Inception Point Relationship for Flat-Sloped Stepped Spillways
Publication: Journal of Hydraulic Engineering
Volume 137, Issue 2
Abstract
A two-dimensional, physical model was constructed to evaluate the air entrainment inception point location in a 4(H):1(V) stepped spillway. Step heights of 38, 76, and 152 mm were evaluated. The physical model was constructed with a broad-crested weir, and model unit discharges ranging from to were tested. Hubert Chanson developed a relationship for predicting the inception point location for primarily steep stepped spillways. In this study, Chanson’s relationship effectively predicts the location of the inception point for slopes as flat as 14° for Froude surface roughness values which, in this study, corresponds to model step heights of 38 and 76 mm. A new relationship for predicting the location of the inception point was developed, applicable for flatter sloped stepped spillways with . This relationship is similar to Chanson’s, but it is optimized for flat-sloped stepped spillways with a broad-crested weir.
Get full access to this article
View all available purchase options and get full access to this article.
References
Boes, R. M., and Hager, W. H. (2003). “Two-phase flow characteristics of stepped spillways.” J. Hydraul. Eng., 129(9), 661–670.
Chamani, M. R. (2000). “Air inception in skimming flow regime over stepped spillways.” Proc., Int. Workshop on Hydraulics of Stepped Spillways, H. E. Minor and W. H. Hager, eds., Balkema, Rotterdam, The Netherlands, 61–67.
Chanson, H. (1994). “Hydraulics of skimming flows over stepped channels and spillways.” J. Hydraul. Res., 32(3), 445–460.
Chanson, H. (2002). Hydraulics of stepped chutes and spillways, Balkema Publishers, Steenwijk, The Netherlands.
Chanson, H., and Toombes, L. (2002). “Experimental investigations of air entrainment in transition and skimming flows down a stepped chute.” Can. J. Civ. Eng., 29, 145–156.
Hunt, S. L., and Kadavy, K. C. (2010a). “Energy dissipation on flat-sloped stepped spillways: Part 1. Upstream of the inception point.” Transactions of ASABE, 53(1), 103–110.
Hunt, S. L., and Kadavy, K. C. (2010b). “Energy dissipation on flat-sloped stepped spillways: Part 2. Downstream of the inception point.” Transactions of ASABE, 53(1), 111–118.
Takahashi, M., Gonzalez, C. A., and Chanson, H. (2006). “Self-aeration and turbulence in a stepped channel: Influence of cavity surface roughness.” Int. J. Multiphase Flow, 32, 1370–1385.
Wood, I. R., Ackers, P., and Loveless, J. (1983). “General method for critical point on spillways.” J. Hydraul. Eng., 109(2), 308–312.
Information & Authors
Information
Published In
Copyright
© 2011 ASCE.
History
Received: Aug 13, 2009
Accepted: Jul 6, 2010
Published online: Jul 10, 2010
Published in print: Feb 2011
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.