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Showing 1 to 8 of 8 for “"Perforated Plates"”.
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Sound radiation from perforated plates
Perforated plates are quite often used as a means of engineering noise control to reduce the sound radiated by structures. However, there appears to be a lack of representative models to determine the sound radiation from a perforated plate. The aim of this thesis is to develop such a model that …
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Performance of mild steel perforated plates as a blast wave mitigation technique
… geometric parameters on the performance of perforated plates as a blast wave mitigation technique. Results of experimental and numerical simulations are reported. The main objective of this investigation was to determine the effects of the perforated plate hole size on the blast wave …
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Acoustic Scattering by Gratings
… thesis considers the sound scattering by thin perforated plates, to further understand and develop analytic models for porous noise reduction metamaterials. The semi-analytic Fokas method is extended to periodic geometries, and the resulting integral equation, recognised as a generalised …
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Experiments and Impedance Modeling of Liners Including The Effect of Bias Flow
The study of normal impedance of perforated plate acoustic liners including the effect of bias flow was studied. Two impedance models were developed, by modeling the internal flows of perforate orifices as infinite tubes with the inclusion of end corrections to handle finite length effects. These …
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Development of Velocity Profile Generating Screens for Gas Turbine Components
… match real world conditions through the use of perforated plates. The velocity profile generating screen is an array of jets arranged in a manner to produce sections of different solidities, a ratio of area that obstructs fluid flow compared to that of the total area. In an effort to better …
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Aeroacoustics of perforated drag plates for quiet transport aircraft
… primarily on aeroacoustic tests and analysis of perforated drag plates. The idea behind a quiet spoiler or drag rudder is to alter the noise production mechanism by perforating the drag plates. The hypothesis is that the large length scales responsible for the noise radiated by unsteady vortical …
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The effects of freestream turbulence on the drag of a sphere
… scale Λ were manipulated by using orificed perforated plates. The proper combination of orificed perforated plate hole diameter, sphere size, and sphere location enabled the independent variations of turbulence intensity and relative integral length scale (Λ/d) from 1.8% to 10.7% and from …
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The structural behavior of cold-formed steel members with perforated elements
… of the instability and post-buckling strength of perforated elements. In this investigation, the buckling loads and post-buckling strength of stiffened and unstiffened compression elements having single circular and square holes have been studied analytically by using the finite element method. …