Experimental Investigation of the Effect of Chute Bed Roughness Height on Energy Dissipation

In this study the effect of chute bed roughness height on energy dissipation has been investigated. To do so first general non dimensional relationship was developed. Then series of experimental tests were conducted in a physical model using three different bed slopes (15, 22.5 and 30 degrees) 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 lit/sec. Results show that in comparison with the smooth bed, nearly 12 to 48 percent of the flow energy was dissipated on the roughened bed chute. Maximum energy dissipation occured for slope of 22.5 degrees and the minimum energy was dissipated on 30 degrees chute. A relationship was developed for prediction of energy slope on this type roughened bed chutes and the results obtained were compared with the results of previous works.