Bubble Plume Integral Model for Line-Source Diffusers in Ambient Stratification

Abstract

We developed an integral plume model to simulate the behavior of bubble plumes generated from line-source geometry in stratified ambient reservoirs by adapting the double-plume integral model developed for point-sources to a line plume. The model, based on top-hat velocity and buoyancy profiles, uses an Eulerian integral modeling approach and predicts the hydrodynamic, chemical, and thermodynamic behavior of the bubbles using a discrete bubble model. Existing integral models for line-source bubble plumes consider only the upward motion of bubbles and entrained water. To accurately predict intrusion formation, mixing patterns, and efficiency of bubble plumes in stratified environments, the downward flow of plume fluid from the maximum extent of plume rise to the trap height should also be included. To solve this problem, we presented a derivation of a continuously peeling double-plume model for line plumes and calibrated the model peeling factor to data for trap height in two stratified reservoirs. We applied the calibrated model to predict the gas transfer and vertical fluxes of oxygen from an oxygenation system in Carvins Cove reservoir and compared the predictions of the double-plume model to that using a standard single-plume model. We showed that the amount and the vertical distribution of entrainment into the plume differs in the double-plume model compared to the single-plume; hence, the type of model (double-plume or single-plume) would affect the results of simulations in coupled reservoir circulation models.