DOI: 10.1615/TSFP8
INVESTIGATION OF WING STALL DELAY EFFECT DUE TO AN UNDULATING LEADING EDGE: AN LES STUDY
SINOPSIS
We present LES simulations of the flow over a wing
with sinusoidal leading edge undulations. The undulations
act as a passive flow control device, offering superior poststall aerodynamic performance relative to the unmodified wing with the same mean chord. The baseline case of a regular wing is also presented for comparison. In all cases the Reynolds number based on bulk velocity and mean chord is equal to 120, 000, and the angle of attack is set to 20°.
The study explores the details of the flow physics and
the mechanisms by which the post-stall aerodynamic benefit
is gained. For the particular set of geometrical and aerodynamic
parameters considered, a hitherto unreported physical
mechanism by which the undulation offers their benefit
is observed. This increased understanding of the flow
physics for the current configuration is an important step towards a more general understanding and the incorporation of the technology into practical designs. Potential applications include vertical axis wind turbines, unmanned air vehicles, helicopter blades, and canard surfaces; the present Reynolds number is of particular relevance to the first two of these applications.