Lecture

Flow Instabilities: Understanding Unstable Flows

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In course

ME-466: Instability

This course focuses on the physical mechanisms at the origin of the transition of a flow from laminar to turbulent using the hydrodynamic instability theory. ...

Description

This lecture covers various flow instabilities, including Vortex shedding, Saffman-Taylor, Flow separation, Tollmien-Schlichting, Rayleigh-Taylor, Lift-up and Streaks, Traffic waves, Meandering instability, Gravito-capillary waves, Taylor-Couette, Rayleigh-Plateau, Tearing instability, Rayleigh-Benard, Coiling instability, and Benard-Marangoni Kelvin-Helmholtz. The instructor explains methods to solve the Rayleigh equation, concepts of parallel flow instabilities, and the influence of viscosity on Kelvin-Helmholtz instability. The lecture also discusses the stability of plane Poiseuille flow and the influence of confinement on instability. MATLAB simulations and boundary layer analysis at increasing Reynolds numbers are demonstrated.

Instructor

François Gallaire

google scholar https://scholar.google.ch/citations?hl=fr&user=T3OooAcAAAAJ François Gallaire earned his engineering degree from Ecole Polytechnique in 1998 and a master's in Liquids Physics from Université Pierre et Marie Curie in 1999. He completed his PhD in 2002 at LadHyX on swirling flow instabilities and vortex breakdown. After six years at the Mathematics department of Université de Nice, he joined EPFL in 2009, founding the Fluid Mechanics and Instabilities Lab (LFMI). He became an associate professo

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