FLOW PAST CIRCULAR CYLINDERS IN ERODIBLE CHANNELS

Abstract

A semi-theoretical analysis of "Flow Past Circular Cylinders in Erodible Channels" is presented in this thesis. The drag characteristics of cylinders, the afflux and the energy loss are inter-related to one another. Theoretical expressions for afflux and energy loss have been obtained using the basic equations of fluid mechanics, i.e. Energy,, Momentum and Continuity Equations. Reanalysis of the data collected by Hsieh(8), Pillai(16) and Rana(18) has resulted in a relationship for drag coefficient and an explicit method of computing afflux and energy loss for smooth as well as rough boundaries in case of cylinders placed in rigid-boundary channels. This relationship for drag coefficient has been used as the basis for analysing the effect of bed scour on the drag coefficient. An empirical relationship for the drag coefficient has been obtained using the experimental data collected during this study. The computed values of the afflux and energy loss using this value of drag coefficient agree reasonably with the observed values.