Scattering of Acoustic Waves by a Rotor

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Scattering of Acoustic Waves by a Rotor

• Michaela M. Logue
• Advisor Hafiz M. Atassi

NDSEG Fellow
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High By-Pass Turbofan Engine
Rotor
Stator
GP7000
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1 Image from GEAE
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An Annulus with a Rotor and Stator
Rotor
Stator
Geometry Considered
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Previous Developments

• 2D integral equation theory LINC
• 2D numerical code, loaded and unloaded blades
  CASGUST
• 3D eigenvalue code
• 3D unloaded, efficient 3D_U
• 3D loaded, efficient 3D_L
• 3D arbitrary airfoil 3D_LSM

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Formulation for 3D Codes
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Narrow Annulus Case Acoustic Coefficients
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Full Annulus Case
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1st Aim

• 1. How much will the scattering process affect
  the upstream radiated sound?

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2nd Aim

• 2. How significant are the effects of resonance
  and what are the resulting frequencies and
  intensities of these interactions?

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Modifying on The Governing Equations

• The axis will be fixed to the rotor, this frame
  of reference will account for the centrifugal and
  Coriolis forces.

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The New Computational Domain
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Validations

• Comparison with 3D_U or 3D_L codes.
• Experimental results.

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Thanks and Acknowledgments

• Dr. Atassi
• Dr. Feng
• Dr. Ali
• Dr. El Hadidi
• Dr. Vinogradov
• Mr. Zhang