Pressure gradient prediction of oil-water two phase flow through horizontal pipe

In this thesis, stratified and stratified wavy flow regimes have been investigated numerically for the oil (1.57 m Pa s viscosity and 780 kg/m3 density) and water two-phase flow in small and large horizontal steel pipes with a diameter between 0.0254 to 0.508 m by ANSYS Fluent software. Volume of fluid (VOF) with two phases flows using two equations family models (Realizable k- ε and Shear Stress Transport k–ω (SST)) in turbulence modeling is applied used to simulate flow to obtain the hydrodynamic parameters effect of velocities in the range of 0.2-1.2 m/s, volume fraction of water in the range of 20-80 %; and diameters on the pressure gradient. The results show that the pipe diameter has a large effect on the pressure gradient. Furthermore, it was found that at 40 % and 60 % water volume fraction for large diameters, where stratified wavy flow patterns prevail, there is a peak in the pressure gradient during phase inversion. The pressure gradient is found by Shear Stress Transport k–ω turbulence model better than those found by Realizable k- ε turbulence model according to compare with published experimental studies. Keywords: CFD, two-phase flow, pressure gradient, volume of fluid, large diameter, horizontal pipe, oil-water stratified and stratified wavy flow.