Blown flap noise prediction

Theoretical and experimental developments of flow-surface interaction noise with a particular emphasis on blown-flap noise were reviewed. Several blown-flap noise prediction methods were evaluated by comparing predicted acoustic levels, directivity, and spectra with a recently obtained data base. A prediction method was selected and a detailed step-by-step description of this method was provided to develop a computer module to calculate one-third octave band frequency spectra at any given location in the far-field for under-the-wing and upper surface blown configurations as a function of geometric and operational parameters.