Acoustic propagation in nearly annular ducts

✍ Scribed by S. Sridhar; A.H. Nayfeh

• Publisher: Elsevier Science
• Year: 1978
• Tongue: English
• Weight: 574 KB
• Volume: 58
• Category: Article
• ISSN: 0022-460X
• DOI: 10.1016/s0022-460x(78)80057-1

✦ Synopsis

The propagation of acoustic waves in a duct of nearly annular cross-section is investigated. A method, based on a perturbation technique, is developed for calculating the wavenumbers of the propagating modes. Numerical results are presented for the case of (1) an annular duct having an elliptical outer boundary and a circular inner boundary, and (2) a cylindrical duct having an elliptical boundary. The results of the latter case compare favorably with those previously published, for eccentricities up to 0.6. Major advantages of the present method, as compared with previously used methods, are its generality and the relative ease of the computation involved, provided the boundaries do not deviate drastically from circles.