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Assessment of surface roughness for a ‘silent’ aircraft

Part of: Sustainable Aerospace

Published online by Cambridge University Press:  27 January 2016

Y. Liu
Y. Liu*
Affiliation:
Department of Engineering, University of Cambridge, Cambridge, UK
*
[email protected]
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Abstract

Boundary-layer noise produced by rough surfaces is a potential contributor to airframe noise. In this paper, an attempt is made to assess the surface roughness noise for a conceptual Silent Aircraft design SAX-40 using a prediction model described in previous theoretical work (Liu and Dowling(12)). Estimates of three idealised test cases show that surface roughness could produce a relatively high noise level and enhance the trailing-edge noise somewhat. Roughness height and roughness density are two significant parameters which affect surface roughness noise, with roughness height having the more dominant effect. The distribution of roughness noise sources decreases in the streamwise direction on the SAX-40 surface. Two candidate rough surfaces are selected for SAX-40 to keep surface roughness noise at a negligible level and to meet an aggressive noise target.

Type
Research Article
Information
The Aeronautical Journal , Volume 117 , Issue 1189 , March 2013 , pp. 283 - 298
Copyright
Copyright © Royal Aeronautical Society 2013 

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Footnotes

p1

Currently at: Department of Mechanical Engineering Sciences, University of Surrey, Guildford, UK

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