The Effect of Flow Diversion on Sediment Entering Intake Located at Section 52o in Sinuous Rivers

The outer bank in meandering rivers is suitable place for flow diversion. Flow diversion from the outer
bank of channel lead to formation of a transverse flow component having an opposite alignment with
the secondary current in bed and consequently transferring a part of the sediment bed load to intake.
The diversion of flow will change the flow pattern in the river bend and decrease the energy of the
secondary current in this location. In this paper the effect of flow diversion to sediment entering the
intake in a 52 degree diversion angle was investigated. The results have shown that the low ratios of
diverted flow has a little effect on the secondary current, and also this current causes the repelling of
sediments from the outer bend of the river. Along with the increase of the ratio of diverted flow, the
energy of secondary currents decrease and the ratio of sediment diversion increases. In a specific value
of flow diversion, the secondary flow was fully damped. After that, the sediments entering the intake
have a higher increase compared to the previous situation. The results also showed that the trend of
variations of diverted sediments with the flow diversion generally follows the S shape.