Improving energy dissipation on stepped spillways using breakers

Abstract

Stepped spillways have many applications in dam structures, and river engineering. Moreover, stilling basins can be constructed with lower costs as energy dissipation by adding appurtenances to these stilling basins. This study aims to investigate the over-flow, through-flow, and under-flow breakers in stepped spillways and to evaluate their effect on energy dissipation. For this purpose, physical models of four steps were carried out on stepped spillways. Breakers were installed over the steps of spillway; the energy dissipation can be increased by different quantities, according to the characteristics of the breakers (height, width, arrangement of breaker heights and perforated holes). So studying the effect of the breaker on stepped spillway on the energy dissipation is very important issue. The dimensional analysis was used to correlate the different parameters affecting the studied phenomena. Comparison of flow energy dissipation over the toe of stepped spillway with breakers and classical stepped spillway shows that the stepped spillway with breakers type had dissipated more energy than the classical stepped spillway type. Keywords: Energy dissipation, Breaker, Stepped spillway