Large-eddy simulation of small-scale ocean turbulence coupled with buoyant plumes

To examine the turbulent characteristics of a small-scale ocean (length scale at L= 0(10(3) m)) disturbed by buoyant plumes, a numerical experiment is performed by employing Large-eddy simulation technology and two-fluid theories. This includes a simulation of reconstruction of the statistically stationary state of a small-scale ocean and the simulation of two-fluid plumes. For numerical reconstruction of a small-scale ocean, the observation data of the instantaneous flow field on the West Coast of Hawaii Island is applied to the determination of the turbulent structure with the aid of the forced-dissipative mechanism. The dynamics of buoyant droplets is described by an Eulerian scheme with the assumption of treating the droplets as a quasi-fluid. The two-way coupling between turbulent ocean and droplets is performed through exchange sub-models for momentum and mass. The predictions of turbulence spectra indicate that the buoyant plumes improved indistinctly the horizontal turbulent characteristics, however, they significantly modified the temperature spectrum in the lower wavenumber range. For plumes, the dynamics in the regime near the injection exit are dominated by interactions between turbulent ocean and droplets/solution. Outside of this regime, water column of solution is governed by the ocean turbulent flow.