DOI QR코드

DOI QR Code

A Study on Nozzle Performance Influence with Aft-deck Geometry

Aft-deck 형상에 의한 노즐 성능 영향성 연구

  • Received : 2020.12.14
  • Accepted : 2021.03.28
  • Published : 2021.04.30

Abstract

The Aft-deck is being applied to the latest unmanned aircraft for the purpose of shielding the gas turbine exhaust plume or spreading jets to increase the mixing rate with the ambient air, thereby reducing the temperature of exhaust gases. In this study, we would like to find out how the performance of the nozzle is affected by the design variables of the Aft-deck. The design variables of aft-deck are selected as length, expansion angle and upper deck shape. The correlation between thrust and plume shielding rate with the length variable is presented. And the correlation between the thrust and the jet diffusion range is presented according to the expansion angle. In addition, the thrust increase effect is confirmed by the removal of the upper deck and the characteristics of transverse velocity vector determined mixing performance with external flow.

Aft-deck은 가스터빈 배기 플룸을 차폐하거나, 제트를 확산하여 외부 공기와 혼합율을 증가시켜 배기가스의 온도를 저감하기 위한 용도로 최신 무인항공기에 적용되고 있다. 본 연구에서는 Aft-deck의 설계 변수에 따라 노즐의 성능이 어떻게 영향을 받는지 알아보고자 하였다. Aft-deck의 설계 변수로는 길이, 확산각, 상부 덱 형상으로 선정하였으며, 길이 변수에 따른 추력과 차폐율 간의 상관관계를 제시하였다. 그리고 확산 각도의 범위에 따라 노즐 추력과 제트 확산에 대한 상관관계를 제시하였다. 또한, 상부 덱 제거를 통해 추력 향상 효과를 확인하였으며, 횡 방향 속도 벡터의 특성이 외부 유동과의 혼합 성능을 결정하는 것을 알게 되었다.

Keywords

Acknowledgement

이 논문은 국방과학연구소가 지원하는 저피탐무인항공기 추진계통 IR 감소 기술 연구로 수행되었습니다.

References

  1. L. Bougas., M. Hornung, "Propulsion system intergration and thrust vectoring aspect for scaled jet UAVs, CEAS Aeronaut. Journal, Vol. 4 pp. 327-343, 2013. https://doi.org/10.1007/s13272-013-0076-x
  2. W.M. Presz. G. Reynolds. D.C. McCormick, "Thrust augment using mixer-ejectordiffuser systems," AIAA, 40th AIAA Sciences Meeting & Exhibit, Reno, NV, pp. 94-0020, January 2002.
  3. Brian J. Tester and Michael J. Fisher, "A contribution to the understanding and prediction of jet noise generation in forced mixer," 12th AIAA/CEAS Aeroacoustics Conference, Cambridge Massachusetts, pp. 2006-2542, May 2006.
  4. Pelt HV, Neely A, Young J., "A system study on fluidic thrust vectoring," 20th AIAA International Space Planes and Hypersonic Systems and Technologies Conferences, Glasgow, Scotland, AIAA paper 2015-3565, July 06-09, 2015.
  5. Cen Z., Smith T., Stewart P., Steart J, "Intergrated flight/thrust vectroing control for jet-powerd unmanned aerial vehicles with ACHEON propulsion," Journal of Aerospace Engineering, Vol. 229, No. 5, pp. 1057-75, 2015.
  6. B.L. Berrier., M.L. Mason, "Static performance of an axisymmetric nozzle with post-exit vanes for multi axis thrust vectoring, in: NASA TP-2800, 1988.
  7. D.J Wing., C.T.L., Mills., M.L. Mason, "Static investigation of a multi axis thrust vectoring nozzle with variable internal contouring ability," NASA TP-3628, 1997.
  8. K.A.Deere., B.L. Berrier., J.D. Flamm., S.K. Johnson, "Computational study of fluidic thrust vectoring using separation control in a nozzle," The 21st AIAA Applied Aerodynamics Conference, pp. 3803, 2003.
  9. Farzad Forghany, Mohammad Taeibe Rahni and Abdollah Asdollahi Ghohieh, "Numerical investigation of freestream flow effects on thrust vector control performance," Ain Shams Engineering Journal, Vol. 9, pp. 3293-3303, 2018. https://doi.org/10.1016/j.asej.2017.12.004
  10. T.Chandra Sekar., A.Kushari., B.Mody., B.Uthup, "Fluidic thrust vectoring using transverse jet injection in a convergin nozzle with Aft-deck," Experimental Thermal and Fluid Science, Vol. 86, pp. 189-203, 2017. https://doi.org/10.1016/j.expthermflusci.2017.04.017
  11. P.Behrouzi and J.J. McGuirk., "Underexpanded jet development from a rectangular nozzle with Aft-deck," AIAA Journal, Vol. 53, No. 5, pp. 1287-1298, 2015. https://doi.org/10.2514/1.J053376
  12. Miau. J.J., Leu, T.S., Chou, J.H., and Lin, S. A., "Flow Distortion a Circular-to-Rectangular Transition Duct," AIAA Journal, Vol. 28, No. 8, 1990, pp. 1447-1456. https://doi.org/10.2514/3.25237
  13. Hyun-Jin Lee, Ji-Hyun Lee, Rho-Shin Myong, Sun-Mi Kim, Sung-Man Choi, Won-Cheol Kim., "Computational and Experimental Investigation of Thermal Flow Field of Micro Turbojet Engine with Various Nozzle Configurations," The Korean Society for Aeronautical & Space Sciences, Vol. 46, No. 2, 2018, pp. 150-158. https://doi.org/10.5139/JKSAS.2018.46.2.150
  14. Hyun-Jin Lee, Ji-Hyun Lee, Rho-Shin Myong, Sun-Mi Kim, Sung-Man Choi, Won-Cheol Kim, "Computational and Experimental Investigation of Thermal Flow Field of Micro Turbojet Engine with Various Nozzle Configurations," The Korean Society for Aeronautical & Space Sciences, Vol. 46, No. 2, 2018, pp. 150-158. https://doi.org/10.5139/JKSAS.2018.46.2.150
  15. Meng Sing Liou, "A sequel to AUSM, Part II: AUSM+-up for all speeds," Journal of Computational Physics, Vol. 129, Issue. 2, pp 364-382, 1996. https://doi.org/10.1006/jcph.1996.0256
  16. Sun, X.-L., Wang, Z.-X., Zhou, L., Shi, J.-W., and Liu, Z.-W., "Influences of Design Parameters on a Double Serpentine Convergent Nozzle," Journal of Engineering for Gas Turbines and Power, Vol. 138, No. 7, pp. 072301-072316, 2016. https://doi.org/10.1115/1.4032338
  17. C.-M. HO, E, Gutmark, "Vortex induction and mass entrainment in a small aspect ratio elliptic jet," J. Fluid Mech. 1987.