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Simulations of a low-boom, axisymmetric, external compression inlet

Published online by Cambridge University Press:  27 January 2016

T. Coyne
Affiliation:
University of Chicago, Chicago, USA
E. Loth*
Affiliation:
Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, USA
J. Koncsek
Affiliation:
Seattle, USA
D. Davis
Affiliation:
Aerojet (currently at NASA GRC), Cleveland, USA
T. Conners
Affiliation:
Gulfstream Aerospace Corporation, Savannah, Georgia, USA
D. Howe
Affiliation:
Technical Fellow, Gulfstream Aerospace Corporation, Savannah, USA

Abstract

Computational simulations have been used to study a new low-boom, axisymmetric, external compression supersonic inlet with an on-design Mach number of 1·7. The inlet incorporates a relaxed compression surface with a near-zero cowl angle to help reduce external oblique shock waves due to spillage and cowl geometry. To reduce mechanical complexity the inlet is designed with zero-bleed. To understand the impact on performance and shock overpressure caused by the inlet itself, several throat and diffuser designs were simulated. The computations utilised a Reynolds-averaged Navier-Stokes code. Inflow properties were held consistent with the operational characteristics of the NASA GRC 8′ × 6′ Supersonic Wind Tunnel (SWT) for experimental testing of the inlet of Mach 1·67 at a Reynolds number of 5·4 × 106. Stagnation pressure recovery performance for the baseline condition exceeded 94% at design mass flow rates, and reduced only slightly with increases in Mach number (consistent with theoretical predictions) and extension of cowl position. The simulations also showed that the relaxed compression surface combined with the near-zero cowl angle helps to significantly reduce external oblique shocks This is partly due to the reduced inlet spillage in combination with a reduced overall turning angle placed on the free-stream flow relative to the cowl shape.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 2013 

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References

1. Pawlowski, J.W., Graham, D.H., Boccadoro, C.H., Coen, P.G. and Maglieri, D.J. Origins and Overview of the Shaped Sonic Boom Demonstration Program, 43rd AIAA Aerospace Sciences Meeting and Exhibit, AIAA-2005-0005, Reno, NV, USA, 10 January 2005.Google Scholar
2. Smith, H. A review of supersonic business jet design issues, Aeronaut J, 2007, pp 761776.Google Scholar
3. Howe, D.C., Waithe, K.A. and JrHaering, E.A. Quiet SpikeTM Near Field Flight Test Pressure Measurements with Computational Fluid Dynamics Comparisons, 46th Aerospace Sciences Meeting and Exhibit, AIAA 2008-128, Reno, NV, USA, 7-10 January 2008.Google Scholar
4. Mattingly, J.D. Elements of Propulsion: Gas Turbines and Rockets, AIAA, Reston, Virginia, USA, 2006.Google Scholar
5. Seddon, J.J. and Goldsmith, E.L. Intake Aerodynamics, 2nd ed, AIAA, Reston, Virginia, USA, 1999.Google Scholar
6. Conners, T.R. and Howe, D.C. Supersonic Inlet Shaping for Dramatic Reductions in Drag and Sonic Boom Strength, 44th Aerospace Sciences Meeting and Exhibit, AIAA-2006-0030, Reno, NV, USA, 9-12 January 2006.Google Scholar
7. Stratford, and Tubbs, H. The maximum pressure rise attainable in subsonic diffusers, J Royal Aero, 1965, pp 275278.Google Scholar
8. Zha, G.C., Smith, D., Schwabacher, M., Rasheed, K., Gelsey, A. and Knight, D. High-performance supersonic missile inlet design using automated optimization, J Aircraft, November – December 1997, 34, (6),Google Scholar
9. Coyne, T.P. Simulations of a Low-Boom, Axisymmetric, External Compression Inlet with Bleed. MS Thesis, Department of Mechanical Science and Engineering, University of Illinois Urbana-Champaign, IL, USA, 2009.Google Scholar
10. Mani, M., Cary, A. and Ramakrishnan, S.V. A General purpose euler and navier-stokes solver for structured and unstructured grids, AIAA J Aircr, 2005, 42, (4), pp 991997.Google Scholar
11. Rybalko, M., Loth, E., Chima, R.V., Hirt, S. and Debonis, J.R. Micro-Ramps for External Compression Low-Boom Inlets, NASA TM-2010-216351, NASA Glenn Research Center, 2010.Google Scholar
12. Menter, F.R. Performance of popular turbulence models for attached and separated adverse pressure gradient fows AIAA J, 1992, 30, pp 20662072 Google Scholar
13. Coyne, T., Davis, D., Koncsek, J., Howe, D. and Loth, E., Simulations of a Low-Boom Axisymmetric External-Compression Inlet, AIAA Fluid Dynamics Conference, San Antonio, TX, USA, AIAA Paper 2009-4210, June 2009.Google Scholar
14. Tacina, K.M., Hirt, S.M., Conners, T.R., Merret, J.M. and Howe, D.C. Dynamic Analysis of Wind Tunnel Data from Isentropic Relaxed Compression Inlet, AIAA Paper 2007-5073, July 2007.Google Scholar
15. Conners, T.R., Merret, J.M., Howe, D.C., Tacina, K.M. and Hirt, S.M. Wind Tunnel Testing of an Axisymmetric Isentropic Relaxed External Compression Inlet at Mach 1·97 Design Speed, AIAA Paper 2007-5066, July 2007.Google Scholar
16. Rybalko, M. and Loth, E. Vortex Generators for a Single-Stream Low-Boom Inlet, AIAA Paper 2011-3803, June 2011.Google Scholar