携砂管流临界输运特性研究进展

在含砂油气集输管道中,如果流速控制得过小,砂粒则会在管道底部发生沉积,导致管道流通面积减小甚至完全堵塞、砂层下腐蚀穿孔、清管频繁或"卡球"等诸多问题;而流速太大,则可能造成管道弯头等管件的冲刷破坏,因此研究携砂管流的临界输运特性至关重要。分析了携砂管流面临的沉积、冲刷等流动安全问题,较为详细地阐述了固体颗粒在液体管道与在多相流管道中输运的实验和理论研究进展。指出了悬浮液中颗粒浓度远高于油气集输管道通常遇到的浓度,其关联式不适用于油气集输管道,不同流型下砂粒的沉积-冲蚀一体化模型将是油气集输管道下一步急待研究的课题。

Research Advances in Critical Transport Characteristics of Pipe Flow with Sand

In the flowing process of the oil and gas gathering pipelines carrying a certain amount of sand,the sand will deposit at the bottom of the pipe when the flow rate is too small.This will lead to a series of problems,such as the decrease of the flow area ,the complete blockage,the corrosion perforation under the sand layer,and the frequent pigging or the "stuck ball".On the other hand,when the flow velocity is too high,the erosion of the pipe elbows can be caused. Therefore,the critical transport characteristics of the pipe flow with sand are very important. The deposition and erosion problems of the pipe flow with sand are analyzed, and the experimental and theoretical research advances of solid particles transporting in liquid pipelines and multiphase flow pipelines are described in details.The results show that the correlation of the suspension is hardly fit for the oil and gas gathering pipelines due to the big difference of the particle concentration, and the unified sand deposition-erosion model under different flow patterns will be an urgent task for the next step for the oil and gas gathering pipelines.