Dynamic Actuation for Delta Wing Post Stall Flow Control

Abstract

The manipulation of delta wing flow by active and passive flow control methods is of great interest for increasing the performance (e.g. lift enhancement) of such configurations. This work presents experimental results in the post-stall regime at very high angles of attack (α = 35-45• ) on a 65• sweptback generic half delta wing configuration (VFE-2 geometry) with sharp leading edge using slot actuators for pulsed blowing along the leading edge. The study comprises results of force, velocity and pressure measurements and substantiates the receptivity of the shear layer for the pulsed excitation. For α = 35• , an actuation at F + ≈ 2.7 effects a retardation of vortex breakdown. For α = 45• , the optimum pulse frequency was found at F + = 1.0-1.5, which leads to the re-establishment of a burst vortex and a significant increase in lift, thus satisfying the aim of enhancing aerodynamic performance.