| dc.description.abstract | Two-phase oil-water flows in offshore pipelines are a common occurrence in the petroleum industry. As an oil reservoir mature, the presence of water in the retrieved oil increase. Understanding how this increased presence of water affects the hydrodynamic properties of the mixture is of great importance as it affects the operating conditions for the pipeline.
In this report, a review on the status of oil-water modelling is presented. The review covers the three main modelling approaches: empirical, analytical and numerical. The review highlights the different modelling techniques used in the studies and summarizes its findings. Additionally, an OpenFOAM CFD model based on the experimental work conducted by Kumara (2010) is made. The CFD model aims to predict the water volume fraction and mean axial velocity of a horizontal oil-water pipe flow at various operating conditions.
The findings from the review indicates that to increase the numerical accuracy for oil-water flows, the oil-water interface needs additional treatment. The presence of a turbulence damping scheme or boundary conditions are required to emulate the wall-like effect the oil-water interface represents. This wall-like effect was observed in the CFD simulations. The results showed that two-equation turbulence models like RNG k-ε, realizable k-ε and SST k-ω, were unable to accurately predict the complex nature of an oil-water flow. Of the three turbulence models, the SST k-ω model showed the best accuracy and should be used in any further research. The study concludes that the addition of a turbulence damping scheme, or similar interface treatment, is necessary to increase the numerical accuracy. | |
