CUED Publications database

Far-field noise prediction for jets using large-eddy simulation and Ffowcs Williams–Hawkings method

Naqavi, IZ and Wang, ZN and Tucker, PG and Mahak, M and Strange, P (2016) Far-field noise prediction for jets using large-eddy simulation and Ffowcs Williams–Hawkings method. International Journal of Aeroacoustics, 15. pp. 757-780. ISSN 1475-472X

Full text not available from this repository.

Abstract

© 2016, © The Author(s) 2016. Large-eddy simulations are performed for hot and cold jets with and without a flight stream. The acoustic and flight stream Mach numbers are 0.875 and 0.3, respectively. The temperature ratios for the hot and cold jets are 2.7 and 1.0, respectively. The mean flow field results are in good agreement with the measurements. The Ffowcs Williams–Hawkings equation is used to predict far-field noise. Several axisymmetric Ffowcs Williams–Hawkings surfaces at increasing radial distances are used. They show that the surfaces closer to the jet can be affected by the hydrodynamic pressure. It is important to close the Ffowcs Williams–Hawkings surfaces at the ends to account for all the acoustic signals emanating from the jet. In this work, 11 end discs are used at the downstream end of the Ffowcs Williams–Hawkings surface. It is found that the simple averaging processes to cancel hydrodynamic sound at the end discs are insufficient for slowly decaying jets. In such cases, a partially closed disc can be a better choice. To remove hydrodynamic signals, a filtering scheme for the end discs is suggested. For slowly decaying jets, this gives better results.

Item Type: Article
Subjects: UNSPECIFIED
Divisions: Div A > Fluid Mechanics
Div A > Turbomachinery
Depositing User: Cron Job
Date Deposited: 17 Jul 2017 19:18
Last Modified: 21 Sep 2017 01:39
DOI: