An Eulerian large eddy simulation model of deep-sea oil/gas plumes with gas dissolution effect

During a deep-sea oil wellhead blowout accident, the oil/gas mixed plume rises through the ocean driven by the buoyancy induced by gas bubbles. As the plume rises, it continuously loses its driving force as gas bubbles are dissolved by the ambient sea water. Accurately modeling the effect of gas dissolution is thus crucial for understanding plume dynamics and predicting the oil dispersion, which are key pieces of information needed for planning oil spill remediation. In this study, a fast Eulerian large-eddy simulation (LES) approach is used to model the effect of gas dissolution on plume dynamics. By simultaneously simulating the evolutions of the bubble mass concentration function and the number density field, the average bubble size in each LES computational cell can be calculated locally. Based on this information, the local gas dissolution rate and bubble rise velocity are computed, which are then used in the gas transport equations. This fast Eulerian LES model can capture the effect of gas bubble dissolution on the macroscopic plume characteristics with reasonable computational cost. In this talk, some preliminary results for LES of deep-sea hydrocarbon plume blowout are presented.