Numerical Investigation of the Behavior of an Oil-Water Mixture in a Venturi Tube

This work is devoted to numerical investigations of cavitating oil-water flows inside a Venturi tube. The Eulerian-Eulerian multiphase model available in the commercial CFD software ANSYS FLUENT 16.2 is used to explore the cavitation behavior of an oil-water mixture containing 10% water. Four different cases are considered for different oil viscosities (mu(o) = 0.029, 0.29, 1, and 2.9 kg/(m s)). The results of the simulations revealed that the increase in oil viscosity restricts the development of cavitation at the Reynolds numbers of the oil phase, Re-in,Re-o, between 15 and 1618. However, it was found that at the highest viscosity of oil considered in this work, the cavitation phenomenon starts at Re-in,Re-o = 15 and increases more rapidly in terms of the flow rate in comparison with two cases with low oil viscosity. In addition, we found out that in the case with the highest oil viscosity, the cavitation starts in the laminar flow, while at lower oil viscosities, the cavitation is characterized by the turbulent flow regime.