Sedimentation from particle-bearing plumes in a stratified ambient

Laboratory experiments are performed to examine the sedimentation of particles that initially rise in a plume, then spread radially and settle in uniformly stratified fluid. Using light attenuation, the depth of the sediment bed is measured nonintrusively as a function of radius from the center of the plume. To gain some insight into these dynamics, an idealized model is developed by adapting well-established plume theory and a theory that accounts for sedimentation from surface gravity currents emanating from a plume impacting a rigid lid. We also account for recycling of falling particles that are re-entrained into the plume. With a suitable choice of parameters determining the intrusion height, entrainment during fountain collapse, and the radius at which settling from the intrusion begins, in most cases for which particles are predicted to be drawn back into the plume and recycled. The predictions for intrusion height, particle mound height, and spread agree within 20% of observations.