A vorticity based aeroacoustic prediction for the noise emission of a low-speed turbulent internal flow
Turbulent internal flows are known to generate intense noise as, well as surface pressure fluctuations. Numerically predicting the noise emission near the prescribed boundaries requires that the sound-generating turbulent flow be adequately represented and described. The k-epsilon method provides a promising tool for obtaining the unsteady characteristics of a realistic turbulent flow interacting with a rectangular flat plate undergoing "ground effect". The far-field acoustic calculation is facilitated by the Kambe model (from Lighthill's theory) and an original post-processor has been developed to determine the far-field spectra and the source term characteristics. In pre-processed turbulent confined flows inside a rectangular enclosure, computations using the k-epsilon method, coupled with a convenient post-processor, is used to predict noise radiation over a wide range of frequencies and geometrical configurations. The portability and effectiveness of the present method, however, start to be less evident when the turbulent flow has very chaotic internal features; these suggest the need for a wider computational aeroacoustic domain and a new procedure suitable for the turbulent flow representation. (C) 2003 Elsevier Science Ltd. All rights reserved.
aeroacoustics turbulent flow