Journal of Hydrodynamics

, Volume 30, Issue 4, pp 651–656 | Cite as

Dominant factor and incremental depth formula for self-aerated flow in open channel

  • Rui-di Bai (白瑞迪)
  • Fa-xing Zhang (张法星)
  • Wei Wang (王韦)
  • Shanjun Liu (刘善均)Email author


The presence of air in open channel flows will increase the bulk of the flow, and is of great importance in the design of spillway and chute sidewalls. Hydraulics in the developed region is investigated in this paper systematically by a series of model and prototype investigations. It is verified that the velocity in the aeration region is the dominant factor. For the flow with an identical velocity but a different flow depth, the air concentration distributions are nearly the same. From the theory based on the formation of drops on the surface by the turbulent liquid jets and the vortex deformation, a formula to calculate the incremental depth is obtained by best correlating the model and prototype investigations. The formula is reasonable with less mean error than those obtained by other methods, which could recommended for the use in engineering designs.

Key words

Aerated flow aeration incremental depth unaerated black water aeration flow depth 


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Copyright information

© China Ship Scientific Research Center 2018

Authors and Affiliations

  • Rui-di Bai (白瑞迪)
    • 1
  • Fa-xing Zhang (张法星)
    • 1
  • Wei Wang (王韦)
    • 1
  • Shanjun Liu (刘善均)
    • 1
    Email author
  1. 1.State Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengduChina

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