Flow over fluvial bedforms with suction

Abstract

Development of bedforms is studied in curvilinear sand bed threshold channel with uniform sand (d50 = 0.418 mm). In this study, two types of experiments have been carried out no seepage (NS) and with downward seepage or suction (WS). Present experimental study investigates the development of bedforms and turbulent characteristics in a threshold channel after applying the suction. Value of bed shear stress measured at temporal basis with suction initially increases with time. Once the channel attains near stability with application of seepage, Reynolds stresses decrease. Measurements have shown that turbulent intensities initially increased due to seepage and reduced when channel was subjected to downward seepage further, which probably shows that migration rate of bedforms is reduced. Features of bedforms geometry start with small in size in which they propagate from upstream to downstream.