Author(s): Bombar G.; Guney M. S.
Linked Author(s):
Keywords: Stepped spillway; Cine Dam; Model scale effect; Inception point of air entrainment
Abstract: With the evolution of the Roller Compacted Concrete (RCC), the stepped chute is integrated to the dam, so the body itself could be used as the spillway. In Turkey, Cine and Caltikoru Dams are the examples of RCC dams. In this study, the flows over stepped spillways are examined. A 1/10 scaled partial model of Cine Dam’s spillway obeying the Froude Similitude Law is constructed in DEU Hydraulics Laboratory. Experimental studies are performed both on the formerly constructed 1/100 scaled model in DEU Hydraulics Laboratory and on 1/60 scaled model in Hydraulics Model Laboratory of DSİ. The experiments carried out on the 1/30 scaled partial model (Darama, 2001) are also considered. The various flow regimes and the onset of skimming flow are investigated. The non-aerated water length from the spillway crest to the point of inception (Li) is measured. The results are compared to those obtained by other researchers. The scale effect on the Li parameter caused by neglecting the surface tension forces is investigated by considering the 1/10 scaled partial model as a sub-prototype, and the results are compared with a similar study done by Tozzi (1992). An empirical formula is derived to predict probable Li values specific to Cine Dam.
Year: 2007