Large‐Eddy Simulation Model for the Effect of Gas Bubble Dissolution on the Dynamics of Hydrocarbon Plume from Deep‐Water Blowout

During a deep‐water wellhead blowout incident, the dynamics of the released hydrocarbon plume is strongly affected by the gas dissolution process that weakens the bubble‐induced buoyancy for driving the plume. In this study, a new modeling strategy is developed to efficiently incorporate the gas dissolution effect into a fast Eulerian‐Eulerian large‐eddy simulation (LES) model. By simultaneously simulating the evolutions of the bubble mass concentration and number density functions, the average bubble size in each LES computational cell can be calculated locally. Based on the cell‐averaged bubble diameter, the local gas dissolution rate and bubble rise velocity are parameterized, which are then used in the gas transport equations to model the evolution of the gas bubble field due to turbulent transport and gas dissolution. This LES model is applied to simulate several blowout scenarios with different initial bubble sizes. The results show that the plumes that have smaller initial bubble size exhibit faster relative bubble dissolution rate compared to the plumes with larger initial bubble size. As a result, the plumes with smaller bubbles also have lower peel and trap heights than those with larger bubbles. For comparison, a second set of LES runs with identical conditions but without including the gas dissolution effect are also performed. The data analysis shows that the omission of gas dissolution can cause overestimations of the plume peel and trap heights for up to 151 % and 127 % , respectively, suggesting the importance of including the gas dissolution effect for accurately modeling the near‐field hydrocarbon plumes.