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Abstract

The present paper is oriented at the definition of a series of validation test cases for the far-field subsonic formulation of Farassat in the time domain, solving the Lighthill analogy for aeroacoustics in the Ffowcs William-Hawkings formulation for far-field noise predictions. The focus will be on the definition, validation and verification of four test cases for far-field acoustic propagation. The test cases are: (i) a rotating rotor with a pre-defined body force, (ii) a translating and rotating small disk case with a moving observer, (iii) a conventional helicopter rotor case, (iv) and the consistency test known as the Isom thickness noise. The acoustic pressure signature, sound pressure level and directivity have been calculated for each test case. Graphical outputs and comparisons of results with those of analytical solutions are presented.

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Validation of a Time Domain Formulation for Propeller Noise Prediction

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