The EU project FACE (Friendly Aircraft Cabin Environment) aims to improve the environmental comfort in aircraft cabins. As part of this project, this paper focuses on the reduction of noise in aircraft cabins. For modern aircraft flying at cruise conditions, this cabin noise is known to be dominated by turbulent boundary layer noise. The purpose of this work is to reduce the resulting sound pressure levels in the cabin by means of optimised sound absorbing trim panels with quarter-wave resonators. Sound absorption with quarter-wave resonators is mainly realised by dissipation of sound energy as a result of viscous and thermal losses. The viscothermal wave propagation of the air inside the resonators is efficiently and accurately described by the so-called low reduced frequency model. By optimisation of the dimensions of the resonators, desired sound absorption characteristics can be obtained for different specified frequency ranges. This means that the panels can be tailored to different positions in the aircraft cabin with different prevailing sound pressure levels. Results of optimisations for various frequency ranges show that a very good agreement is obtained between the desired and the calculated absorption curves. With the same optimisation procedure, panels have also been tuned for the dominant frequency range of a sound spectrum measured in a modern aircraft. Experimental validation of the numerically predicted optimal configurations, by means of impedance tube measurements, shows that a fairly good agreement is obtained between the numerical and experimental results.
|Title of host publication||ICSV11|
|Editors||N.I. Ivanov, M.J. Crocker|
|Place of Publication||St.Petersburg Rusland|
|Publication status||Published - 5 Jul 2004|
|Event||11th International Congress on Sound and Vibration, ICSV 2004 - St. Petersburg, Russian Federation|
Duration: 5 Jul 2004 → 8 Jul 2004
Conference number: 11
|Conference||11th International Congress on Sound and Vibration, ICSV 2004|
|Period||5/07/04 → 8/07/04|
Hannink, M. H. C., Wijnant, Y. H., & de Boer, A. (2004). Optimised Sound Absorbing Trim Panels for the Reduction of Aircraft Cabin Noise. In N. I. Ivanov, & M. J. Crocker (Eds.), ICSV11 (pp. 1855-1862). St.Petersburg Rusland: ICSV11.