Plants are living beings interacting mechanically with the external environment (bending because of wind, growing in a gravity field, moving by creating mechanical forces, etc.) I apply tools of solid mechanics and fluid mechanics to plants. The goal is to better understand plants' strategies, behaviours, optimality, sizes towards external stresses.
My PhD thesis focuses on the interaction between wind and tree foliage. How does foliage move for a given wind velocity ? This interaction is critical for plant development, agronomy, crops and forest management, because there are noticeable winds (> 1 m/s) more than 80% of the time on earth.
E. de Langre, M. Saudreau, P. Hémon, C. Derloughian, T. Barois, B. Darbois-Texier.
Data acquisition : tree in a wind tunnel credits: CNRS
Plants in wind: state of art and concerns credits: École Polytechnique
This field of research is mainly curiosity driven. It appears that regarding the burst of a red blood cell or the reverse swing of a cricket ball in air, fluid-solid interaction matters. I have being studying a model system at low Reynolds number to understand red blood cells bursting after malaria infection. However these last years, I focused on fluid-solid interaction at large Reynolds number (wind in trees, reverse swing of the cricket ball).
E. de Langre, P. Hémon, T.Andrianne, D. Cuvelier.
Bouncing droplet: Wave-Particle duality
I am conducting experimental investigation on bouncing droplets at the University of Liège, under FNRS Chargé de Recherche status. A decade ago, Yves Couder found a model system exhibiting properties reminiscent of the wave particule duality. This model system is compounded of a droplet bouncing on a vibrated bath of the same fluid. There is no coalescence between the droplet and the fluid bath, however the over pressure created by the droplet onto the fluid bath create waves. Those waves interact with the droplet and propel the droplet.
T. Gilet, P. Schlagheck, Jeong-Bo Shim and N. Sampara.
Impacts in biology
I am currently launching this research area. I started thinking about this subject when a rugby team mate was left unconscious on the field after an impact at the head. This raises the brain concussion problem in sports but in fact the problem of impacts in biology is much wider: the noise of a tree in wind is due to impacts of leaves ones onto the others, sports ball are designed to avoid muscles and body injuries, some animals use head impacts to asses social ranking during the mating season, bearded vulture open bones by impacting them onto rocks. Examples are numerous.
B. Darbois-Texier, C. Cohen.