典型可燃气体小孔泄漏危险范围预测模型研究

Numerical simulation on prediction model of risk range of typical gas release through small holes

为了缓解我国石油资源紧张的现状,发展合成油工业作为我国石油资源的补充是合理的途径,而在化工合成中,大多数反应都需要在加压环境中进行。泄漏是最常见的事故之一,而现阶段对于加压装置、管道气体泄漏的研究还有待完善。因此,通过CFD(计算流体动力学)数值模拟的方法,以化工合成中常见的气体(H_(2)、CO、CH_(4))为研究对象,气体泄漏后危险浓度的范围作为气体泄漏危险范围,利用Fluent软件开展不同工况下气体泄漏扩散模拟,以研究不同气体、不同泄漏压力、不同泄漏温度以及不同泄漏口直径情况下气体泄漏扩散规律及泄漏危险范围,并构建泄漏危险范围预测模型。研究表明,在其他因素不变的条件下,随着泄漏压力的增大,气体泄漏危险范围随之增加;随着气体温度的增大,气体泄漏危险范围随之明显降低;随着泄漏口直径的增大,气体泄漏危险范围随之明显增加。在3个变量中,泄漏口尺寸的增大对于危险范围的扩大最为明显,当气体泄漏压力由1 MPa提高到2 MPa时,3种气体泄漏危险范围增加10%左右;当气体温度由300 K提高到400 K时,3种气体泄漏危险范围同样增加10%左右,而当泄漏口直径由2 mm增加到3 mm时,3种气体泄漏危险范围增加50%。通过对于3种气体(H_(2)、CO、CH_(4))数值模拟结果中的泄漏危险范围的长度、宽度数据的定量分析,并对于参量进行无量纲处理,最终分别得出3种气体(H_(2)、CO、CH_(4))泄漏危险范围(长度、宽度)的预测模型,其中泄漏危险范围长度和宽度为压力比和温度比的函数,预测结果可为泄漏事故救援和应急处理提供参考依据。

In order to relieve the shortage of petroleum resources,it is a reasonable way to develop synthetic oil industry as a supplement of petroleum resources.In chemical synthesis,most reactions need to be carried out in pressurized environment.Leakage is one of the most common accidents,and the research of gas leakage in pressurizing device and pipeline is still to be improved.Therefore,by CFD numeric al simulation method,this paper takes common gases(H_(2),CO,CH_(4))in chemical synthesis as the research object,and uses the range of dangerous concentration after gas leakage as the danger range of gas leakage.Fluent software is used to simulate gas leakage and diffusion under different working conditions.In order to study the gas leakage diffusion law and leakage danger range under different gas,different leakage pressure,different leakage temperature and different leakage port diameter,and build the prediction model of leakage danger range.The results show that the danger range of gas leakage increases with the increase of leakage pressure when other factors remain unchanged.With the increase of gas temperature,the danger range of gas leakage decreases obviously.With the increase of the diameter of the leakage port,the danger range of gas leakage increases obviously.Among the three variables,the increase of leakage port size has the most obvious effect on the expansion of the danger range.When the gas leakage pressure increases from 1 MPa to 2 MPa,the danger range of three kinds of gas leakage increases by about 10%.When the gas temperature increases from 300 K to 400 K,the danger range of three kinds of gas leakage also increases by about 10%,and when the diameter of the leakage port increases from 2 mm to 3 mm,the danger range of three kinds of gas leakage increases by 50%.By quantitative analysis of the length and width data of the leakage danger range in the numerical simulation results of three kinds of gases(H_(2),CO,CH_(4)),and dimensionless treatment of the parameters,the prediction models of the leakage danger range(length and width)of three kinds of gases(H_(2),CO,CH_(4))are finally obtained.The length and width of the leakage danger range are functions of pressure ratio and temperature ratio.The prediction results can provide reference for the rescue and emergency treatment of leakage accidents.