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프링-크래핑 날개의 첫 번째 사이클 운동에 관한 수치적 흐름 가시화

Numerical Flow Visualization of 1st Cycle Motion of a Fling-clapping Wing

  • 손명환 (공군사관학교 항공우주공학과) ;
  • 장조원 (한국항공대학교 항공운항학과)
  • 발행 : 2004.09.01

초록

나비가 비행할 때 적용할 수 있는 프링-크래핑 (fling-clapping) 날개의 첫 번째 사이클 운동에 관한 흐름 가시화가 수행되었다. 본 수치적 흐름 가시화 연구에서는 프링-크랩-정지 (fling-clapping-pause), 크랩-프링-정지(clap-fling-pause)의 단계를 거치는 두 가지 형태의 날개 운동 해석을 위해 시간의존 Navier-Stokes 방정식을 이용하였다. 결과에서는 두개군의 분리와류 쌍과 그것들이 전개되는 과정과 같은 주요 흐름특성이 관찰되었다. 프링-크랩-정지 운동의 경우, 날개가 열리는 프링단계에서 시계반대방향의 강한 분리와류 쌍이 날개 사이의 열린 내부공간에 발달된다. 이어지는 크랩단계에서 분리와류 쌍은 열린 내부공간 밖으로 이동된다. 크랩-프링-정지 운동의 경우, 크랩 단계의 외부 공간에서 발달한 분리와 류 쌍은 뒤따르는 프링 단계에서 열린 내부공간내로 움직인다. 크랩-프링-정지 운동의 프 링 단계에서 발생된 열린 내부공간의 분리와류 쌍은 프링-크랩-정지 운동의 프링단계에서 발생된 열린 내부공간의 분리와류 짱보다 더 강한 와류 쌍임이 관찰되었다.

A flow visualization of the 1st cycle motion of a fling-clapping wing that might be employed by butterflies during flight is performed. In this numerical flow visualization, he time-dependent Navier-Stokes equations are solved for two wing motion types; 'fling followed by clap and pause' and 'clap followed by fling and pause'. The result is observed regarding the main flow features such as the sequential development of the two families of separation vortex pairs and their movement. For the fling followed by clap and pause motion, a strong separation vortex pair of counter-clockwise develops in the opening between the wings in the fling phase and they then move out from the opening in the following clap phase. For the clap followed by fling and pause motion, the separation vortex pair developed in the outside space in the clap phase move into the opening in the following fling phase. The separation vortex pair in the opening developed in the fling phase of the clap followed by fling and pause motion is observed to be stronger than that in the opening developed in the fling phase of the fling followed by clap and pause motion.

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참고문헌

  1. Weis-Fogh, T., "Quick estimates of flight fitness in hovering animals including novel mechanisms for lift production," The Journal of Experimental Biology, Vol. 59, 1973, pp . 169-230.
  2. Lighthill, M. J., "On the Weis-Fogh mechanism of lift generation," Vol. 60, 1973, pp.1-17. https://doi.org/10.1017/S0022112073000017
  3. Maxworthy, T., "Experiments on the Weis-Fogh mechanism of lift generation by insects in hovering flight. Part 1. Dynamics of the 'fling'," Journal of Fluid Mech., Vol. 93, 1979, pp . 47-63. https://doi.org/10.1017/S0022112079001774
  4. Sohn, M. H., and Wu, J. C. "A Numerical Study of the Weis-Fogh Mechanism," AlAA Paper No. 87-0238, 1987.
  5. Maxworthy, T., "The Fluid dynamics of Insect Flight," Annual Review of Fluid Mechanics, Vol. 13, 1981, pp . 329-350. https://doi.org/10.1146/annurev.fl.13.010181.001553
  6. Brackenbury, J. H., "Kinematics of take-off and Climbing Flight in Butterflies," J. Zool.,Lond. 224, 1991, pp . 251-274. https://doi.org/10.1111/j.1469-7998.1991.tb04803.x
  7. Wootton, R J., "Leading Edge Section and Asymmetric Twisting in the Wing of Flying Butterflies (Insecta, Papilionoidea) ." The Journal of Experimental Biology, Vol. 180, 1993, pp .105-117.
  8. Dudley, R, "Biomechanics of Flight in Neotropical Butterflies: Morphometries and Kinematics," The Journal of ExperimentalBiology, Vol. 150, 1990, pp. 37-53.
  9. Ellinton, C. P., "The Novel Aerodynamics of Insect Flight: Application to Micro-Air Vehicles," The Journal of Experimental Biology,Vol. 202, 1999, pp . 3439-3448.
  10. 장조원, 손명환, "Fling-clapping운동을 하는 대칭평판날개의 비정상흐름연구." 한국항공우주학회지, 제23권 제3호, pp. 25-32.
  11. Wu, J. H. , Sun, M., "Unsteady Aerodynamic forces of a flapping wing," Journal of Experimental Biology, Vol. 207, No.7, 2004, pp. 1137-1150. https://doi.org/10.1242/jeb.00868
  12. Sane, S. P., "The Aerodynamics of Insect Flight," The Journal of Experimental Biology,Vol. 206, No. 17, 2003, pp. 4191-4208. https://doi.org/10.1242/jeb.00663
  13. Ramarnurti, R , and Sandberg, W.,"Simulation of Flow about Flapping Airfoils Using Finite Element Incompressible Flow Solver," AIAA Journal, Vol. 39, No. 2, 2001,pp . 253-260. https://doi.org/10.2514/2.1320
  14. Wu, J. C, "Fundamental Solutions and Numerical Methods for Flow Problems," International Journal for Numerical Methods in Fluids, Vol. 4, 1984, pp. 185-201. https://doi.org/10.1002/fld.1650040207
  15. 손명환, "Weis-Fogh Wing의 Partial Fling-clap운동과 관련한 비정상 공기역학," 한국항공우주학회지, 제25권 제1호, 1997, pp.14-24.