Ecology, Environment and Conservation Paper


Vol.18, Issue 1, 2012

Page Number: 171-176

EXPERIMENTAL INVESTIGATION OF THE EFFECT OF CHUTE ROUGHNESS HEIGHT ON ENERGY DISSIPATION

Mostafa Rahmanshahi Zahabi1 and Mahmood Shafai Bejestan2

Abstract

In this study the effect of bed chute roughness height on energy dissipation has been investigated. To do so first general non dimensional relation was developed, then a series of experimental tests were conducted in a physical model using three different bed slopes (15, 22.5 and 30 degree) and three different uniform roughness heights (1.1, 1.43 and 2.1cm). Total of 48 tests were conducted with flow discharges ranged between 15 and 45 L/sec. The results show that in comparison with the smooth bed, nearly 12 to 48 percent of the energy is dissipated on roughened bed chute. The results prove that the maximum energy dissipation occurs for slope of 22.5 degree and the minimum energy is dissipated on 30 degree chute.