在内径150 mm的循环管路中开展了变流速工况下流动加速腐蚀试验,通过双环电阻传感器监测了X65管道内流动加速腐蚀的规律。同时,对每个流速状态下目标管段的流场进行了计算流体动力学(CFD)分析,并使用数码相机与扫描电子显微镜对双环电阻传感器测量环即管道周向的腐蚀形貌进行了观察。结果表明:由于弯管的影响,管道的外侧腐蚀比内侧严重,CFD结果也显示管道的外侧流速与壁面剪切力比内侧大;但是流动加速腐蚀并不完全由流场分布决定,形貌结果表明锈层的积累会对X65管道的腐蚀规律产生明显影响。

A flow accelerated corrosion test was carried out in a flow loop of pipeline with an inner diameter of 150 mm under the condition of variable flow rate, and the law of flow accelerated corrosion in X65 pipeline was monitored by ring pair electrical resistance sensor (RPERS). Computational fluid dynamics (CFD) analysis was performed on the flow field of the target pipeline segment in each flow rate state. The corrosion morphology of the measuring ring of the RPERS, that is, the circumferential direction of the pipeline, was observed using digital camera and scanning electron microscopy. The results indicate that the outer wall of the pipeline suffered more severe corrosion damage than the inner wall due to the influence of elbows. The CFD results show that the flow rates and wall shear stresses around the outer wall were higher than those of the inner wall. However, the flow accelerated corrosion did not completely depend on the distribution of flow field. The morphology results show that the accumulation of rust layer had an obvious effect on the corrosion law of X65 pipeline.