Active Flow Control pp 281-292 | Cite as
Active Management of Entrainment and Streamwise Vortices in an Incompressible Jet
Abstract
A pilot experimental investigation was conducted to study the active generation and management of streamwise vortices in an incompressible jet flow. The lip of the jet was equipped with small flaps (flaplets) deflected away from the stream at 30°, that incorporated flow control slots through which steady suction and zero mass-flux perturbations were introduced. Control via suction, reduced the pressure on the flaplets, thereby entraining fluid from the surrounding fluid and generating streamwsie vortices. Flaplet length had very little effect on the vortex formation but exerted a profound influence on the dissipation of the vortices further downstream. Jet momentum could also be increased by up to 25%. Preliminary experiments using zero mass-flux control indicated that entrainment of the surrounding fluid was combined with a reduction of momentum in the jet.
Keywords
Particle Image Velocimetry Shear Layer AIAA Paper Vortex Generator Streamwise VortexPreview
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