Experiments on New Stilling Basins for Pipe Outlets

Abstract

This paper presents an experimental study on new stilling basins for non circular pipe outlet The new developed models were tested in a rectangular shaped pipe outlet of size 10.8cm x 6.3 cm with three inflow Froude numbers Fr = 1.85, 2.85 and 3.85 in comparison to USBR VI stilling basin model recommended for the pipe outlets. The new stilling basin models were developed by changing the shapes of the end sills of same height, while keeping the other configuration of stilling basin geometry same. To compare the performance of stilling basin models in different Froude numbers, the maximum scour depth and its location from end sill were measured for each model. The study indicates that due to changing the end sill geometry, scour pattern and hence the performance of stilling basin affected significantly.