利用CFD软件Fluent建立二维全尺寸仿真模型,对立管实验装置中的严重段塞流现象进行数值模拟研究。模拟方法中,采用液体体积函数(volume of fluid,VOF)法追踪气液界面;将长距离海底管道等效为箱体,以提高计算效率。模拟出了立管系统中的...利用CFD软件Fluent建立二维全尺寸仿真模型,对立管实验装置中的严重段塞流现象进行数值模拟研究。模拟方法中,采用液体体积函数(volume of fluid,VOF)法追踪气液界面;将长距离海底管道等效为箱体,以提高计算效率。模拟出了立管系统中的四种流型:典型严重段塞流(SSI)、严重段塞流II(SSII)、过渡流型(SST)和稳定流动;并对这四种流型的模拟结果进行了实验验证。最后,对典型严重段塞流的瞬态流动特性进行了深入分析。结果表明:采用数值模拟方法计算效率高,可准确模拟严重段塞流现象,为长距离立管系统中严重段塞流研究提供了切实可行的模拟方法。模拟工况下,气液喷发的瞬时质量流量可达入口的2.5倍以上,气液平均流速可达入口的4.5倍以上,其瞬态流动特性的分析对严重段塞流危害的准确评估有重要意义。展开更多
During the exploitation of offshore oil,it is easy to form severe slugging in the riser system at a low gas-liquid velocity.The magnitude of the pressure fluctuation can be significantly high,causing dramatic change o...During the exploitation of offshore oil,it is easy to form severe slugging in the riser system at a low gas-liquid velocity.The magnitude of the pressure fluctuation can be significantly high,causing dramatic change of flow rate and leading to other damages.In this paper,the characteristics of slug velocity during the four stages of severe slugging in the pipeline-riser system were studied.It was found that the slug head rose in the riser at a constant velocity in the slug formation stage.At the same time,the direction of slug tail movement was opposite to the flow direction,and the tail velocity kept constant when flowing through the inclined pipe.In the process of blowout,the liquid velocity in the pipeline-riser system increased and reached a maximum value when the slug tail reached the top of the pipeline-riser.At this moment,the instantaneous flow rate was much larger than that in the slug production stage.展开更多
文摘利用CFD软件Fluent建立二维全尺寸仿真模型,对立管实验装置中的严重段塞流现象进行数值模拟研究。模拟方法中,采用液体体积函数(volume of fluid,VOF)法追踪气液界面;将长距离海底管道等效为箱体,以提高计算效率。模拟出了立管系统中的四种流型:典型严重段塞流(SSI)、严重段塞流II(SSII)、过渡流型(SST)和稳定流动;并对这四种流型的模拟结果进行了实验验证。最后,对典型严重段塞流的瞬态流动特性进行了深入分析。结果表明:采用数值模拟方法计算效率高,可准确模拟严重段塞流现象,为长距离立管系统中严重段塞流研究提供了切实可行的模拟方法。模拟工况下,气液喷发的瞬时质量流量可达入口的2.5倍以上,气液平均流速可达入口的4.5倍以上,其瞬态流动特性的分析对严重段塞流危害的准确评估有重要意义。
文摘During the exploitation of offshore oil,it is easy to form severe slugging in the riser system at a low gas-liquid velocity.The magnitude of the pressure fluctuation can be significantly high,causing dramatic change of flow rate and leading to other damages.In this paper,the characteristics of slug velocity during the four stages of severe slugging in the pipeline-riser system were studied.It was found that the slug head rose in the riser at a constant velocity in the slug formation stage.At the same time,the direction of slug tail movement was opposite to the flow direction,and the tail velocity kept constant when flowing through the inclined pipe.In the process of blowout,the liquid velocity in the pipeline-riser system increased and reached a maximum value when the slug tail reached the top of the pipeline-riser.At this moment,the instantaneous flow rate was much larger than that in the slug production stage.
