Evaluation of tunnel sidewall boundary-layer-control systems for high-lift airfoil testingAn experimental study was conducted in the NASA Langley Low-Turbulence Pressure Tunnel to evaluate a suction sidewall boundary-layer-control (BLC) technique used in testing 2D high-lift airfoils. Sidewall BLC is required to maintain spanwise two-dimensionality of the flow over the airfoil at large angles of attack. A supercritical-type high-lift air-foil, equipped with a double-slotted flap and a leading-edge slat, was used for the study which was conducted at a Mach number of 0.2 and Reynolds numbers based on chord of 9 and 16 million. The sidewall BLC technique, which features distributed suction through porous endplates connected to a venting system, was able to control sidewall boundary-layer separation and maintain two-dimensional flow over the high-lift configuration for both Reynolds numbers tested. Discussions on porous endplate optimization and effects of suction on section lift are presented. Results obtained with the suction system were also compared with previous data obtained with a tangential blowing BLC system for the same high-lift configuration.
Document ID
19910069243
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Paschal, K. (NASA Langley Research Center Hampton, VA, United States)
Goodman, W. (NASA Langley Research Center Hampton, VA, United States)
Mcghee, R. (NASA Langley Research Center Hampton, VA, United States)
Walker, B. (NASA Langley Research Center Hampton, VA, United States)
Wilcox, Peter A. (Douglas Aircraft Co. Long Beach, CA, United States)