Acoustic radiation from a thin airfoil in nonuniform subsonic flows

Noise resulting from the interaction of impinging unsteady vortical disturbances on a thin airfoil in subsonic flow is directly calculated using unsteady aerodynamic theory. Exact expressions for the far-field acoustic pressure, intensity, and total acoustic energy radiated are derived in terms of the Fourier transform of the unsteady pressure along the airfoil surface and account for both dipole and quadrupole effects. We provide benchmark results for the case of a thin airfoil for comparison with future calculations for a loaded airfoil

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