SCOUR CAUSED BY HYDRAULIC JUMP

Abstract

The present study aims at investigating the phenomenon of scour of loose sand bed downstream bf hydraulic jump which is formed over a rigid apron. In this study, different kinematic conditions•

downstream of the jump are produced to investigate t:he scour holes and t he.ir, deve.Loprnerit. The results obtained in this study indicate that:

(a) The shape and dimensions of the measured scour holes are dependent upon the kinematic and dynamic conditions of the stream at the end of the jump. (b) The scour profiles were found to be separately similar

according to the kinematic flow condition downstream of the jump. Two equations were developed to describe the relation among the length parameters of the scour hole. (cl The scour depth decreases with the increase of apron

length. Two relationships were developed to describe the experimental data. The scour depth depends also on .the turbulence intensity downstream of.the jump. (d) Razavan's formula is the most saiisfactory formula for estimating the maximum scour depth. (e) The flow structure at the roller zone of the jump affects the scouring process and the movement of the sand particles downstream of the jump.