MATHEMATICAL MODELLING OF ALLUVIAL - RIVER WITH SECONDARY FLOW

Abstract

The influence of secondary flow in reshaping the geometry of the sinuous alluvial rivers cannot be under-emphasised. Secondary flow though exists in channels of both linear and non-linear alignment, as the flow enters into a bend, secondary flow induced by the centrifugal force becomes very pronounced. The spatial variation of the transverse velocity is related to centifugal acceleration, superelevation of transverse water surface and channel roughness etc. The secondary flow also causes significant variation in flow resistance and corresponding energy expenditure. Based on the above concept, a model has been formulated to simulate the temporal and spatial variation of hydraulic and geometric p bperties of alluvial streams. The model is founded on the gradually varied flow equations of de Saint venant and makes use of the uncoupled solution method......