Broadband shock-associated noise predictions

Philip John Morris, Steven A E Miller

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Broadband shock-associated noise (BBSAN) is generated when a jet operates off-design. This can occur in both military fighter aircraft turbojet engines and commercial turbofan engines, particularly at cruise conditions. The noise is generated by the interaction between the turbulence in the jet shear layer and the jet's shock cell structure. The present paper describes a model for BBSAN that uses steady RANS CFD to describe the jet flow and to provide information on the turbulence scales. The acoustic model is based on a rearrangement of the equations of motion into a propagation component (the linearized Euler equations) and a source component, which depends on products of the turbulent fluctuations and the shock cell pressure perturbations. A model is introduced to describe the statistical properties of the turbulence and the shock cell structure is determined from the RANS simulations. Predictions are made for circular and rectangular single stream jets, both unheated and heated, and both under- and over-expanded conditions. Comparisons of the predicted BBSAN spectra are made with experiments.

Original languageEnglish (US)
Title of host publication8th European Conference on Noise Control 2009, EURONOISE 2009 - Proceedings of the Institute of Acoustics
Volume31
EditionPART 3
Publication statusPublished - 2009
Event8th European Conference on Noise Control 2009, EURONOISE 2009 - Edinburgh, United Kingdom
Duration: Oct 26 2009Oct 28 2009

Other

Other8th European Conference on Noise Control 2009, EURONOISE 2009
CountryUnited Kingdom
CityEdinburgh
Period10/26/0910/28/09

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All Science Journal Classification (ASJC) codes

  • Acoustics and Ultrasonics

Cite this

Morris, P. J., & Miller, S. A. E. (2009). Broadband shock-associated noise predictions. In 8th European Conference on Noise Control 2009, EURONOISE 2009 - Proceedings of the Institute of Acoustics (PART 3 ed., Vol. 31)