EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

A new mechanism for generating a bolus within a double layer following Scott Russell

Johan Fourdrinoy1, Julien Dambrine2, Madalina Petcu2,3,4, Morgan Pierre2, and Germain Rousseaux1
Johan Fourdrinoy et al.
  • 1Institut Pprime - CNRS, Université de Poitiers et Institut supérieur de l’aéronautique et de l’espace (ISAE-ENSMA), Poitiers, France
  • 2Laboratoire de Mathématiques et Applications, Université de Poitiers-CNRS, Poitiers, France
  • 3Institute of Mathematics of the Romanian Academy, Bucharest, Romania
  • 4The Institute of Statistics and Applied Mathematics of the Romanian Academy Bucharest, Romania.

While seeking to revisit an old experiment of John Scott Russell, we discovered a new mechanism for generating a non-shoaling bolus (an ovoid coherent mass of recirculating mixed fluids immerged in a surrounding medium/a of different density/ies) propagating along a pycnocline. In a study about dead-water (Fourdrinoy et al. 2020), a wave resistance phenomenon induced by internal waves formation at the interface between waters of different densities, we modified the setup used by Scott Russell. The Scottish engineer studied the formation and propagation of dispersive waves when an object is removed from a laterally confined open channel with a shallow layer of water. The “vacuum” created by the mass removal generates a linear dispersive free surface deformation with a front of negative polarity followed by a wave train. If we extend this configuration to a two-layers stratification, we can observe a linear dispersive wave with negative polarity à la Scott Russell, propagating along the interface. In addition, the removal of the object generates under certain conditions a bolus which induces a mixing zone and a gradient transition layer. We will present this new method of boluses creation, as well as an experimental characterization with space-time diagrams thanks to a subpixel detection procedure.

The dual nature of the dead-water phenomenology: Nansen versus Ekman wave-making drags.
Johan Fourdrinoy, Julien Dambrine, Madalina Petcu, Morgan Pierre and Germain Rousseaux.
Proceedings of the National Academy of Sciences, Volume 117, Issue 29, p. 16739-16742, July 2020.

How to cite: Fourdrinoy, J., Dambrine, J., Petcu, M., Pierre, M., and Rousseaux, G.: A new mechanism for generating a bolus within a double layer following Scott Russell, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-7301,, 2021.


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