Turbulent drag reduction downstream of large-eddy breakup (LEBU) devices is analyzed from the viewpoint of low-Reynolds number airfoil aerodynamics. It is argued that the variability of results between different research labs is primarily due to low Reynolds number “phenomena” associated with unsteady separation/transition of the LEBU device boundary layer. LEBU drag reduction is shown to be an extremely sensitive function of device micro-geometry at the low Reynolds numbers of all current investigations, and by analogy with conventional low-Reynolds number airfoil testing, the conclusion is drawn that the full potential for LEBU drag reduction must be explored at chord Reynolds numbers of 300,000 and above.
Large Eddy Breakup Devices as Low Reynolds Number Airfoils
Sae Technical Papers
SAE Aerospace Technology Conference and Exposition ; 1986
1986-10-01
Aufsatz (Konferenz)
Englisch