Correlation between corrosion behavior and fluid dynamic parameters of contraction segment of pipeline

Flow accelerated corrosion test was conducted in a loop system for contraction segment of N80 pipeline using array electrode technique. Through electrochemical test, surface morphology analysis and fluid dynamic simulation, the corrosion behavior at different locations of contraction segment was studied, and the correlation between corrosion behavior and fluid dynamic parameters was also clarified. The results show that the corrosion rates of different locations on the contraction segment varied greatly. There was a clear flow acceleration corrosion phenomenon in the contraction segment, and the corrosion rate of the contraction segment was obviously different from that of common segment. The corrosion rate distribution was in good accordance with the distribution of fluid dynamic parameters on the contraction segment, that is, the lower the corrosion rate, the lower the velocity and the smaller the wall shear stress, and vice versa.