Turbulent bluff-body wakes: stochastic dynamics and fluid-structure interaction
A/Prof Édouard Boujo
École Polytechnique (Paris, France)
Time & Place
Fri, 14 Sep 2018 16:00:00 NZST in E12, Level 2, Engineering CORE
All are welcome
Flows around non-streamlined (''bluff'') bodies have received a lot of attention in fluid mechanics. At low velocity (laminar regime), bluff body flows exhibit a series of bifurcations that are well understood from the fundamental viewpoint of dynamical systems and stability, and that are of practical interest for flow control. At higher velocity (turbulent regime), bluff body flows are usually more complicated, although some degree of coherence is still present. In this talk, I will show how the dynamics of turbulent wakes can be described with simple low-order models, where the effect of turbulence is taken into account via stochastic terms. Parameters are identified from experimental measurements, and model-based flow control becomes possible. I will also present recent results about stochastic fluid-structure interaction, when bluff bodies are free to rotate around an axis. In this situation, the body inclination and the wake orientation affect each other, and the overall dynamics can be described with coupled stochastic models.
Edouard Boujo received his M.Sc. in Vehicle Engineering from KTH (Royal Institute of Technology, Sweden). After working 3 years as an engineer in CFD and Aerodynamics at Nissan (Japan), he received his Ph.D. in 2014 in Mechanical Engineering from EPFL (Lausanne, Switzerland) and worked as a postdoctoral scientist at ETHZ (Zurich, Switzerland). From September 2018 he is assistant professor in Mechanics at École Polytechnique (Paris, France). His research interests include flow stability, flow control, adjoint methods, and more recently fluid-structure interaction. When not working, he usually enjoys rock climbing.