Effects of Stepped Chute Slope and Slit Location on a Jet from Abrupt Contraction Aerator
Publication: Journal of Hydraulic Engineering
Volume 150, Issue 2
Abstract
Under large unit discharges, stepped chutes are susceptible to cavitation damage due to lack of entrained air. Among various preaeration devices, the simple-structured abrupt contraction aerator (ACA) has a good performance on mild-slope () stepped chutes with a combined flow pattern consisting of a jet and a local hydraulic jump. To advance the understanding of ACA hydraulics, this paper investigates the effects of stepped chute slope and slit location on jet dynamics. A series of physical experiments were carried out on a steep-slope () stepped chute with varied slit locations. It was found that a jet was generated by ACA, and sufficiently aerated flow skimmed over the chute bottom with no black water, indicating an effective reduction of cavitation damage. The slit location had little effect on the flow patterns and aeration but might raise the flow profiles and enlarge the jet. Based on the experimental data, the empirical formulas for maximum height and distance of the jet are finally presented to provide references for sidewall design.
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Data Availability Statement
All data, models, and code generated or used during the study appear in the published article.
Acknowledgments
We acknowledge financial support from the National Natural Science Foundation of China (Grant No. 51979082).
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 150 • Issue 2 • March 2024
Copyright
© 2023 American Society of Civil Engineers.
History
Received: Mar 8, 2023
Accepted: Sep 24, 2023
Published online: Dec 6, 2023
Published in print: Mar 1, 2024
Discussion open until: May 6, 2024
ASCE Technical Topics:
- Aeration
- Cavitation
- Channels (waterway)
- Entrainment
- Flow (fluid dynamics)
- Flow patterns
- Fluid dynamics
- Fluid mechanics
- Freight transportation
- Geomechanics
- Geotechnical engineering
- Hydraulic contraction
- Hydraulic engineering
- Hydraulic properties
- Hydraulic structures
- Hydrologic engineering
- Infrastructure
- Slopes
- Stream channels
- Transportation engineering
- Water and water resources
- Waterways
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