation facilities grow rapidly.When oil leaks,not only environment get polluted,but is more likely to endanger human safety and cause economic losses.Hence study the oil spill process and the influence scope of accident is significant,which provides theoretical reference for the prediction and analysis of oil leakage accident and emergency measures.With the development of computer operation capability and numerical simulation,CFD is good at analyzing the fluid flow and accident process.Based on previous experimental results and theoretical analysis,CFD is used to study the formation process of liquid pools on the ground and water after oil leakage,with the qualitative and quantitative analysis.The hazard factors and safety distance are determined of oil leakage and pool fire in an actual tank area,the conclusions are as follows:(1)The CFD model of oil leakage on the ground is built,the expansion process of liquid pool and the change law of pool area are studied.Results show that pool expands in a circular direction and area increases linearly with time.The pool area increases with leakage velocity and leaking hole diameter,decreases with roughness height,while stay unchanged when roughness height is less than 0.005 m.However,roughness constant,oil density and viscosity show little effect on pool area.The calculation correlation formula of pool area is fitted,the error between simulated and fitting value is about±15%.(2)The CFD model of oil spill from a static point in the water is bulit,the expansion and movement process of oil film are studied.Results show that Euler model is more suitable for expansion process on water,the initial stage of expansion can be completely described by gravity-inertia force,but the acting time is short.The wind factor is positively correlated with wind velocity,which tends to increase with it,the drift velocity of oil film in most waters is about 5%of wind velocity,which is basically equal to water velocity.When wind and water flow coexist and move in the same direction,the drift velocity of oil film is less than the sum velocity generated under the action of wind and water flow alone,which decreases by about 12%.The main difference are inertial force and surface tension in force phase when oil spill spreads on the ground and water.(3)An accident scenario of oil leakage and pool fire in a tank area is constructed,results show that the influence range of explosion shock is about 35 m.In the open environment,the content of toxic and harmful substances such as dust is few and the influence range is small.Thermal radiation is most harmful,the farther away from the accident tank the lower harm of thermal radiation is.Other nearby storage tanks will receive excessive thermal radiation,which may lead to ruptures of tank wall.The simulated value of influence range of thermal radiation is about 10%larger than the empirical one,while both of the growth trend is the same.The safety protection distance of thermal radiation is about 160 m.更多还原