Numerical modelling of carbon dioxide leakage from an offshore pipeline

Abstract

A three-dimensional transient computational model was developed to simulate the break up of carbon dioxide escaping from a pipeline leak to the seawater. Important physical phenomena such as turbulence and mass transfer during evaporation of the initially liquid CO2 stream are included in the model. Sensitivity of the model for mesh size, turbulence model and the order of the spatial discretisation scheme are shown for different scenarios. A three stage approach is used to achieve sufficient level of convergence for the transient multiphase turbulent flow simulation using the Span and Wagner equation of state and a high-order discretisation schemes. The scenarios considered in this study include a wide range of pipeline operating pressure, ambient seawater depth and leakage size.