The internal surface features of the long pipeline during its running process will change significantly by the influence of corrosion and fouling,and thus its flow field will change to result in the change of the fluid frictional resistance correspondingly.Currently,there are few studies in this fieldThe frictional resistance of inner pipeline after corrosion and fouling occur was analyzed through numerical simulation by FLUENT.The simulation results show that the circulation area of the pipe is decreased after fouling,and the drag coefficient along the pipeline becomes smaller,but the pressure drop per unit length and the total energy loss are increasedIn the case of corrosion,the drag coefficient along the pipeline and pressure drop per unit length are decreased,indicating that the pipe with irregular surface may have the position effect of drag reduction after adding corrosion pits.The research provides a reference for pipeline drag reduction based on surface texture design.