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Effect of Wing Planform and Canard Location and Geometry on the of a Close-Coupled Canard Wing

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Effect of Wing Planform and Canard Location and Geometry on the of a Close-Coupled Canard Wing AND NASA TECHNICAL NOTE NASA TN D-7910 o-J WING PLANFORM N75-23514 -- (NASA-TN-D-7910)- EFFECT OF AND CANARD LOCATION AND GEOMETRY ON THE LONGITUDINAL AERODYNAMIC CHARACTERISTICS OF A CLOSE-COUPLED CANARD WING MODEL AT Unclas 1/02 23802 SUBSONIC SPEEDS (NASA) 86 pHC $.7,5 EFFECT OF WING PLANFORM AND CANARD LOCATION AND GEOMETRY ON THE LONGITUDINAL AERODYNAMIC CHARACTERISTICS OF A CLOSE-COUPLED CANARD WING MO[ AT SUBSONIC SPEEDS Blair B. Gloss C; .LT Langley Research Center 0T, Hampton, Va. 23665 16 .191 NATIONAL AERONAUTICS AND SPACE ADMINISTRATION * WASHINGTON,-D. * JUNE 1975 1. Report No. 2. Government Accession No. 3. Recipient's Catalog No. NASA TN D-7910 4. Title and Subtitle 5. Report Date EFFECT OF WING PLANFORM AND CANARD LOCATION June 1975 AND GEOMETRY ON THE LONGITUDINAL AERODYNAMIC CHARACTERISTICS OF A CLOSE-COUPLED CANARD WING MODEL AT SUBSONIC SPEEDS 7. Author(s) 8. Performing Organization Report No. L-9987 Blair B. Gloss 10. Work Unit No. 9. Performing Organization Name and Address 505-11-21-02 NASA Langley Research Center 11. Contract or Grant No. Hampton, Va. 23665 13. Type of Report and Period Covered 12. Sponsoring Agency Name and Address Technical Note National Aeronautics and Space Administration 14. Sponsoring Agency Code Washington, D.C. 20546 15. Supplementary Notes 16. Abstract A generalized wind-tunnel model with canard and wing planforms typical of highly maneu- verable aircraft was tested in the Langley 7- by 10-foot high-speed tunnel at a Mach number of 0.30 to determine the effect of canard location, canard size, wing sweep, and canard strake on canard-wing interference to high angles of attack. The major results of this investigation may be summarized as follows: the high-canard configuration (excluding the canard strake and canard flap), for both the 600 and 440 swept leading-edge wings, produced the highest maximum lift coefficient and the most linear pitching-moment curves; substantially larger gains in the canard lift and total lift were obtained by adding a strake to the canard located below the wing chord plane rather than by adding a strake to the canard located above the wing chord plane. The 440 swept wing in the presence of the large canard attains significantly higher maxi- mum lift coefficients than the same wing in the presence of the smaller canard with the trailing- edge flap undeflected. There is no effect of wing camber and twist on the canard lift character- istics for the canard located above the wing chord plane. The increase in lift obtained at an angle of attack of 00 by increasing the design lift coefficient of the wing is generally maintained throughout the angle-of-attack range of -4 to 440 for the wing in the presence of the high canard. The addition of the canard strake did not discernibly improve the effect of the canard trailing- edge flap on the canard lift. The data show that, with the exception of the low-canard wing I configuration, greater gains in maximum lift coefficient are obtained by adding the canard and strake than would be antici- pated by adding the equivalent area to the wing-body configuration. In the angle-of-attack range before stall occurs for the wing-alone configuration, the canard downwash has a greater unfavor- able effect on the 600 swept wing than on the 440 swept wing. The experimental- and theoretical- lift data indicate that there are substantial amounts of side-edge vortex lift produced on the 440 swept wing in the presence of the canard located above or in the wing chord plane. 17. Key Words (Suggested by Author(s)) 18. Distribution Statement Canard wing Unclassified - Unlimited Variable camber Canard strakes New Subject Category 02 19. Security Classif. (of this report) 20. Security Classif. (of this page) 21. No. of Pages 22. Price* Unclassified Unclassified 84 $4.75 For sale by the National Technical Information Service, Springfield, Virginia 22151 EFFECT OF WING PLANFORM AND CANARD LOCATION AND GEOMETRY ON THE LONGITUDINAL AERODYNAMIC CHARACTERISTICS OF A CLOSE-COUPLED CANARD WING MODEL AT SUBSONIC SPEEDS Blair B. Gloss Langley Research Center SUMMARY A generalized wind-tunnel model with canard and wing planforms typical of highly maneuverable, aircraft was tested in the Langley 7- by 10-foot high-speed tunnel at a Mach number of 0.30 to determine the effect of canard location, canard size, wing sweep, and canard strake on canard-wing interference to high angles of attack. T1e major results of this investigation may be summarized as follows: the high-canard configuration (exclud- ing the canard strake and canard flap), for both the 600 and 440 swept leading-edge wings, produced the highest maximum lift.coefficient and the most linear pitching-moment curves; substantially larger gains in the canard lift and total lift were obtained by adding a strake to the canard located below the wing chord plane rather than by adding a strake to the canard located above the wing chord plane. The 440 swept wing in the presence of the large canard attains significantly higher maximum lift coefficients than the same wing in the presence of the smaller canard with the trailing-edge flap undeflected. There is no effect of wing camber and twist on the canard lift characteristics for the canard located above the wing chord plane. The increase in lift obtained at an angle of attack of 00 by increasing the design lift coefficient of the wing is generally maintained throughout the angle -of-attack range of -40 to 440 for the wing in the presence of the high canard. The addition of the canard strake did not dis- cernibly improve the effect of the canard trailing-edge flap on the canard lift. The data show that, with the exception of the low-canard wing I configuration, greater gains in maximum lift coefficient are obtained by adding the canard and strake than would be anticipated by adding the equivalent area to the wing-body configuration. In the angle- of-attack range before stall occurs for the wing-alone configuration, the canard downwash has a greater unfavorable effect on the 600 swept wing than on the 440 swept wing. The experimental- and theoretical-lift data indicate that there are substantial amounts of side- located edge vortex lift produced on the 440 swept wing in the presence of the canard above or in the wing chord plane. INTRODUCTION In the studies presented in references 1 to 10, it was shown that the close-coupled canard-wing configuration can provide performance improvements to a maneuvering air- craft. It was also indicated that the aerodynamic characteristics at high angles of attack are very sensitive to configuration variables. Thus, a knowledge of the aerodynamic interaction of the canard and wing is of significant interest. In view of this interest, the National Aeronautics and Space Administration is conducting a study on canard-wing interference to high angles of attack. A generalized wind-tunnel model incorporating two balances to allow separation of the canard contribution from the total forces and moments is being used in the study. The present investigation was conducted in the Langley high-speed 7- by 10-foot tun- nel to determine the effect of canard location, canard size, wing sweep, and canard strake on canard-wing lift interference to high angles of attack. The tests were made at a Mach number of 0.30 for a Reynolds number of 1.56 x 106 based on a mean geometric chord of 23.32 cm (9.18 in.) at angles of attack from approximately -4o to 440 at 00 sideslip. SYMBOLS The International System of Units (SI), with the U.S. Customary Units presented in parentheses, is used for the physical quantities in this paper. Measurements and calcula- tions were made in U.S. Customary Units. The longitudinal data presented in this report are referred to the stability-axis system with the exception of axial force and normal force which are referred to the body-axis system. The moment reference point was taken to be at fuselage station 59.16 cm (23.29 in.) for both balances. A aspect ratio, b 2 /Sw b wing span, 50.8 cm (20.0 in.) CD drag coefficient, Drag qooSw CL lift coefficient, Lift qoSw CL,C lift coefficient obtained from canard balance CL,d wing design lift coefficient CL,M lift coefficient obtained from main balance 2 Pitching moment Cm pitching-moment coefficient, c local chord, cm (in.) " wing mean geometric chord, 23.32 cm (9.18 in.) Ec canard mean geometric chord, cm (in.) 2 q, free-stream dynamic pressure, Pa (lb/ft ) 2 2 Sc exposed canard area, cm (in ) to plane of w reference area of wing with leading and trailing edges extended symmetry, 1032.7 cm 2 (160.0 in 2 ) x longitudinal distance measured from wing leading edge (positive aft), cm (in.) y lateral distance measured from body center line (positive right side of model), cm (in.) z vertical distance from wing chord plane to canard chord plane (positive up), cm (in.) z vertical distance from wing chord plane to point on wing lower surface (positive down), cm (in.) zu vertical distance from wing chord plane to point on wing upper surface (positive up), cm (in.) a angle of attack, deg 6 canard trailing-edge flap deflection (positive trailing edge down), deg Ac canard leading-edge sweep angle, deg At vertical-tail leading-edge sweep angle, deg Aw wing leading-edge sweep angle, deg 3 Subscripts: p potential vie leading-edge vortex lift vse side-edge vortex lift MODEL DESCRIPTION A three-view drawing of the general research model is presented in figure 1.
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