Local and global stability of airfoil flows at low Reynolds number

Abstract

Previous direct numerical simulations of the flow around a NACA-0012 airfoil have observed the presence of three instability mechanisms: convective instability, a three-dimensional absolute instability of the naturally occurring vortex shedding, and an acoustic feedback instability involving sound production at the airfoil trailing-edge. In this study the behaviour and relative importance of these mechanisms are documented for a range of compressible low Reynolds number airfoil flows exhibiting laminar separation bubbles. © 2010 Springer Science+Business Media B.V.