SEARCH Articles Figures Tables Hopper and Standpipe Flow Theories Hopper and Standpipe Flows Hopper-Standpipe-Discharger Flow Leakage Flow of Gas in a Standpipe Multiplicity of Steady Standpipe Flows Standpipe Standpipes fluidized flow Standpipes in Fluidized Bed Flow Standpipes in Packed Bed Flow