FLOW AROUND BEND IN OPEN CHANNEL

Abstract

Flow around bends, particularly in erodible channels, has caused much concern to hydraulic engineers since times immemorial. In natural rivers, the development of successive bends or meanders is an essential part of the process by which the river channel is •moulded whereas in artificial channels, bends are often necessitated due to topographic, unequal velo-city distribution, superelevation and energy losses. In this dissertation, an effort has been made to review the available literature on the subject and thus present uptodate knowledge on the subject in a concise form for ready use. General features of flow around bends and a brief his-torical resume of the work done on the subject are given in Chapter 1. The velocity distribution at bends is dealt with in Chapter 2. The superelevation at bends is dealt with in Cahpter 3. The energy losses at bends are dealt with in Chapter 4. The problem of flow separation and erosion in bends is dealt with in Chapter 5. Chapter 6 gives the principles which should be kept in view while designing beds in artificial channels to achieve maximum economy and efficiency. Some concluding remarks have been given in Chapter 7, summarising important observations made in the body. It is hoped that this dissertation will provide a valu-able review on the subject and help in better understanding of the phenomenon and of the principles to be followed in design-ing bends in artificial channels.