Experimental study of the dynamic scour plunging pool under submerged circular jet

One of the most important issues in the river hydraulics is scour prediction due to impact of dams and flood drainage systems or water jet discharged from the outlet of the cooling systems of nuclear power plants to the river bed. Several factors contribute to the formation of scour holes which include the nozzle diameter, jet velocity, tailwater depth, grain size distribution of bed material and jet height from the river bed or plunge pool. In this paper using the experimental study, static and dynamic dimensions of scour were studied by changing jet height from to the bed material and grain size distribution, in the area under this study, The results show that the relative static scour depth against erosion parameter are defined in this study has the slope of the ten percent. Also used laboratory observations and analysis of the results showed that the relative difference dynamic and static scour depth is directly related to the Froude number. Depending on the jet height from the alluvial bed, Dynamic scour depth is an average 2.6 times than static scour.