Jet-Forced Circulation in Water-Supply Reservoirs

A detailed understanding of the large-scale current motions in reservoirs is a fundamental prerequisite to their successful water quality management. A theoretical and experimental study of the throughflow-forced circulating flow within a reservoir gyre of simplified geometry is presented. Dimensional analysis and flow visualization are used to define the essential features of the flow. An integral-type mathematical model, containing no free parameters, is then presented and subsequently verified against laboratory experiments. This mathematical model is extrapolated to a real-reservoir parameter range to define a jet-forced circulation diagram. This diagram, which should be useful in the preliminary design of water-supply reservoirs, nondimensionally relates the jet-forced circulation to: (1) the reservoir aspect ratio and the boundary roughness; (2) the jet Reynolds number; and (3) the jet geometry having been shown to be relatively unimportant.