Apparent Shear Stress in An Unsymmetrical Compound Channel Flow

Abstract

When the river has two equal adjacent flood plains on both sides of it, is known symmetric compound channel otherwise it is called as unsymmetrical compound channel. In an unsymmetrical compound open channel flow, much of the hydraulic resistance may be ascribed by channel and flood plain geometry, roughness and flow characteristics with other factors. An expression to predict this boundary shear distribution in its unequal flood plains has been presented. From this expression, the apparent shear at vertical interface can easily be perceived. However, the precise prediction of apparent shear at junctions becomes arduous when the river is unsymmetrical instead of a symmetric one. The inequality of apparent shear force prevailing at the junctions of an unsymmetrical compound channel has been quantified in terms of apparent shear stress ratio. The consequence of the analysis for predicting the apparent shear stress ratio is analyzed through some natural river data sets. Moreover, the current approach is also capable of quantifying the intensity of momentum transfer at both the vertical interfaces and for computation of individual flood plain discharge by reasonable accuracy.