Numerical simulation and analysis of initial plume discharge of deep-sea mining

Deep-sea mining involved environmental issues that urgently need to be addressed. The fine particle plume released from the surface vessel during deep-sea mining can impact the sea ecosystem, so investigating the characteristics of initial plume discharge is of significant importance for deep-sea mining systems. By numerical simulating the plume discharge process based on the two-fluid Eulerian model, this study explores the influence of initial discharge velocity, initial particle concentration, pipe diameter, and particle size on the surface plume discharge. The evolution mechanism of the plume is investigated through classic plume models involving the interaction of volume flux, momentum flux, buoyancy flux and the numerical simulation results exhibit a consistent trend with theoretical expectations. The results indicate that fine particle discharge velocity, discharge concentration, and pipe diameter are key influencing factors in plume evolution. The discharge velocity and pipe diameter primarily affect the evolution morphology of the plume through momentum flux and buoyancy flux. The discharge concentration mainly affects the plume's evolution through buoyancy flux.