Numerical Simulation of Gas-Liquid Slug Flow Along Vertical Pipes Using the Slug Tracking Model

The intermittent gas-liquid flow, or slug flow, in vertical tubes occurs over a wide range of gas and liquid flow rates, with many applications, such as oil industry. Predicting the properties of this kind of flow is important to design properly pumps, risers and other components involved. In the present work, vertical upward slug flow is studied through a one-dimensional and lagrangian frame referenced model called slug tracking. In this model, the mass and the momentum balance equations are applied in control volumes constituted by the gas bubble and the liquid slug, which are propagated along the pipe. The flow intermittency is reproduced through the conditions at the entrance of the pipe, which are analyzed in statistical terms. These entrance conditions are given by a sequence of flow properties for each unit cell. The objective of the present work is to simulate the slug flow and its intermittency through the slug tracking model. The numerical results are compared with experimental data obtained by 2PFG/FEM/UNICAMP for air-water flow and good agreement is observed.