AN EXPERIMENTAL STUDY ON PERFORMANCE OF SKIJUMP BUCKET

Abstract

The skilump bucket.- is a relatively low cost device for energy dissipation below spillways where tailwater depth is deficient for hydraulic jump. As it creates scour at the point of impact of jet, its use is normally recommended only where sound bed is available. To make use of economy available with the skijump buckets, it may be worth considering if its use can be extended to cases where the bed rock may not be very sound. In order to do so, It is necessary to have an idea of the probable maximum scour that would occur. Only a limited amount of work has been done on this problem so far. The present experimental study Is a step in that direction. Model studies have been carried out on -a model of height 27.61nahes from invert to crest. The bucket radius was 11.4© inches and lip angle was 3+-.3O'. The model profile was not changed during the experiments. The variables studied were, the discharge intensity, the river bed level in relation to lip and the tailwater depth. The model data has been compared with available prototype data as well as earlier model data. A dimensionless correlation has been obtained for the present model is as follows: z------ gz3:dm2 )*