Variation of Flow Pattern with Sinuosity in Sine-Generated Meandering Streams

Abstract

The effect of channel sinuosity on flow pattern in meandering streams is investigated. The centerlines of the idealized meandering streams under consideration follow sine-generated curves, and the banks are rigid; the flow is turbulent and subcritical. This study focuses on the vertically averaged flow over a flat (horizontal at any cross section) bed formed by a granular material. The “flat bed” is viewed as the initial surface of a moveable bed at the beginning of an experiment (at time t=0 ). A series of laboratory flow measurements involving the systematic variation of the deflection angle θ0 from 30 to 110° , is used. It is found that every different sinuosity (every different θ0 ) has its own convective flow pattern, i.e., its own distribution in plan of (the L∕2 long) convergence–divergence zones of flow. As θ0 increases, a gradual change in flow pattern is observed. Two expressions defining the observed θ0 variation of the convective flow pattern are introduced. It is shown, with the aid of the se...