Neutral Damping Boundary in the Transonic Regime

  • I. Teipel
Conference paper
Part of the International Union of Theoretical and Applied Mechanics book series (IUTAM)

Summary

Linearized theory for supersonic flow past oscillating profiles indicates the possibility of instability of pitching oscillations for low frequencies. If the Mach number M approaches one, linearized theory fails. The influence of the thickness ratio cannot be neglected. Even the second-order theory becomes unreliable, when the bow shock wave detaches. In order to get results for this regime an approximate method similar to that of the “local linearization method” for the steady case has been developed. For M = 1, a linear parabolic differential equation has been already established; now for M > 1 a linear hyperbolic differential equation will be derived. The neutral damping boundary will be discussed as a function of the thickness ratio and of the Mach number.

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References

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    Landahl, M.T.: Unsteady Transonic Flow. International Series of Monographs in Aeronautics and Astronautics. Division II: Aerodynamics. Vol. 2 Pergamon Press, Oxford/London/New York/Paris 1961.Google Scholar
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Copyright information

© Springer-Verlag, Berlin/Heidelberg 1976

Authors and Affiliations

  • I. Teipel
    • 1
  1. 1.Institut für MechanikTechn. Universität HannoverGermany

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