KARAKTERISTIK ALIRAN TIDAK SERAGAM DENGAN SEDIMEN SUSPENSI PADA SALURAN TERBUKA

Abstract

The suspended sediment phenomenon has a close relationship with the water system in a river. The complexity of suspended sediment phenomenon, as well as the turbulence and non-uniformity of flow will cause differences characteristics from the uniform flow condition. The characteristics of suspended sediment of non-uniform open channel flow were studied using experimental method, by taking a direct measurement in the sediment-recirculating flume at the Hydrology and Hydraulic Laboratory of PS-IT UGM. The optical silt measuring instruments of Foslim-probe type was used for measuring the concentration distribution of the suspended sediment. While to measure the velocity distribution, electromagnetic flow meter probe set of VM-201H type combined with the vector calculation equipment of DV-101 type were used. Fifty series of measurements, which comprise of eighteen series of uniform flows, eighteen series of nonuniform decelerated flows, and fourteen series of non-uniform accelerated flows were obtained in this study. The result of this study shows that the integration constant value of the logarithmic-law, stated as Br, tends to be smaller than the Brvalue of clear water. The Br-value tend to increase with the increasing of pressure gradient value of non-uniform flow, n. The Coles wake parameter, , shows a similar trend with the Br-value, in which, the -value tend to increase with the increasing of n-value. The equation of Rouse, as well as, the equation of Tanaka and Sugimoto for uniform flow can predict the sediment concentration distributions of non uniform flow data satisfactory.