Progress Update: Slug Flow Evolution in Gas-Oil-Water Flow in Hilly-Terrain Pipelines
February 26, 2010
A hilly-terrain pipeline consists of horizontal, upward inclined, and downward inclined sections. Hilly terrain pipelines are common in both onshore and offshore production and transportation systems. Understanding the characteristics of slug flow in hilly-terrain pipelines help prevent or reduce the operational problems, flooding of downstream facilities, severe pipe corrosion, and structural instability, as well as production loss. The general objectives of this project are to investigate and develop models for the slug flow characteristics in three-phase gas-oil-water flow in hilly-terrain pipelines based on an extensive analysis of the distribution of the phases, slug dissipation, generation and growth with changing water cuts.
The gas-oil-water facility of TUFFP was modified for the experimental part of this study. A total of 110 tests were conducted for water cuts of 20%, 40%, 60% and 80% with an inclination angle 5° for the valley configuration. Data analysis is conducted by analyzing three-phase flow patterns before and after the hilly-terrain unit, pressure drop and change in slug characteristics with water cuts from the outputs of pressure transducers, laser and capacitance sensors and videos. The three-phase slug characteristics data are compared with Zhang et al.’s (2003) slug dissipation model and transient multiphase simulation, OLGA™. Further data analysis and modeling studies for developing three-phase slug flow are still underway and will be completed by May 2010.