A second-order uniformly valid expansion is obtained by using the method of multiple scales for the 'non-linear wave propagation in a circular duct whose walls are lined with a non-linear acoustic material. The acoustic material is characterized by an empirical, non-linear impedance in which the ins
Sound propagation in acoustically lined elliptical ducts
โ Scribed by Oliveira, J.M.G.S.; Gil, P.J.S.
- Book ID
- 121804350
- Publisher
- Elsevier Science
- Year
- 2014
- Tongue
- English
- Weight
- 623 KB
- Volume
- 333
- Category
- Article
- ISSN
- 0022-460X
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The propagation of sound in elliptic ducts has been investigated as a model case to indicate the acoustic effects of departures from symmetry in a circular duct. The cut-off frequencies of the higher order circumferential modes in an elliptic duct have been calculated for various duct eccentricities
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