EXPERIMENTAL STUDY OF STILLING BASIN MODELS

Abstract

Stilling basins with appurtenances can be used effectively in dissipating the excessive energy downstream of hydraulic structure like spillway, sluices, pipe outlets etc. Experimental investigation leading to the development of new stilling basin model design for pipe outlet with different appurtenances is reported in this paper. On the basis of present study, newly stilling basin design has been compared with USBR VI model. The new models were tested in a rectangular shaped pipe outlet for three Froude numbers, namely Fr = 1.85, 2.85, and 3.85 in comparison to USBR VI stilling basin model recommended for the pipe outlets. The scour pattern was measured for each test run and flow pattern was also observed. The performance of the basin was compared by Performance number (PN) as criteria to evaluate the performance of model, using same sand base material and test run time for all the tested models. After test runs, it is found that, for a given Froude number range, the performance of new stilling basin model is improved and also the length of the newly developed basin is reduced as compared to USBR VI stilling basin for a given flow conditions.