الفهرس | Only 14 pages are availabe for public view |
Abstract Introduction: There are relatively few investigations for determining the effect of corrugated beds on the hydraulic jump characteristics, and it might be that there are no experimental and theoretical investigations to illustrate the corresponding downstream scour. The research problem: is to avoid the scour problem downstream hydraulic structures Aim of the Study: The following work concerns with the determination of the hydraulic jump properties over different shapes of bed corrugations and the characteristics of the corresponding downstream scour by using three different sand bed materials. These bed models were installed on the flume bed in such a way that the crests of corrugations were at the same level as the upstream bed on which the supercritical stream was produced by a sluice gate. The corrugations acted as depressions in the bed, to create a system of turbulent eddies and increased the bed shear stresses. A stream lined lip gate was used to prevent the action of vena contracta during the experimental work. Study procedure: 1- A steady flow of water is established through all experiments. 2- The tail gate is adjusted to ensure the formation of hydraulic jump. 3- The gate opening is considered to be the initial depth of jump and the point gauge used to measure the sequent depth of jump (y2), the length of jump is measured by ordinary scale. 4- The time used for making the scour hole at balance state is measured using stop watch. 5- The maximum depth of scour and the corresponding length are measured. |