Improvement of Cooling Effects of Pylon Injector for Scramjet Combustor

스크램제트 연소기용 파일런 분사기 냉각성능 개선 연구

  • 이상현 (울산대학교 항공우주공학과)
  • Received : 2010.12.06
  • Accepted : 2011.09.16
  • Published : 2011.10.30

Abstract

A new film cooling method to protect the pylon injector from aerodynamic heating for a scramjet combustor is proposed and verified with numerical methods. The conditions for the Mach 8 flight at an altitude of 35km are considered. Air is considered as a coolant. Three-dimensional Navier-Stokes equations with $k-{\omega}$ SST turbulence model are used. A downward injection of coolant from the top of the pylon gives higher cooling effects with less mass flow rate of coolant than the upward coolant injection from bottom of the pylon. Also, the downward injection shows little flow separation due to the favorable pressure gradient and does not disturb the flowfields near pylon injector, which results in reduction of pressure losses.

스크램제트 연소기용 파일런 분사기를 공력가열로부터 보호하기 위한 새로운 냉각 방법을 제안하고, 이를 수치적으로 검증하였다. 비행 마하수가 8인 경우를 고려하였으며, 공기를 냉각 유체로 고려하였다. 수치연구를 위하여 3차원 Navier-Stokes 방정식과$k-{\omega}$ SST 난류 모델을 이용하였다. 냉각류를 파일런 위쪽에서 하향 분사하는 방법은, 냉각류를 파일런 바닥 쪽에서 상향 분사하는 방법에 비해 적은 유량으로 더 나은 냉각효과를 나타내었다. 또한, 순압력 구배 상황에서 냉각류를 분사함으로써 분사유동의 박리가 줄어들고 파일런 분사기 앞쪽에 유동장 교란이 줄어들어, 압력손실 저감 효과가 있음을 확인하였다.

Keywords

References

  1. Bogdanoff, D. W., "Advanced Injection and Mixing Techniques for Scramjet Combustors," Journal of Propulsion and Power, Vol. 10, No. 2, 1994, pp.183-190 https://doi.org/10.2514/3.23728
  2. Lee, S-H, and Mitani, T., "Mixing Augmentation of Transverse Injection in Scramjet Combustor," Journal of Propulsion and Power, Vol. 19, No. 1, Jan. 2003, pp.115-124 https://doi.org/10.2514/2.6087
  3. Gruber, M. R., Nejad, A. S., and Goss, L. P., "Surface Pressure Measurements in Supersonic Transverse Injection Flowfield," AIAA 97-3254, 1997
  4. Schetz, J. A., Weinraub, R. A., and Mahaffey, R. E., Jr., "Supersonic Transverse Injection into a Supersonic Stream," AIAA Journal, Vol. 6, No. 5, 1968, pp.933-934 https://doi.org/10.2514/3.4631
  5. Gruber, M. R., Nejad, A. S. Chen, T. H. and Dutton, J. C. " Bow Shock/Jet Interaction in Compressible Transverse Injection Flowfields," Phys. Fluids, Vol. 9, No. 5, 1997, pp.1448-1461 https://doi.org/10.1063/1.869257
  6. 김경무, 백승욱, 김윤곤, "초음속 공기유동으로의 연료분사노즐 종횡비 변화에 대한 연소특성 연구," 한국추진공학회지, 제8권, 제1호, 2004, pp.44-53
  7. Sislian, J. P., and Parent, B., "Hypervelocity Fuel/Air Mixing in a Shcramjet Inlet," Journal of Propulsion and Power, Vol. 20, No. 2, 2004, pp.263-272 https://doi.org/10.2514/1.9252
  8. Sislian, J. P. Martens, R. P., Schwartzentruber, T. E., and Parent, B., "Numerical Simulation of a Real Shcramjet Flowfield," Journal of Propulsion and Power, Vol. 22, No. 5, 2006, pp.1039-1048 https://doi.org/10.2514/1.14895
  9. Alexander, D. C., Sislian, J. P., and Parent, B., "Hypervelocity Fuel/Air Mixing in Mixed-Compression Inlets of Scramjets," AIAA Journal, Vol. 44, No. 10, 2006, pp.2145-2155 https://doi.org/10.2514/1.12630
  10. Gruber, M. R., Carter, C. D., Montes, D. R., Haubelt, L. C., and King, P. I., Hsu, K-Y., "Experimental Studies of Pylon-Aided Fuel Injection into a supersonic Crossflow," Journal of Propulsion and Power, Vol. 24, No. 3, 2008, pp.460-470 https://doi.org/10.2514/1.32231
  11. Doster, J. C., King, P. I., Gruber, M. R., Carter, C. D., and Hsu, K-Y., "In-Stream Hypermixer Fueling Pylons in Supersonic Flow," Journal of Propulsion and Power, Vol. 25, No. 4, 2009, pp.885-901 https://doi.org/10.2514/1.40179
  12. 이상현, "냉각 파일런 분사를 이용한 스크램제트 연소기 내 혼합증대," 한국추진공학회지, 제14권, 제1호, 2010, pp.20-28
  13. Menter, F. R., "Two-equation Eddy-viscosity Turbulence Models for Engineering Applications," AIAA Journal, Vol. 32, No. 8, 1994, pp.1598-1605 https://doi.org/10.2514/3.12149
  14. Reid, C. R., Prausnitz, J. M., and Poling, B. E., The properties of Gases and Liquids, 4th ed., McGraw-Hill, New York, 1988
  15. Edwards, J. R., Liou, M-S., "Low-Diffusion Flux-Spiliting Methods for at All Speeds," AIAA Journal, Vol. 36, No. 9, 1998
  16. Yoon, S., and Jameson, A., "Lower-Upper Symmetric-Gauss-Seidel Method for the Euler and Navier-Stokes Equation," AIAA Journal, Vol. 26, No. 9, 1988, pp.1025-1026 https://doi.org/10.2514/3.10007
  17. Lee, S-H., Jeung, I-S. and Yoon, Y., "Computational Investigation of Shock-Enhanced Mixing and Combustion," AIAA Journal, Vol. 35, No. 12, 1997, pp.1813-1820 https://doi.org/10.2514/2.56