On the relevance of the Morton number on the hydraulic modelling of free-surface flows

This video emphasises the relevance of the Morton number on the hydraulic modelling of free-surface flows. Since air and water are most commonly used in hydraulic modelling of open channel and free-surface flows, the Morton number is an invariant. Its invariance simplifies the dimensional analysis by reducing the number of independent variables, including the elimination of the Weber number when the Froude and Reynolds numbers are retained.

Keywords: Free-surface flows, Open channel flow, Hydraulic modelling, Physical modelling, Computational modelling, Theoretical modelling, Morton number, Rose Katherine Morton, The Lady and the Bubble, Dimensional analysis, Similitude, Scale effects, Upscaling, Hydraulic structures, Froude number, Reynolds number, Weber number, Model-prototype compliance

Acknowledgements
Marie COLE
Prof Michael PFISTER
Ya-Hui CHOU

Bibliography
YouTube video clips by Hubert Chanson {   / @hubert_chanson  }

Froude number {   • Froude number  }
Reynolds number {   • Reynolds number  }
Weber number {   • Weber Number  }
Morton number {   • Morton number  }
Physical modelling in hydraulic engineering (3) Reynolds similitude {   • Physical modelling in hydraulic engineerin...  }
Physical modelling in hydraulic engineering (4) Froude similitude {   • Physical modelling in hydraulic engineerin...  }

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CHANSON, H. (2025). "The Morton number and its importance in free-surface flow modelling." Journal of Hydro-environment Research, IAHR, Review article, Vol. 62-63, Paper 100679, 6 pages (DOI: 10.1016/j.jher.2025.100679) (ISSN 1570-6443). {https://doi.org/10.1016/j.jher.2025.1...}