Optimum and off-optimum properties of circumferentially segmented duct liners are compared with those of uniform liners to identify any potential benefits of circumferentially segmented liners. High- and low-order spinning-mode sources are considered in the study. The solution for the segmented liner is obtained by a multimodal expansion of the segmented-liner eigenmodes in terms of a series of hardwall duct models. The coefficients in the hard-wall series are obtained by using Galerkin's method. Results show that for some frequencies and duct lengths, circumferentially segmented liners scatter energy equally between a higher and lower order circumferential wave number. Studies for higher order spinning-mode sources show that an optimized s...
This thesis contains original research into the propagation of sound in acoustically lined ductswith...
In this article the attenuation of broadband noise in an acoustically-lined circular-section duct is...
The propagation of spinning mode sound was considered for a cylindrical duct with sheared steady flo...
The acoustic fields and transmission losses produced in semi-infinite circular ducts with peripheral...
An experiment was conducted to investigate mode redistribution in lined circular ducts with circumfe...
A correlating equation relating the optimum acoustic impedance for the wall lining of a circular duc...
Results are presented from detailed analytical studies made to define methods for obtaining improved...
An acoustical field theory for axisymmetric, multisectioned lined ducts with uniform flow profiles w...
A detailed theoretical study of the acoustic propagation of spinning modes in acoustically treated o...
New calculations show that segmenting is most efficient at high frequencies with relatively long duc...
Sound wave propagation in a soft-walled rectangular duct with steady uniform flow was investigated a...
Central processor unit times and memory requirements for a commonly used solver are compared to that...
A new acoustic liner design procedure based upon model cut-off ratio is outlined. Proposed experimen...
Axial segmentation of acoustically absorbing liners in rectangular, circular or annual duct configur...
An extensive duct acoustics propagation study is presented that has been conducted to assess the des...
This thesis contains original research into the propagation of sound in acoustically lined ductswith...
In this article the attenuation of broadband noise in an acoustically-lined circular-section duct is...
The propagation of spinning mode sound was considered for a cylindrical duct with sheared steady flo...
The acoustic fields and transmission losses produced in semi-infinite circular ducts with peripheral...
An experiment was conducted to investigate mode redistribution in lined circular ducts with circumfe...
A correlating equation relating the optimum acoustic impedance for the wall lining of a circular duc...
Results are presented from detailed analytical studies made to define methods for obtaining improved...
An acoustical field theory for axisymmetric, multisectioned lined ducts with uniform flow profiles w...
A detailed theoretical study of the acoustic propagation of spinning modes in acoustically treated o...
New calculations show that segmenting is most efficient at high frequencies with relatively long duc...
Sound wave propagation in a soft-walled rectangular duct with steady uniform flow was investigated a...
Central processor unit times and memory requirements for a commonly used solver are compared to that...
A new acoustic liner design procedure based upon model cut-off ratio is outlined. Proposed experimen...
Axial segmentation of acoustically absorbing liners in rectangular, circular or annual duct configur...
An extensive duct acoustics propagation study is presented that has been conducted to assess the des...
This thesis contains original research into the propagation of sound in acoustically lined ductswith...
In this article the attenuation of broadband noise in an acoustically-lined circular-section duct is...
The propagation of spinning mode sound was considered for a cylindrical duct with sheared steady flo...