An improved air entrainment model for stepped spillways
Journal article, 2021

This work considers the application of the air entrainment model developed in [P. Lopes et al. Int. J. Nonlin. Sci. Num., vol. 18, pp. 559-574, 2017] to simulation of flows in stepped spillways. Four Froude numbers are considered for the flow, with parameters selected to match available experimental data. An extensive simulation campaign led to the identification of several deficiencies in the model, most importantly, its strong grid dependence. An improvement to the interface detection algorithm used in the model is proposed, and simulations reveal improved robustness with respect to the grid density. Furthermore, two criteria for predicting the inception point of air entrainment are tested, based on energy balance and boundary layer state, respectively. The boundary layer-based approach is recommended due to superior accuracy and robustness with respect to turbulence model selection.

Air entrainment modelling

Openfoam

Stepped spillway

Numerical modelling

Self-aeration

CFD

Author

Silje Kreken Almeland

Norwegian University of Science and Technology (NTNU)

Timofey Mukha

Chalmers, Mechanics and Maritime Sciences, Marine Technology

Rickard Bensow

Chalmers, Mechanics and Maritime Sciences, Marine Technology

Applied Mathematical Modelling

0307-904X (ISSN)

Vol. 100 170-191

Subject Categories

Applied Mechanics

Computational Mathematics

Fluid Mechanics and Acoustics

DOI

10.1016/j.apm.2021.07.016

More information

Latest update

9/15/2021