A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Sheets of water discharging freely from long weirs or spillways such as those on dams raised by stressing cables may exhibit the undesirable phenomenon of nappe oscillation, unless split at frequent intervals by suitable splitters. Tremendous noise is generated and structural damage to mechanical appurtenances may result where the water spills over crest gates. A theory is advanced to show that the air beneath the nappe vibrates at one of a particular set of frequencies, depending on certain nonlinear characteristics. Some aspects of the mechanism are examined in detail and it is shown that a range of possible frequencies can be determined if the initial velocity, height of fall, and angle of projection are know. The influence of damping is briefly examined.
Sheets of water discharging freely from long weirs or spillways such as those on dams raised by stressing cables may exhibit the undesirable phenomenon of nappe oscillation, unless split at frequent intervals by suitable splitters. Tremendous noise is generated and structural damage to mechanical appurtenances may result where the water spills over crest gates. A theory is advanced to show that the air beneath the nappe vibrates at one of a particular set of frequencies, depending on certain nonlinear characteristics. Some aspects of the mechanism are examined in detail and it is shown that a range of possible frequencies can be determined if the initial velocity, height of fall, and angle of projection are know. The influence of damping is briefly examined.
Nappe Oscillation
Schwartz, H. Ivan (author)
Journal of the Hydraulics Division ; 90 ; 129-143
2021-01-01
151964-01-01 pages
Article (Journal)
Electronic Resource
Unknown
| Engineering Index Backfile | 1964
Discussion of “Nappe Oscillation”
| ASCE | 2021
Discussion of “Nappe Oscillation”
| ASCE | 2021
Closure to “Nappe Oscillation”
| ASCE | 2021
Finite Crest Length Weir Nappe Oscillation
| ASCE | 2018