Numerical Simulations Of Two-phase Flow On Crude Oil With Low Water Content In Inclined Pipelines

With the the demand for crude oil's import is increasing in China, pipelines have been the main form of long-distance transmission of crude oil. However, the problem of perforation caused by corrosion occurs frequently. Therefore, corrosion is one of the key factors which influence reliability and service life of pipeline system and is also a central issue of research of pipeline system. Imported crude oil has low water content. Its flow field of oil-water two-phase flow is very different from that of crude oil with high water content. Therefore, the flow field of crude oil with low water content in inclined pipelines through the combination of the actual working condition of pipelines of Zhenjiang Refining and Chemical Company was simulated in this paper.The research of oil-water two-phase flow is mainly divided into two parts: experiment and stimulation. The data of experiments cannot provide enough contrasts. In recent years, the simulation and analysis of flow field in pipelines through computer numerical simulation technology based on CFD can reveal corrosion mechanism in oil-water pipelines in essence and provide scientific basis for finding the most dangerous place of whole pipeline system.Through CFD software, three-dimensional pipeline modes with inclinated angles of 0°,5°,10°,15°,20°,25°and 30°, and water contents of 0.1%,0.5%,1.5%, 5% and 10% respectively were constructed, then unstable calculations with VOF mode of multi-phase flow were done, finally flow field of oil-water two-phase flow and collection of water in the pipeline was analyzed, and the pressure, velocity, distribution of water phase of pipeline was analyzed by different angles and water contents.The calculation findings and the analysis of flow field show that with the influence of inclined angle and gravity, crude oil with low water content can be easily collected at rising part, middle part and outlet of the inclined pipelines. The pressure falls along the pipelines, but the fall degree becomes small. With an increase of inclined angle, the pressure at the linking part increases, the turbulence and the partial countercurrent appears. With the increasing water content, the influence of the change of water content towards the change of pressure in the pipelines can be ignored, fluctuation of speed is big, and fault at the linking part appears.At last, analysis and comparison of the multi-phase flow simulation which is done through OLGA software and findings by FLUENT simulation was made. The findings of simulation show that the findings of two modes about oil-water two-phase flow of crude oil with low water content are identical. The findings of simulation and the findings of field inspection are identical. The results in the paper are positive in predicting pressure drop, reducing energy consumption and making significant anticorrosion measures.