Numerical analysis of dispersion characteristics of underwater gas-oil two-phase leakage process.

Fatigue failure, third-party destruction and internal corrosion may easily trigger gas and oil leakage during the operation of submarine multiphase pipelines. In order to analyze the underwater gas-oil plume development and migration law, a 3D model based on coupled Eulerian-Lagrangian numerical approach is proposed. The model is validated by laboratory experiment and the dynamic dispersion process of gas-oil plume in a large scale shallow sea environmental is further explored. Influencing factors such as leak location, leak size and water depth, flow pattern are investigated. The simulated results show that leak location affects the gas-oil plume migration behaviors by influencing the leakage amount. Water depth significantly affects gas-oil migration and the separation of gas plume and oil plume is gradually apparent as water depth increases. This study fills in the gap of ignoring the influence of flow pattern previously and is expected to help build more accurate emergency response guidelines. • A two-phase leakage and dispersion model based on coupled Eulerian-Lagrangian method is proposed. • The relative error between the predicted values and experimental values are within ±5% under stratified flow. • The relative error between the predicted values and experimental values are within ±10% under slug flow. • Leak location directly affects initial jet direction and leakage rate, thus affects the dispersion trajectory. [ABSTRACT FROM AUTHOR]