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Effect of Leading-edge Geometry and Aerodynamic Loading on Receptivity to Acoustic Disturbances

  • P. W. Hammerton
  • E. J. Kerschen
Conference paper
Part of the IUTAM Symposia book series (IUTAM)

Abstract

A theoretical analysis is presented for the effects of the nose radius and aerodynamic loading of a body on leading-edge receptivity. We consider linear, time-harmonic disturbances to a two-dimensional, low Mach number flow past a cambered airfoil with parabolic leading edge. Asymptotic methods based on large Reynolds number are used, supplemented by numerical results. The body nose radius enters the theory through a Strouhal number S, and the mean aerodynamic loading enters the theory through a leading-edge loading parameter μ. For most values of μ, the receptivity level decreases with increasing S. At fixed S, the introduction of modest aerodynamic loading produces a reduction in receptivity, but as the loading is increased towards the point at which the mean boundary-layer flow separates, a marked increase in receptivity coefficient is observed. Obliquely incident acoustic waves are found to produce much higher receptivity levels than parallel waves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2000

Authors and Affiliations

  • P. W. Hammerton
    • 1
  • E. J. Kerschen
    • 2
  1. 1.School of MathematicsUniversity of East AngliaNorwichUK
  2. 2.Department of Aerospace & Mechanical EngineeringUniversity of ArizonaTucsonUSA

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