汽油长输管道泄漏扩散的数值模拟

Simulation of Long-distance Gasoline Pipeline's Leak and Diffusion

成品油属易燃危险品,其长输管道一旦发生泄漏事故,就会造成管道停输、油品损失、环境污染甚至发生燃烧爆炸等严重后果,造成巨大的经济损失。因此研究汽油管道在不同条件影响下的泄漏扩散规律,将为事故预防和优化设计提供理论参考。本文基于流体动力学方法,建立管道泄漏的网格空间,采用VOF的非稳态多相流可实现的κ-ε模型来模拟汽油从高压管道内射流到空气中的过程。计算结果表明,在相同泄漏孔径下,汽油的喷射浓度随风速的增强在高度方向上变小,其偏转度随风速的增强而变大。在相同风速下,泄漏孔径的增大使汽油的喷射高度增加,随着高度的增加,汽油也从紊流区向层流区过渡,在其过渡层内,流体的层流运动和漩涡运动同时存在,又使在一定高度方向上风速对汽油喷射的影响加强。

Gasoline is a kind of dangerous and combustible good.It will lead to the shutdown of the pipeline,the loss of gasoline and the pollution of the environment when the long-distance gasoline pipeline began to leak,and even turn out explosion.They would cause significant economic losses.Therefore,simulating the progress of the leak and diffusion of gasoline under different conditions will make a reference for the prevention of accident and optimal design.Computational fluid dynamics method was used in the study,grid space of leak of pipelines was established,and realizable κ-ε model was chosen on the basis of unstable volume of fluid.It indicated the process of the gasoline which from the high press pipeline jet into the air.The results indicate that the spray concentration varies smaller in the height direction and the deflection becomes larger with the enhancement of the wind force.In the condition of constant velocity of wind,the increases of the leakage aperture promote gasoline injection in the height direction.And with the increase of height,gasoline from the turbulent zone translates to the laminar zone.In the transition,the laminar flow motion and vortex motion that exist at the same time strengthen the impact of wind force on the gasoline injection.