Author(s): Vincent H. Chu, Wihel Altai
Linked Author(s): Vincent H. Chu
Keywords: Seawater desalination, negatively buoyant jet, fountain, density current, Lagrangian block advection
Abstract: A series of numerical simulations of the gravity-current head on the seafloor are conducted to study how the effluent from the seawater desalination plant is diluted so that strategy may be devised to minimize the impact of the effluent on the marine environment. In one simulation, the gravity-current head is produced by the release of the effluent from an instantaneous source. In the other simulation, the gravity-current head is produced by a continuous but intermittent source. The entrainment coefficient evaluated from the simulations of the gravity-current head, equal to a value of about 0. 11, is a nearly constant independent of the density stratification in the current head. Existing studies of the desalination effluent have been focused on the dilution of the effluent by the negatively buoyant jet in the near field. In the simulation, when the dense effluent is discharged vertically in the form of fountain, gravity-current heads are produced on the seafloor by the asymmetric and intermittent releases of dense effluent from the fountain. The part of the dilution by the current heads on the seafloor is found from the simulation to be the greater than the dilution within the fountain. The results of these series of simulations have pointed to the need of the simulation in the far field. The significant effluent dilution on the surrounding marine environment must be included for the optimal design of the desalination facilities
Year: 2017