Sediment Transport in Unsteady Flows

摘要

The hydraulic and sediment transport response of open channel flow to unsteady flow conditions is investigated both theoretically and experimentally. The characteristics of a sand bed exert a profound influence on long term channel stability and short term flood routing in natural alluvial channels. The mathemantical formulation of the equations governing flood propagation in channels with movable beds is examined and the importance of individual terms under various flow conditions are discussed. A numerical algorithm for the solution of the governing equations is developed, based on the method of characteristics. This model solves the full coupled system of equations and is appropriate for studying short term flood routing. All sediment transport models require concentration and friction expressions for closure of the problem.