CFD studies on the high-viscosity oil-water two-phase flow in a horizontal pipe

Abstract

In order to enhance the understanding of co-current oil-water flow behavior in a horizontal pipe, CFD studies of the oil-water transient model flow were carried out. In the present work, the flow simulation was solved numerically using Volume-of-Fluid (VoF) multiphase model while the turbulence model was performed using the SST k-ω. In addition, the viscosity of oil was sensitive to the temperature changes that influenced the changes in flow patterns. Therefore, the energy equation solver was also activated to observe the flow changes due to this case. The oil and water superficial velocity ranges were between 0.06-0.4 m/s and 0.18-0.81 m/s. The water flow temperatures were varied by 300K and 373K. The oil-water density was adjusted to have approximately matched values while a medium API for the oil characteristic model was selected. The computational domain was observed on a pipe with 26mm in diameter and 1m in length for the primary pipe, while the oil and water inlets diameter were set to 12mm. A comparison with experimental data showed relatively good agreement, both qualitative and quantitative. Furthermore, the flow characteristics were obtained with satisfactory predictions in particular different flow regimes. Here, the quantitative results of oil volume fraction were investigated as well. This study also found that increasing temperature affected flow behavior and transformed the oil lumps in water flow pattern into the stratified flow. Moreover, the numerical simulation appeared to be a reliable tool for predicting oil-water flow characteristics and investigating the influence of temperature in the flow.