Investigation of the Influence of Flow Pattern on the Internal Corrosion in Horizontal–Vertical Downward Pipe With Oil–Water Flow

Abstract In the petroleum and petrochemical industries, oil–water flow is widespread inside the pipes. The existence of water often results in internal corrosion in the horizontal–vertical downward pipe when water contacts the pipe wall. Surface wetting behavior and wall shear stress (WSS) are two important factors affecting corrosion procedure, which are governed by the flow patterns. With the propose to mitigate corrosion, focus shall be concentrated on the impact of flow pattern toward corrosion. In this work, the flow regime with oil–water flow in the horizontal–vertical pipe is investigated by computational fluid dynamics simulations. The cases with different mixture velocity (0.1 m/s–2.2 m/s) and different water cut (3%–40%) are investigated. The key discovery in this paper is that five types of flow patterns can be identified based on the multiphase flow in the horizontal–vertical pipe, which is rarely reported in recent work. According to the results of the surface wetting status and wall shear stress distribution, the severe corrosion area is predicted and classified into five types. The inside wall of elbows and the outside wall of vertical pipes are the area's most susceptible to corrosion, and the results are well in line with the on-site data.