مدل رياضي يك بعدي محاسبه دبي جريان در سدهاي سنگريزه اي تاخيري مستغرق

One Dimensional Mathematical Model for Discharge Flow Calculation in Submerged Rockfill Detention Dams.

For non-Darcy flow in submerged porous media a one- dimensional mathematical model has been developed. Rockfill detention dams are one of these porous media that comprised of relatively homogenous coarse rockfill which can be used to reduce flood discharge and hydrograph peak. In this research the focus was on the rockfill detention dams in submerged condition. The existence of overtopping rockfill dams flow, seepage flow and the potential momentum of material made investigation through and overtopping phenomena very complicated. Flow through and over rockfill detention dams can be investigated in three zones including open channel flow (main channel), normal seepage zone (non-Darcy seepage low) and transition zone. In this research, at first the governing equation in each zone has been developed individually. These equations combines with boundary condition and then the main governing equation in rockfill detention dams in submerged condition was achieved. A comparison between computed and experimental results was then made on the basis of two physical model performances in the hydraulic laboratory of the University of Tarbiat Modares. The physical model were collected from a rockfill dam of 300x300x600mm dimension (widthxdepthxlength) with rock average diameters of 10-20mm installed in atilting flume of the hydraulic laboratory. At the end an investigation between another researcherʹs relation and results was made on the basis of amount of flow through rockfill detention dams and the best relation was selected.