Bistability of a wind-swept pendulum

When exposed to a flow, a disk pendulum exhibits a bistability for a range of flow velocities. This comes from the change in predominancy between lift and drag in the aerodynamic forces applied to the pendulum, on both sides of the stall angle. This bistability disappears as the turbulence rate increases.

Work in collaboration with N. Plihon, M. Bourgoin (ENS de Lyon, France) and M. Obligado (LEGI, Grenoble, France).

Rare-event triggered transitions in Aerodynamics

In our experiment with the pendulum, we have observed spontaneous transitions in the bistable region. Inspired by the transition to turbulence, we developed a model to explain these transitions with rare events occuring in the wake, linked with stall.

Work in collaboration with N. Plihon and M. Bourgoin (ENS de Lyon, France).

Unstationnary effects on aerodynamical coefficients

In our experiment, if the pendulum is equilibrated, its trajectory from the vertical to the horizontal should reflect the aerodynamic coefficient angular dependency. Yet, we show that unstationnarity of the wake leads to great deviation from the static coefficient, with empirical added-mass and added-damping effects.

Work in collaboration with A. Gylfason (Reykjavik University, Iceland), N. Plihon and M. Bourgoin (ENS de Lyon, France).

Flight ObsErvation of Butterflies Under Space-like gravity

This project aims at the understanding of gravity influence on butterfly flapping motion.

Work in collaboration with L. Thorens (University of Oslo, Norway / ENS de Lyon, France), T. Basset, N. Plihon, M. Bourgoin (ENS de Lyon, France) and H. Liu (Chiba University, Japan).

Instability control through forcing

Distributed forcing over circular cylinder

We theoretically analyze the development of oscillatory flows behind a cylinder when a distributed forcing is applied.

Work in collaboration with N. Leoni (CEA Saclay, France) and D. Sipp (ONERA, France).

Plasma actuation on vehicles

We simulate how plasma actuators modify the wake of a vehicle depending on its position on the trunk and windshields.

Master internship under supervision of M. Tsubokura (RIKEN AICS / Kobe University, Japan).

Aurora Borealis

Auroras are one of the most mysterious phenomena happening regularly on Earth. Various experiments have been conducted to simulate the aurora in laboratory. We mounted a planeterrella to present to general audience how auroras are generated.

Work in collaboration with S. Vincent (ENS de Lyon, France).

Feather Aerodynamics

Feathers are exquisite airfoils that present no stall at any angle of incidence. This comes from aero-elastic properties that are yet to be investigated.

Non published article on the subject to be found here.

Dispersal of Individuals in ANimal Ecology

This project applies physical concepts from Lagrangian tracking to Animal Ecology using GPS tracks from open database.

Work in collaboration with T. Basset (ENS de Lyon, France).

Stork behavior in parental care

Storks build large circular open nests to take care of their off-spring. As such, their orientation when on the nest is not imposed by the shape of the nest. Through observations of a stork couple in Moselle (France), I show that the sun plays a determinant role on this orientation, while the wind is more discreet and only influences the orientation of the parent when rain is pouring.