THE EFFECT OF ANGLE ON SEDIMENT DISTRIBUTION IN CANAL OFF-TAKES

Abstract

This thesis reports the experimental studies conducted to investigate the effect of the angle of offtake en sediment distribution in channels. The main channel flume was 3 feet wide and 20 feet long and the offtake channel was 15 2n. wide. give different offtake angles 30°, 60°, 900, 120° and 1500 were studied with a fixed quantity of s ediment fed at the head of the parent channel for three channel discharges. At very low discharge when the sediment movement was insigniw ficant, red beads were used to get an idea of sediment distribution pattern. It was found that the 300 offtake angle was the most efficient in comparison with the other angles studied. It was also observed that the sediment shared by the offtake channel was not in proportion to the quantity of water allowed in the offtake. In all the cases, the sediment share in off-take was more than the discharge shared by the pAftake. The existence of a centrifugal force at the offtOge has been verified which was least for the angle of 30° at 10% discharge of the parent channel. #