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Low Speed Thrust Characteristics of a Modified Sonic Arc Airfoil Rotor through Spin Test Measurement

  • Lee, Jang-Chang (Department of Mechanical Engineering, Andong National University)
  • Received : 2012.07.30
  • Accepted : 2012.09.26
  • Published : 2012.09.30

Abstract

The low speed aerodynamic characteristics for a modified sonic arc airfoil which is designed by using the nose shape function of sonic arc, the shape function of NACA four-digit wing sections, and Maple are experimentally investigated. The small rotor blades of a modified sonic arc and NACA0012 airfoil are precisely fabricated with a commercially available light aluminum(Al 6061-T6) and are spin tested over a low speed range (3000rpm-5000rpm). In a consuming power comparison, the consuming powers of NACA0012 are higher than that of modified sonic arcs at each pitch angle. The measured rotor thrust for each pitch angle is used to estimate the rotor thrust coefficient according to momentum theory in the hover state. The value of thrust coefficients for both two airfoils at each pitch angle show almost constant values over the low Mach number range. However, the rotor thrust coefficient of NACA0012 is higher than that of the modified sonic arc at each pitch angle. In conclusion, the aerodynamic performance of NACA0012 is better than that of modified sonic arcs in the low speed regime. This test model will provide a convenient platform for improving the aerodynamic performance of small scale airfoils and for performing design optimization studies.

Keywords

References

  1. Nixon, D., Unsteady Transonic Aerodynamics, Progress in Astronautics and Aeronautics, AIAA, Washington DC, USA,1988.
  2. Cole, J. D. and Cook, L. P., Transonic Aerodynamics, North-Holland, New York, USA, 1986.
  3. Whitcomb, R. T. and Clark, L. R., "An Airfoil Shape for Efficient Flight at Supercritical Mach Numbers", NASA TM X-1109, 1965.
  4. Spaid, F. W., Dahlin, J. A., Roos, F. W., and Stivers, L. S., Jr., "An Experimental Study of Transonic Flow about a Supercritical Airfoil. Static Pressure and Drag data Obtained from Tests of a Supercritical Airfoil and an NACA0012 Airfoil at Transonic Speeds, Supplement", NASA-TM-81336- SUPPL, 1983.
  5. Harris, D. C., McGhee, R. J., and Allison, D. O., "Low- Speed Aerodynamic Characteristics of a 14-percent-Thick NASA Phase 2 Supercritical Airfoil Designed for a Lift Coefficient of 0.7", NASA TM 81912, 1980.
  6. McGhee R. T., Beasley W.D., and Whitcomb R. T., "NASA Low- and Medium-Speed Airfoil Development", NASA Technical Memorandum 78709, 1979.
  7. Kim, J.M., Rusak. Z., and Koratkar, N., "Small-Scale Airfoil Aerodynamic Efficiency Improvement by Surface Temperature and Heat Transfer", AIAA Journal, Vol.41, No.11, 2003, pp. 2105-2113. https://doi.org/10.2514/2.6829
  8. Lee, J.C., "Aerodynamic performance of Modified Sonic Arc Airfoil", Journal of Korean Society for Aeronautical and Space Sciences, Vol. 35, No. 7, 2007, pp. 581-585. https://doi.org/10.5139/JKSAS.2007.35.7.581
  9. Lee, J.C., "Low Speed Aerodynamic Characteristic of Modified Sonic Arc Airfoil", Journal of Korean Society for Aeronautical and Space Sciences, Vol.40, No.2, 2012, pp. 139- 145. https://doi.org/10.5139/JKSAS.2012.40.2.139
  10. Rusak, Z., "Transonic Flow around Optimum Critical Airfoils", SIAM Journal of Applied Mathematics, Vol.55, No.5, 1995, pp.1455-1467. https://doi.org/10.1137/S0036139993274210
  11. Schwendenman, D. W., Kropinski, M.C.A., and Cole, J.D., "On the Construction and Calculation of Optimal Nonlifiting Critical Airfoils", ZAMP Journal of Applied Mathematics and Physics, Vol. 44, 1993, pp. 556-571. https://doi.org/10.1007/BF00953667
  12. Abbott, I.H. and von Doenhoff, A.E., Theory of Wing Sections, Dover Publications Inc., New York, 1959.
  13. Leishman, J.G., Principles of Helicopter Aerodynamics, Cambridge Univ. Press, Cambridge, UK, 2000.