油罐油气惰化置换过程数值模拟研究

基于对油罐惰气置换原理的分析,建立了油气惰化置换过程的紊流模型,采用压力和速度耦合场的PISO算法,完成了油罐惰气置换过程的数值模拟研究。用原型实验数据对模型进行了验证,经验证对比表明模型与实验结果吻合较好。进一步研究表明,对于3 000 m^3的油罐,约整个置换过程的前9 600 s,罐内气体处于爆炸燃烧范围,置换约9 600 s后油罐已处于安全状态;＂置换死角＂出现在靠近燃惰气进口两侧的中央偏下位置;罐内各气体组分除在靠近燃惰气进口一侧的较小空间内对流扩散速度较大外,其他大部分位置各气体组分对流扩散速度较小。这些结论将为油气惰化置换过程的进一步优化提供一定的参考依据。

Numerical Simulation Research of Oil-gas Inert Replacement Process in Oil Tank

Based on the principle analysis of oil-gas replacement in the oil tank,turbulence model of the oil-gas replacement process is founded,and PISO arithmetic of pressureand velocitycoupling fields is used to finish theinvestigationof oil-gas inert replacement in oil tank.It＇s found that the model tallies well with experiment results by testing and verifyingthe model with prototype experiment data.Further investigation shows that,for the tank with capacity of 3 000 m3,the gas in the oil tank may be in combusted and explodedat the beginning of the first 9 600 s in the replacementprocess,and then the oil tank will be in the safe condition;＂thereplacement dead space＂ will be appeared near the inert gas inlet below the middle of tank;the convection and diffusion velocityof the gasesin the tank is slow in most place of the tank,except the narrow space near the inert gas inlet.Those conclusionswill provide some references to the further optimization for the process in oil-gas inert replacement.