DOI QR코드

DOI QR Code

A study on in-flight acoustic load reduction in launch vehicle fairing by FE-SEA hybrid method

FE-SEA 하이브리드 기법을 이용한 비행 중 발사체 페어링 내부 음향하중 저감에 관한 연구

  • Received : 2020.06.19
  • Accepted : 2020.07.18
  • Published : 2020.07.31

Abstract

Launch vehicles are subject to airborne acoustic loads during atmospheric flight and these effects become pronounced especially in transonic region. As the vibration due to the acoustic loads can cause malfunction of payloads, it is essential to predict and reduce the acoustic loads. In this study, a complete process has been developed for predicting airborne vibro-acoustic environment inside the payload pairing and subsequent noise reduction procedure employing acoustic blankets and Helmholtz resonators. Acoustic loads were predicted by Reynolds-Averaged Navier-Stokes (RANS) analysis and a semi-empirical model for pressure fluctuation inside turbulent boundary layer. Coupled vibro-acoustic analysis was performed using VA One SEA's Finite Element Statistical Energy Analysis (FE-SEA) hybrid module and ANSYS APDL. The process has been applied to a hammerhead launch vehicle to evaluate the effect of acoustic load reduction and accordingly to verify the effectiveness of the process. The presently developed process enables to obtain quick analysis result with reasonable accuracy and thus is expected to be useful in the initial design phase of a launch vehicle.

발사체는 비행 중 공기역학적 현상에 기인하는 음향하중의 영향을 받는데, 특별히 천음속 영역에서 그 영향이 증가된다. 음향하중으로 인한 페어링 내부 소음진동은 탑재물의 오작동을 유발할 수 있어 이를 예측하고 저감하는 과정이 필수적이다. 본 연구에서는 발사체 외부에 작용하는 공기역학적 음향하중에 의한 페어링 내부 음향 진동환경을 예측하고, 음향 블랭킷과 헬름홀츠 공명기를 이용하여 소음저감 설계를 구현하는 프로세스를 개발하였다. 음향하중 예측은 Reynolds-Averaged Navier-Stokes(RANS) 유동해석 결과와 난류 경계층 내부 압력섭동에 관한 준 경험식을 이용하였고, 음향진동 연성해석은 ANSYS APDL과 VA One SEA의 Finite Element Statistical Energy Analysis(FE-SEA) 하이브리드 해법을 이용하였다. 개발된 절차를 천음속 해머 헤드형 발사체에 적용하여 음향하중 저감효과를 확인하고 개발된 절차의 유효성을 검증하였다. 본 연구에서 개발된 절차는 타당한 수준의 정확도로 신속한 결과를 얻을 수 있어 발사체 초기설계 단계에 유용하게 쓰일 수 있을 것으로 예상된다.

Keywords

References

  1. C. P. Lubert, "From sputnik to SpaceX(R) - 60 years of rocket launch," J. Acoust. Soc. Am. 14, 38-46 (2018).
  2. J. P. Arenas and R. N. Margasahayam, "Noise and vibration of spacecraft structures," Ingenaire: Revista Chilena de Ingenieria. 14, 251-264 (2006).
  3. J. Houston, D. Counter, J. Kenny, and J. Murphy, "ATK launch vehicle (ALV-X1) liftoff acoustic environments-prediction vs. measurement," 15th AIAA/ CEAS Aeroacoustics Conf. (2009).
  4. G. Rainey, "Progress on the launch-vehicle buffeting problem," J. Spacecr. Rockets. 2, 289-299(1965). https://doi.org/10.2514/3.28174
  5. H. A. Cole, A. L. Erickson, and A. G. Rainey, "Buffeting during atmospheric ascent," NASA Tech. Rep., SP-8001, 1970.
  6. D. J. Piatak, M. K. Sekula, and R. D. Rausch, "Ares launch vehicle transonic buffet testing and analysis techniques," J. Spacecr. Rockets. 49, 798-807(2012). https://doi.org/10.2514/1.A32175
  7. C. F. Coe and J. B. Nute, "Steady and fluctuating pressures at transonic speeds on hammerhead launch vehicles," NASA Tech. Rep., TM X-778, 1962.
  8. C. F. Coe, "The effects of some variations in launchvehicle nose shape on steady and fluctuating pressures at transonic speeds," NASA Tech. Rep., TM X-646, 1962.
  9. R. C. Robinson, P. R. Wilcox, B. J. Gambucci, and R. E. George, "Dynamic response of a family of axisymmetric hammerhead models to unsteady aerodynamic loading," NASA Tech. Rep., TN D-4504, 1968.
  10. S. R. Park, M. S. Kim, H. I. Kim, and S. G. Lee, "A study on prediction of acoustic loads of launch vehicle using NURBS curve modeling" (in Korean), J. of the Korean Society for Aeronautical & Space Sciences 46, 106-113(2018). https://doi.org/10.5139/JKSAS.2018.46.2.106
  11. M. V. Lowson, "Prediction of boundary layer pressure fluctuations," Wyle Lab., Tech. Rep., 1968.
  12. J. E. Robertson, "Prediction of in-flight fluctuating pressure environments including protuberance induced flow," Wyle Lab., Tech. Rep., 1971.
  13. G. M. Corcos, "The structure of the turbulent pressure field in boundary layer flows," J. Fluid. Mech. 18, 353-378(1964). https://doi.org/10.1017/S002211206400026X
  14. B. M. Efimtsov, N. M. Kozlov, S. V. Kravchenko, and A. O. Andersson, "Wall pressure fluctuation spectra at small forward-facing steps," Proc. 5th AIAA/CEAS Aeroacoustics Conf. and Exhibit. AIAA-99-1964 (1999).
  15. T. S. Miller, Turbulent boundary layer models for acoustic analysis, (Ph.D. Dissertation, Wichita State. University, 2011).
  16. K. Ritos, D. Drikakis, and I. W. Kokkinakis, "Wall-pressure spectra models for supersonic and hypersonic turbulent boundary layers," J. Sound and Vibration, 443, 90-108(2019). https://doi.org/10.1016/j.jsv.2018.11.001
  17. J. A. Cockburn and J. E. Robertson, "Vibration response of spacecraft shrouds to in-flight fluctuating pressures," J. Sound and Vibration, 33, 399-425 (1974). https://doi.org/10.1016/S0022-460X(74)80226-9
  18. M. Y. Yang and J. F. Wilby, "Derivation of aero-induced fluctuating pressure environments for Ares IX," Proc. 14th AIAA/CEAS Aeroacoustics Conf. paper no.2801 (2008).
  19. J. Panda, "Aeroacoustics of space vehicles," NASA Advanced Modeling & Simulation Seminar Series, https://www.nas.nasa.gov/publications/ams/2014/04-08-14.html, (Last viewed July 28, 2020).
  20. S. R. Park, M. S. Kim, and S. G. Lee "A study on the acoustic loads prediction of flight vehicle using computational fluid dynamics- empirical hybrid method" (in Korean), J. Acoust. Soc. Kr. 37, 163-173(2018).
  21. D. Bianco, F. P. Adamo, M. Barbarino, P. Vitiello, D. Bartoccini, L. Federico, and R. Citarella, "Integrated aero-vibroacoustics: the design verification process of Vega-C launcher," Applied Sciences, 8, 88 (2018). https://doi.org/10.3390/app8010088
  22. W. O. Hughes and A. M. McNelis, "Acoustic test results of melamine foam with application to payload fairing acoustic attenuation systems," NASA Tech. Rep., TM-2014-218350, 2014.
  23. F. R. Menter, "Two-equation eddy-viscosity turbulence models for engineering applications," AIAA Journal, 32, 1598-1605(1994). https://doi.org/10.2514/3.12149
  24. Y. S. Jang and Y. M. Yi, "Structural design of payload section of KSR-III" (in Korean), Aerospace Engineering and Technology, 1, 117-127(2002).
  25. W. O. Hughes, A. M. McNelis, and H. Himelblau, "Investigation of acoustic fields for the cassini spacecraft: Reverberant versus launch environments," NASA-TM-2000-209387, 2000.