Critical appraisal of various techniques used for velocity Distribution in open channel flow

Abstract

Distribution of velocity in the longitudinal as well as lateral velocity component is one of the basic aspects in open channel flow. It directly relates to various flow properties like shear stress distribution, secondary flows, surface profile estimation, channel capacity measurement and host of other flow entities. The knowledge of velocity distribution helps to know the velocity magnitude at each point across the flow cross-section. It has been found that velocity distribution in various types of channels varies with the shape, type and patterns of channels. In straight channel velocity distribution varies with different width-depth ratio, whereas in meandering channel velocity distribution varies with aspect ratio, sinuosity, meandering. Compound channel are all the way different and velocity distribution is a combination of flood plain and main channel (straight or meandering). It is found essential to study various methods used for accurate estimation of velocity distribution in various natural and artificial open channels. In the present work, critical appraisal of different approaches used for velocity distributions in channels are discussed. It has been found from the review that most commonly methods used by different researches globally are Prandtl , Theodore Von Kármán, Nikurádse,Coles because it is simple, robust and easy to use for computing velocity distribution in open channels.