Introduction


My research uses methods and ideas from non-linear physics to address problems in mechanical engineering. I generally study simplified systems that feature the physical phenomenon I am interested in. I use a combination of experimental, analytical and numerical tools.

Since the first of january 2024, I have moved to Institut Jean le Rond d'Alembert. Before that I spent a year in Fabian Brau's lab where I worked on fluid-structure interacton problems involving slender elastic structures and viscous flows. Before that I did another postdoc in Eva Kanso's lab where I worked on snap-through transitions in elastic solids. Before that, I did my PhD thesis at IRPHÉ where I worked on flame front dynamics under the supervision of Christophe Almarcha and Bruno Denet. Before that, I did my master thesis at LMFA where I worked on instabilities in Poiseuille flows with variable density under the supervision of Bastien Di Pierro and Marc Buffat. In case you'd like to know what happened before that, you can download my CV here

Research

Snap-through transitions

Boundary actuation of an Euler buckled beam


Snap-Through transitions occur when an elastic structure remains in an equilibrium configuration that suddenly ceases to exist or becomes unstable. The structure is then forced to "jump" to another equilibrium configuration through a brutal shape transition. This phenomenon is harnessed by different species in nature to generate large amplitude and fast motion. This is the case, for example, with venus flytraps and hummingbirds that harness this mechanism to trap their preys. While these transitions are known to be related to the type of bifurcation the system undergoes, there is no general understanding of the mechanisms that select these bifurcations. In this work, we address this problem by analyzing simple systems where an elastic strip is maintained in a buckled configuration and actuated by translating or rotating its boundaries.  


I was involved in this project under the supervision of Eva Kanso as part of my Postdoctoral research project in her lab.

Flame front dynamics

Propagation of a Propane-air flame in a Hele-Shaw cell


A premixed flame constitutes a self sustained chemical reaction that propagates through a gaseous reactive mixture. Under certain conditions, this reactive fluid dynamic problem can be reduced to an equation describing the dynamics of the reactive front. These simplified models provide a fundamental understanding of the physical mechanisms at play in premixed flame dynamics. However, a very few studies have performed quantitative comparisons between the dynamics described by these front equations and the one observed with experimental flames. One of the major difficulties is the three dimensional aspect of the reactive front that makes it difficult to analyze experimentally. In this work we address these questions by carrying experiments in a Hele-Shaw burner, an apparatus that makes the dynamics quasi bidimensional and allows to access the exact shape of the flame at every instant in time.  


I was involved in this project during my PhD thesis at IRPHÉ for which I was supervised by Christophe Almarcha and Bruno Denet
Collaborators : Joël Quinard, Elias Al Sarraf, Emmanuel Villermaux, Pedro Luis Garcia Ybarra, Juliette Piketty-Moine, Muhammad Tayyab, Pierre Boivin.

Publications

    2023

  1. Radisson B, Kanso E. Designing Shape Transitions in Elastic Structures. Journal of the Physical Society of Japan, 2023, vol. 92, no 12, p. 121010.    
  2. Kozyreff G, Siéfert E, Radisson B, Brau F The θ-formulation of the 2D elastica - Buckling and boundary layer theory. Proceedings of the Royal Society A, 479(2275), 20230087. On the cover    
  3. Battikh M, Al Sarraf E, Radisson B, Almarcha C, Denet B. Nonlinear dynamics of upward propagating flames. Physical Review E, 2023, vol. 107, no 6, p. 065110.    
  4. Radisson B, Kanso E. Dynamic behavior of elastic strips near shape transitions. Physical Review E, 2023, vol. 107, no 6, p. 065001.    
  5. Radisson B, Kanso E. Elastic snap-through instabilities are governed by geometric symmetries. Physical Review Letters, 2023, vol. 130, no 23, p. 236102. Editors' Suggestion    
  6. 2022

  7. Radisson B, Denet B, Almarcha C. Forcing of a flame by a periodic flow in a Hele-Shaw burner. Physical Review Fluids, 2022, vol. 7, no 5, p. 053201.    
  8. 2021

  9. Radisson B, Denet B, Almarcha C. Nonlinear dynamics of flame fronts with large-scale stabilizing effects. Physical Review E. 2021 Jun 11;103(6):063104.    
  10. 2020

  11. Radisson B, Denet B, Almarcha C. Nonlinear dynamics of premixed flames: from deterministic stages to stochastic influence. Journal of Fluid Mechanics. 2020 Nov;903.    
  12. Tayyab M, Radisson B, Almarcha C, Denet B, Boivin P. Experimental and numerical lattice-Boltzmann investigation of the Darrieus–Landau instability. Combustion and Flame. 2020 Nov 1;221:103-9.    
  13. 2019

  14. Radisson B, Piketty-Moine J, Almarcha C. Coupling of vibro-acoustic waves with premixed flame. Physical Review Fluids. 2019 Dec 24;4(12):121201.    
  15. Al Sarraf E, Almarcha C, Quinard J, Radisson B, Denet B, Garcia-Ybarra P. Darrieus–Landau instability and Markstein numbers of premixed flames in a Hele-Shaw cell. Proceedings of the Combustion Institute. 2019 Jan 1;37(2):1783-9.    
  16. 2018

  17. Almarcha C, Radisson B, Al Sarraf E, Villermaux E, Denet B, Quinard J. Interface dynamics, pole trajectories, and cell size statistics. Physical Review E. 2018 Sep 14;98(3):030202.    
  18. Al Sarraf E, Almarcha C, Quinard J, Radisson B, Denet B. Quantitative analysis of flame instabilities in a Hele-Shaw burner. Flow, Turbulence and Combustion. 2018 Oct;101(3):851-68.    

Resources


Here are some online resources that I found interesting and also a few documents related to my research.


-An article by Romain Brette about the general organization of research.
-A talk given by Marie Farge (in french) about scientific publishing.
- Marc Buffat's webpage (in french) for the interactive courses based on Python notebooks and other Arduino projects resources.
- Antoine Bérut's webpage for the very clear and convenient PhD thesis template in Latex and other interesting resources about Arduino, Python and his personal research.


-Here is a tutorial on how to drive a stepper motor in order to achieve a sinusoidal motion (using Arduino).
-Here is my PhD thesis manuscript: the first part is in French, the second is in Frenglish (sorry to both French and English speakers)...

Contact


Institut Jean le Rond d'Alembert
Campus Jussieu
4 place Jussieu
75005, Paris