Pressure drop and holdup models in oil-water core-annular flow: A review
Authors :- Gautam S.; Saini M.; Tripathi S.
Publication :- AIP Conf. Proc. 2960, 030016 (2024)
Large amounts of heavy oil are readily available all over the world, but their high viscosity makes the extraction and transportation very challenging. Typically, the flow of a high viscosity fluid (such as heavy oil) in a pipeline while being lubricated by a low viscosity fluid (such as water) is called Core-Annular Flow (CAF). In CAF, the more viscous liquid takes up the region close to the pipe center, and the less viscous liquid flows alongside the pipe wall where significant wall shear stresses are present. The CAF arrangement is governed by several parameters including fluid properties, flow characteristics, and piping arrangements. The stability of CAF is primarily governed by viscous forces, inertial forces, and buoyancy forces, and also influenced by the relative flow rates of the two liquids as well as the geometric configuration of the piping system. The key parameters of interest in a CAF arrangement are pressure drop and hold-up. In the present work, we review various correlations available in the literature on predicting pressure drop as well as hold-up in a water lubricated transportation of heavy oil in a CAF arrangement.