Air Bubble Entrainment in Breaking Bores: Physical and Numerical CFD Modelling
Language
en
Communication dans un congrès avec actes
This item was published in
7th International Symposium on Hydraulic Structures, 7th International Symposium on Hydraulic Structures, 2018-05-15, Aachen.
English Abstract
A positive surge or bore is an unsteady rapidly-varied open channel flow characterised by a rise in water surface elevation. After formation, the bore is traditionally analysed as a hydraulic jump in translation and its ...Read more >
A positive surge or bore is an unsteady rapidly-varied open channel flow characterised by a rise in water surface elevation. After formation, the bore is traditionally analysed as a hydraulic jump in translation and its leading edge is characterised by a breaking roller for Fr1 > 1.3-1.5. The roller is a key flow feature characterised by intense turbulence and air bubble entrainment. Herein detailed air-water flow measurements were conducted in breaking bores propagating in a large-size channel. The data showed a relatively steep roller, with a short and dynamic bubbly flow region. The results were used to validate a Computational Fluid Dynamics (CFD) model of breaking bores. The instantaneous void fraction and bubble distribution data showed systematically a lesser aeration region in the physical model, compared to the numerical data. The differences may be linked to some limitation of the CFD modelling.Read less <
English Keywords
Breaking bores
air bubble entrainment
computational fluid dynamics
CFD modelling
physical modelling
two- phase flow
unsteady flow motion
Origin
Hal imported