Journal of Visualization

, Volume 6, Issue 2, pp 195–203 | Cite as

Visualization of unsteady shock oscillations in the High-enthalpy flow field around double cones

  • Jagadeesh G. 
  • Hashimoto T. 
  • Naitou K. 
  • Sun M. 
  • Takayama K. 
Article

Abstract

The presence of an adverse pressure gradient, shock/shock interaction and shock wave/boundary layer interaction often induces flow separation around bodies. However, the effect of dissociated flow on separated flow characteristics, especially at hypersonic speeds, is still not clear, and considerable differences are observed between experiments and numerical simulations. In this investigation, the unsteady separated flow features around double cones are visualized in the Shock Wave Research Center (SWRC) free-piston driven shock tunnel at a nominal Mach Number of 6.99 using multiple optical techniques. The time resolved shock structure oscillations in the flow field around double cones (first cone, semi-apex angle = 25°; second cone, semi-apex angles=50°, 65°, 68° and 70°) have been visualized using a high-speed image converter camera (IMACON) at a nominal stagnation enthalpy of 4.8 MJ/kg. In addition, flow visualization studies around the double cone is also carried out using Schlieren and double exposure holographic interferometry in order to precisely locate the separation point and measure the separation length. The presence of a triple shock structure in front of the second cone and a non-linear unsteady shock structure oscillation in the flow field are the significant results from visualization studies on the 25° /65°, 25° /68° and 25°/70° double cones. On the other hand, the flow field around 25° /50° is relatively steady and Type V shock/shock interaction is observed. Illustrative numerical simulation studies are carried out by solving N-S equations to complement the experiments. The simulated flow features around a double cone agree well qualitatively with experiments.

Keywords

Visualization Separated hypersonic flow Shock tunnel 

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References

  1. Chanetz, B. Benay, R., Bousquet, J. M., Bur, R., Pot, T., Grassp F. and Moss, J., Experimental and Numerical Study of the Laminar Separation in Hypersonic Flow, AerospaceScience andTechnology, 3(1998), 205.CrossRefGoogle Scholar
  2. Edney, B., Anomalous Heat Transfer and Pressure Distribution on Blunt Bodies at Hypersonic Speeds in the Presence of an Impinging Shock, FFA Report, (1968), 115.Google Scholar
  3. Rudy, D. H., Thomas, J. L., Ajay Kunar, P., Gnoffo A. and Chakravarthy, S. R., Computation of Laminar Hypersonic Compression Corner FlowsAIAA J., 29-7(1991), 1108.Google Scholar
  4. Jagadeesh, G., Reddy, K. P. J., Naitou, K., Hashimoto, T., Sun, M. and Takayama, K., Study of the Separated High Enthalpy Flow Around a Double Cone, AIAA, (2002), 2002–0299.Google Scholar
  5. Jean-PaulDavis and Bradford Sturtevant, Separation Length in High-Enthalpy Shock/Boundary Layer Interaction,Phyic of Fluids, 12-10(2000), 2661.CrossRefGoogle Scholar
  6. Olejniczak, J., Wright, M. J. and Candler, G.V., Numerical Study of Inviscid Shock Interactions on Double-Wedge Geometries,J. Fluid Mechanics, 352(1997), 1.MATHCrossRefGoogle Scholar
  7. Hashimoto, T., Naitou, K. and Takayama, K., Density Measurement Over Sphere in Free Piston Driven Shock Tunnel, AIAA (2001), 2001–1770.Google Scholar
  8. Takayama, K., Application of Holographic Interferometry to Shock Wave Research, Proc. of the Society of Photo-Optical Instrumentation Engineers, 398(1983), 174.Google Scholar
  9. Sun, M., Numerical and Experimental Studies of Shock Wave Interaction With Bodies, Ph.D. Thesis, Tohoku University, Japan, (1999).Google Scholar
  10. Wright, M. J., Sinha, K., Olejniczak, J. and Candler, G. V., Numerical and Experimental Investigation of Double-Cone Shock Interactions, AIAA J., 38-12(2000), 2268.CrossRefGoogle Scholar

Copyright information

© The Visualization Society of Japan 2003

Authors and Affiliations

  • Jagadeesh G. 
    • 1
  • Hashimoto T. 
    • 2
  • Naitou K. 
    • 2
  • Sun M. 
    • 2
  • Takayama K. 
    • 2
  1. 1.Dept. of Aerospace EngineeringIndian Institute of ScienceBangaloreIndia
  2. 2.Shock Wave Research Center, Institute of Fluid ScienceTohoku UniversitySendaiJapan

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