Effects of Meandering in Alluvial Streams

It was found that for a given mean depth and velocity of flow, the sediment discharge per unit width in the full-width meandering channel was greater that that in the straight flume, which in turn was greater than that of the half-width meandering channel. The bend-loss coefficient, defined as the head loss (plus or minus) due just to channel curvature normalized by the mean-velocity head, increases with Froude number, the ratio of bed hydraulic radius to median sand diameter, and the ratio of width to center line radius of curvature. At the smaller depths investigated, the friction factors of the sinuous channel flows are less than those of the straight channel flows. These effects apparently result primarily from the large changes produced in the bed configurations by the secondary flows.