Simulation of oil-water two phase flow and separation behaviors in combined T junctions

The combined T junctions used for the oil-water separation have the advantages of compactness in structure, consistency in effects and economy in cost. The mixture k – ɛ turbulence model and the Eulerian multi-fluid model are used to simulate the flow and phase distribution in the combined T junctions. The effects of structural parameters such as the branched pipe interval and height on the flow distribution and the separation behaviors are studied. The results show that the combined T junctions under fixed inlet and outlet boundary conditions form a single hydraulic equilibrium system in which the fluid energy distributes freely till a balance is achieved. The split-flow promotes the separation of the immiscible oil and the water. The separation efficiency increases with the increase of the branched pipe interval and changes slightly with the increase of the branched pipe height. The structural change of the combined T junctions may change the flow direction in the branched pipes. Simulation results can provide some guidance for the design of the combined T junctions as one kind of oil-water separator.