Effective Far-Field Acoustic Prediction Method and Its Computational Aeroacoustics Applications

Abstract

A three-dimensional acoustic intensity-based method for the reconstruction and prediction of radiated acoustic fields is developed. The method is verified by examples of the propagation of multiple acoustic sources in a uniform flow and the acoustic scattering of a time-dependent source by a sphere. The effectiveness of acoustic intensity-based method in aeroacoustic applications is demonstrated by the accurate and efficient prediction of acoustic radiation from an axisymmetric duct intake using a hybrid computational aeroacoustics/acoustic intensity-based method approach. The results of the radiated acoustic field from the acoustic intensity-based method agree well with the solutions of computational aeroacoustics and the Ffowcs Williams-Hawkings integral equation. The acoustic intensity-based method is more efficient than other methods for the far-field acoustic prediction and can use the input acoustic data from an open surface instead of a closed surface, such as the Ffowcs Williams-Hawkings surface.