Significance of Shape Factor of Obstacle on Local Scour

Abstract

The main goal of this research was to determine the effect of shape factor of obstacle on local scour. The research aimed at better quantification of local scour depth with respect to obstacle shape and bed material variations. The shape factor has been defined as a ratio of scour of any shape to the scour of circular shape under similar conditions. Four different shapes and five different bed materials were used in the study. The shape factors were computed for all the shapes in each bed material used, and the shape factor for a particular shape was found to remain almost unaffected for different bed materials and the flow parameters. On the basis of this research work, a relation was developed for the estimation of local scour, taking into account the effect of shape factor along with other factors responsible for the scour phenomenon. The model so developed was validated for different bed materials and different obstacle shapes with the help of Breusers model.