한국항공우주학회지 (Journal of the Korean Society for Aeronautical & Space Sciences)

  • 제46권2호
  • /
  • Pages.95-105
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  • 2018
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  • 1225-1348(pISSN)
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  • 2287-6871(eISSN)
한국항공우주학회 (The Korean Society for Aeronautical and Space Sciences)
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다중 덕트 팬 전진 비행 특성에 대한 수치적 연구

Numerical Investigation of Forward Flight Characteristics of Multi-Ducted Fan

  • Roh, Nahyeon (Department of Aerospace Engineering, Pusan National University) ;
  • Oh, Sejong (Department of Aerospace Engineering, Pusan National University) ;
  • Park, Donghun (Department of Aerospace Engineering, Pusan National University)
  • 투고 : 2017.09.12
  • 심사 : 2018.01.30
  • 발행 : 2018.02.01
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초록

차세대 회전익기 개발에서 고속화는 중요한 과제이며, 선행 연구들을 통해 덕트 팬을 가지는 비행체는 고속화 실현 가능성이 높은 형상으로 평가된다. 본 연구에서는 다중 덕트 팬 비행체의 전진 비행시의 유동 특성 및 공력 성능 분석을 위한 전산해석을 수행하였다. 전방 팬의 공력 성능은 자유류 유동과 팬 유입류에 의해 결정되는 반면, 후방 팬의 성능은 전방 팬에서 발생한 유동에 지배적인 영향을 받음을 확인하였다. 전진 속도가 증가하며 전방 팬 입구에서의 유동 박리는 후방 팬보다 먼저 발생하며, 덕트 입구 박리는 팬 추력의 증가를 유도한다. 두 덕트 팬 간의 상호 작용으로 인해 후방 팬에는 상대적으로 정렬된 유동이 유입되므로 박리 이전까지 추력이 꾸준히 감소하고, 전/후방 팬의 추력의 급격한 변화는 동시에 발생한다. 전진 속도에 따라 전체 비행체의 수직력은 감소하였다. 이는 팬 후류에 의한 동체 아랫면 압력 저하가 주요 원인으로 분석되었다.

Increasing cruise speed is an important issue for the development of the next generation rotorcraft. Among several concepts proposed by previous research, the rotorcraft with ducted fan demonstrates its possibility of high-speed flight. In this study, numerical simulations are conducted to investigate the aerodynamic and flow characteristics of multi-ducted fan in forward flight. The aerodynamic efficiency around front ducted fan is determined by interaction between free-stream velocity and the induced velocity. While flow characteristics of rear ducted fan are dominantly influenced by the front ducted fan. Separation in the front ducted fan occurs faster than that of rear ducted fan, and the separation at duct inlet induces an increase of fan thrust. As a result of interaction effect between each ducted fan, relatively aligned inflow enters to the rear ducted fan. Therefore, thrust of the rear fan is decreased steadily before separation, and sudden changes of thrust in fans occur simultaneously. Due to the pressure decrease on lower surface, the normal force of rotorcraft is reduced with forward speed.

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참고문헌

  1. Hwang, C. J,. Jeong, J. H., Joo, J., and Hwang, I. H., "Noise Reduction Technology for Rotorcraft," Journal of Korean Society for Noise and Vibration Engineering, Vol. 17, No. 5, 2007, pp. 8-15.
  2. Hwang, C. J., and Kim, S. B., "Analysis and Trend Curve Derivation of Major Design Parameters of Unmanned and Manned Rotorcrafts," Journal of The Korean Society for Aeronautical and Space Sciences, Vol. 34, No. 2, 2006, pp. 26-35. https://doi.org/10.5139/JKSAS.2006.34.2.026
  3. Park, J. W., Hwang, C. J., Kim, J. H., Ahn, I. K., and Lee, J. H., "Status and Challenges of a High Speed Rotorcraft Technology Development," Current Industrial and Technological Trends in Aerospace, Vol. 10, No. 1, 2012, pp. 41-48.
  4. Hirschberg, M., "Sikorsky X2 Goes Faster and Faster," Vertiflite, Vol. 56, No. 3, 2010.
  5. Hirschberg, M., "X2, X3, S-97 and X-49 :The Battle of the Compounds is Joined," Vertiflite, Vol. 56, No. 4, 2010.
  6. "Russia Eyes High Speed Helicopters," Flight International, 2011.
  7. Kim, J. M., "KARI Experience of the Compound Rotorcraft Concept Study and Recent Trend of High-speed VTOL Development in the World," Proceeding of The Korean Society for Aeronautical and Space Sciences Fall Conference, November 2015, pp. 866-870.
  8. Gregory, Nigel, W. G. Raymer. and Edna M. Love., The effect of forward speed on the inlet flow distribution and performance of a lifting fan installed in a wing, HM Stationery Office, 1965.
  9. Kuhn. R. E., and Marion O. M. K. Jr,, "NASA research on the aerodynamics of jet VTOL engine installations," National Aeronautics and Space Administration, 1965.
  10. Gregory, Nigel, W. G. Raymer., and Edna M. L., Wind Tunnel Tests of a Wing Fitted with a Single Lifting Fan, HM Stationery Office, 1967.
  11. Schaub, U. W., "Experimental investigation of flow distortion in fan-in-wing inlets," Journal of Aircraft, Vol 5, No. 5, 1968, pp. 473-478. https://doi.org/10.2514/3.43969
  12. Grahame, W. E., "The aerodynamic effects of lift jet and lift fan inlets in transition flight," American Institute of Aeronautics and Astronautics, Vol. 6, No. 2, 1968, pp. 150-155. https://doi.org/10.2514/3.4455
  13. S., N. O., and S. Lieblein., "Theoretical analysis of flow in VTOL lift fan inlets without crossflow," National Aeronautics and Space Administration, NASA-TN-D5065, 1969.
  14. Wu, J. Chen-yuan,, H. M. McMahon., and J. E. Hubbartt., "Potential flow studies of lift-fan inflow interference phenomena," Georgia Institute of Technology, 1971.
  15. Panaras, G., et al., "Theoretical and experimental investigation of the performance of a desiccant air-conditioning system." Renewable Energy, Vol 35, No.7, 2010, pp. 1368-1375. https://doi.org/10.1016/j.renene.2009.11.011
  16. Thouault, N., Breitsamter, C., and Adams, N. A., "Numerical and experimental analysis of a generic fan-in-wing configuration," Journal of Aircraft, Vol. 46, No. 2, 2009, p. 656. https://doi.org/10.2514/1.39750
  17. Thouault, N., Breitsamter, C., and Adams, N., "Numerical investigation of inlet distortion on a wing-embedded lift fan," Journal of Propulsion and Power, Vol. 27, No. 1, 2011, pp. 16-28. https://doi.org/10.2514/1.46046
  18. www.openfoam.com
  19. LEISHMAN, Gordon J. Principles of helicopter aerodynamics with CD extra, Cambridge university press, 2006.
  20. Kim, T. W., Oh, S. J., and Yee, K. J., "The Extension and Validation of OpenFOAM Algorithm for Rotor Inflow Analysis using Actuator Disk Model," Journal of The Korean Society for Aeronautical and Space Sciences, Vol. 39, No. 12, 2011, pp. 1087-1096. https://doi.org/10.5139/JKSAS.2011.39.12.1087
  21. Rethore, P. E. M., and Sorensen, N. N., "Actuator disc model using a modified Rhie-Chow/SIMPLE pressure correction algorithm. Comparison with analytical solutions," Proceeding of European Wind Energy Conference and Exhibition, January 2008.
  22. www.eurocopter.com
  23. Woo, C. H., Park, N. E., Lee, S. G., and Lee, S. B., "Research on Aerodynamic Characteristics about Fan-in-Fin type Tail Rotor System Using the CFD Analysis," Proceeding of The Korean Society for Aeronautical and Space Sciences Fall Conference, November 2016, pp. 561-562.
  24. Jang, J. S., Ryi, J. H., Hyun, Y. O., Yim, J. B., and Choi, J. S., "A Comparison of Aerodynamic Performance between an Isolated Fan and a Ducted Fan," Proceeding of The Korean Society for Aeronautical and Space Sciences Fall Conference, April 2017, pp. 431-432.