This study introduces the application for the mixture model to simulate the liquid–liquid flow through complex pipeline configurations. The model is validated by comparing model predictions with published experimental data and showed reasonable agreement. The model is used to calculate the naphtha–water flow through a complex pipeline configuration with straight pipes and elbow fittings. The selected pipeline suffers from corrosion problems. The effect of different fittings on the pipeline is taken into account. The results obtained here showed that the mixture model is appropriate two-phase flow model and could be used to explain the reasons why specific locations in the pipeline suffer from corrosion problems while other locations do not suffer from these problems. These locations are predicted with good agreement with field measurements of corrosion distribution. It was concluded through this study that the mixture model can predict the two-phase flow features with reasonable accuracy and during relatively short computational time.