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The propagation of sound in ducts lined with circumferentially non-uniform admittance of the form ηo+ηq exp (iqθ)

✍ Scribed by P.G. Vaidya


Publisher
Elsevier Science
Year
1985
Tongue
English
Weight
652 KB
Volume
100
Category
Article
ISSN
0022-460X

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✦ Synopsis


In this paper, closed form solutions are obtained to a problem of sound propagation in a duct with circumferentially non-uniform admittance. Traditionally, solutions to duct problems have been sought in terms of modes which can be expressed as products of functions of space and time co-ordinates. This method fails when the boundary conditions are non-uniform. In the text of the paper, non-separable solutions are developed to obtain a closed form solution to the problem. The non-separable modes are a sum of sub-modes, which satisfy the wave equation but not the boundary conditions. Expressions are obtained for the sub-modal distribution functions, which ensure that together the sub-modes shall form a wave packet which will satisfy the boundary conditions.