柱塞仿生表面织构设计和密封性能分析

Analysis of Plunger Bionic Surface Texture Design and Sealing Performance

排水采气柱塞的密封性能是柱塞气举排水采气工艺的关键。为研究不同柱塞表面织构对柱塞密封性能的影响,结合仿生学原理,选择矩形槽、圆弧槽、梯形槽、柱状坑和圆弧5种仿生表面织构,通过Computational Fluid Dynamics (CFD)流体模拟方法对柱塞举液上行过程中的气液两相流动进行模拟,对柱塞举液过程中的气液流动进行研究和分析,分析不同表面仿生织构对柱塞与油管壁间隙间流场流体流动和柱塞密封性能的影响。结果表明,柱塞上行过程中,仿生表面织构加剧了柱塞举液过程中气液两相流体相互作用,在织构区域形成局部湍流,消耗了气体的能量,阻碍了液体的漏失;相比于传统的槽状织构,凹坑状织构柱塞在合适的尺寸下的密封性能更好,模拟范围内密封性能最好的为圆弧坑织构,深6 mm,直径12 mm,周向均布8个。研究结果可为柱塞表面织构设计和柱塞举液工艺优化提供指导。

The sealing performance of the plunger in gas-lift drainage is crucial for the gas-lift drainage process.In order to investigate the influence of different surface textures on the sealing performance of the plunger,and in conjunction with biomimetic principles,five biomimetic surface textures,namely rectangular grooves,arc grooves,trapezoidal grooves,cylindrical pits,and arc pits,are selected.Computational Fluid Dynamics(CFD)fluid simulation is employed to model the two-phase gas-liquid flow during the plunger lifting process.The gas-liquid flow during the plunger lifting process is studied and analyzed,and the influence of different surface biomimetic textures on the fluid flow field between the plunger and the oil pipe wall gap and plunger sealing performance is analyzed.The results indicate that during the plunger lifting process,biomimetic surface textures intensify the interaction between gas and liquid phases,creating localized turbulence in the textured area,thereby dissipating gas energy and impeding liquid leakage.In comparison to traditional grooved textures,plunger surfaces with concave pit textures exhibit improved sealing performance,with the best performance observed for the arc pit texture with a depth of 6 mm,diameter of 12 mm,and eight evenly distributed around the circumference.These findings provide guidance for the design of plunger surface textures and the optimization of gas-lift drainage processes.