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HYBRID LAMINAR FLOW CONTROL TESTS IN THE BOEING RESEARCH WIND TUNNEL
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Abstract
This paper describes a program of wind tunnel tests of the hybrid laminar flow control (HLFC) concept at near full scale Reynolds number. The tests were performed in the low speed 5′ X 8′ Boeing Research Wind Tunnel on a large (20 Foot Chord) section of an infinite swept wing having a sweep angle of 30°degrees. Boundary layer suction was provided over the first 20 percent chord on the wing upper surface through an electron beam perforated titanium suction surface. The extent of laminar run beyond the suction region on the wing surface was measured for various external pressure distributions and suction distributions. Two transition detection techniques were employed: an off-the-surface-pitot and a relocatable hot film. Depending upon the external pressure distribution the laminar run extended as far back as 45 percent chord. This corresponds to a transition Reynolds number of approximately 11 x 106. Significant spanwise non-uniformity of the transition location was encountered at “off-design” model incidences. This was caused by spanwise non-uniformity of suction induced by spanwise external pressure gradients. For given chordwise pressure distribution and Reynolds number conditions, the maximum chordwise extent of laminar run was found to be insensitive to the suction level over a wide range.
Evidence of “aerodynamic roughness” induced transition was found under strong suction applied through multiple rows of discrete holes.
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Parikh, P., Lund, D., George-Falvy, D., and Nagel, A., "HYBRID LAMINAR FLOW CONTROL TESTS IN THE BOEING RESEARCH WIND TUNNEL," SAE Technical Paper 901978, 1990, https://doi.org/10.4271/901978.Also In
References
- Wagner, R. D. Maddalon D. V. et. al. Fifty Years of Laminar Flow Flight Testing SAE Aerotech '88 Conference Anaheim, Ca. Paper No. SAE 88-1393 October 1988
- Wagner, R. D. Maddalon D. V. Fisher D. F. Laminar Flow Control Leading - Edge Systems in Simulated Airline Service Journal of Aircraft 27 3 March 1990
- Boeing Commercial Airplane Co. Evaluation of Laminar Flow control System Concepts for Subsonic Transport Aircraft NASA CR 158976 December 1978
- George-Falvy, D. Laminar Flow Test Installation for the Boeing Research Wind Tunnel AIAA 16th Aerodynamic Ground Testing Conference Seattle, Wa. June 1990 AIAA Paper No. 90-1425
- Anderson, B. T. Meyer. R. M. Effects of Wing Sweep on Boundary Layer Transition for a Smooth F-14A Wing at Mach Numbers from 0.7 to 0.825 (Glove I) NASA TM 101712 May 1990
- Pfenninger, W. Laminar Flow Control Laminarization AGARD Report No. 654 June 1977
- Boeing Commercial Airplane Co.: Hybrid Laminar Flow Control Study Final Technical Report, NASA CR 165934 October 1982
- Giles, M. B. Drela M. Two Dimensional Transonic Aerodynamic Design Method AIAA Journal September 1987
- Magnus, A. E. Epton M. E. PANAIR-A Computer Program for Predicting Subsonic Linear Potential Flows about Arbitrary Configurations using a Higher Order Panel Method NASA CR 3251 April 1980
- Dryden, H. L. Combined Effects of Turbulence and Roughness on Transition IX 249 258 1958
- Rozendaal, R.A. Behbehani R. Variable Sweep Transition Flight Experiment (VSTFE)-Unified Stability System (USS) Description and User's Manual NASA CR-181918 July 1989
- Goldsmith, J. Critical Laminar Suction into an Isolated Hole of a Single Row of Holes Northrop Report NAI-57-529 or BLC-45 February 1957