液固两相流对高压活动弯头的冲蚀磨损研究

Research on Erosion and Wear of High-Pressure Movable Elbows Caused by Liquid-Solid Two-Phase Flow

为探究水力压裂作业中各因素对活动弯头的冲蚀磨损规律,基于液固两相流理论,利用FLUENT软件研究压裂液流速、颗粒质量流量、颗粒直径、安装角度、公称直径、连接长度、曲率半径对活动弯头冲蚀速率的影响。结果表明:活动弯头易冲蚀区域主要集中在弯头外侧,其最大冲蚀速率和平均冲蚀速率随流速、颗粒质量流量、颗粒直径的增大而增大,随安装角度、公称直径的增大整体上逐渐减小,安装角度位于90°~180°时,最大冲蚀速率和平均冲蚀速率较小且变化平缓;随曲率半径的增大,最大冲蚀速率整体上先减小后增大,平均冲蚀速率逐渐减小;连接长度对最大冲蚀速率和平均冲蚀速率的影响较小。研究表明,压裂液流速是导致冲蚀速率增加的主要因素,通过合理调整压裂液流速可以大大降低活动弯头的冲蚀磨损。该研究结果可为活动弯头的现场使用、冲蚀防护、结构改进及优化提供参考。

To explore the erosion and wear laws of various factors on the movable elbow in hydraulic fracturing operations,based on the theory of liquid-solid two-phase flow,the influence of fracturing fluid flow rate,mass concentration,particle diameter,installation angle,nominal diameter,connection length,and curvature radius on the erosion rate of the movable elbow was studied using Fluent software.The results show that the erosion prone areas of the movable elbow are mainly concentrated on the outer side of the elbow.The maximum erosion rate and average erosion rate of the movable elbow increase with the increase of flow velocity,particle mass flow rate,and particle diameter,but gradually decrease overall with the increase of the installation angle and nominal diameter.When the installation angle is between 90°and 180°,the maximum erosion rate is relatively small and the change is relatively gentle.As the curvature radius increases,the maximum erosion rate generally decreases first and then increases,while the average erosion rate gradually decreases.The influence of connection length on the maximum erosion rate and average erosion rate is relatively small.Research shows that the flow rate of fracturing fluid is the main factor leading to an increase in erosion rate,and the erosion and wear of movable elbows can be greatly reduced by adjusting the flow rate of fracturing fluid reasonably.The research results can provide reference for the on-site use,erosion protection,structural improvement,and optimization of movable elbows.