Flip buckets are terminal spillway elements, generating free jets for energy dissipation. Deflectors are an alternative to flip buckets with constructional ease yet of similar hydraulic features. A first experimental study published at the 33rd IAHR Congress, Vancouver, investigated deflectorgenerated jets in terms of their air concentration characteristics. For jet impact onto a movable bed, the scour potential reduces as the jet air content increases. It was demonstrated that the jet air concentration development is a function of its relative black-water core length, depending on the approach flow parameters and the deflector geometry. Jet-generating structures are located at the end of spillways, where high-speed flow with considerable air transport prevails, affecting the jet parameters, such that additional experiments were conducted involving pre-aerated approach flow. The effect of pre-aeration on the air concentration development of deflector-generated jets is discussed and compared with un-aerated approach flow.
[1]
Willi H. Hager,et al.
Aeration Characteristics of Ski Jump Jets
,
2008
.
[2]
W. Hager,et al.
Ski Jump Hydraulics
,
2005
.
[3]
Willi H. Hager,et al.
Flip Bucket without and with Deflectors
,
2000
.
[4]
K. Lam,et al.
Hydraulic structures – I
,
2004
.
[5]
R. M. Khatsuria.
Hydraulics of Spillways and Energy Dissipators
,
2004
.
[6]
Da Ervine,et al.
BEHAVIOUR OF TURBULENT WATER JETS IN THE ATMOSPHERE AND IN PLUNGE POOLS.
,
1987
.
[7]
Hubert Chanson,et al.
Free-surface aeration and momentum exchange at a bottom outlet
,
2007
.
[8]
Willi H. Hager.
Uniform Aerated Chute Flow
,
1991
.
[9]
Willi H. Hager,et al.
Deflector Ski Jump Hydraulics
,
2008
.
[10]
Willi H. Hager,et al.
Hydraulics of Plane Plunge Pool Scour
,
2006
.
[11]
Alvin G. Anderson,et al.
Experiments on Self-Aerated Flow in Open Channels
,
1958
.