Sorting effect of bed material on suspended sediment in an open channel flow

Abstract

The classical equation for concentration distribution of suspended sediment in open channel flow is valid for both field and laboratory data, provided that the bed material is of uniform size. For heterogeneous bed material, prevailing integration methods do not take into account bed material sorting. In order to evaluate the role of this sorting in influencing relative concentration and mean size profiles of suspended sediment, an integration procedure is outlined which assumes that the sediment sizes (in ϕ units) are normally distributed. Numerical evaluation of the integration equation for selected input values of the relevant variables shows the importance of the sorting factor. The efficacy of this factor depends on the flow strength and mean size of the bed material. In general, the effect of sorting is most pronounced in the case of low flow strength and coarse bed material.

Keywords:

• Suspended Material
• bed Material
• flow regime
• sorting
• stream transport
• sedimentation
• experimental studies
• theoretical studies
• numerical analysis