• Corpus ID: 30767098

Modelling and Characterization of Perforates in Lined Ducts and Mufflers

@inproceedings{Elnady2004ModellingAC,
  title={Modelling and Characterization of Perforates in Lined Ducts and Mufflers},
  author={Tamer Elnady},
  year={2004}
}
Increased national and international travel over the lastdecades has caused an increase in the global number ofpassengers using different means of transportation. Greateffort is being directed to improving the noisy environment inthe residential community. This is to face the growing strictnoise requirements which are implemented by international noiseregulatory authorities, governments, and local airports. Thereis also a strong competition between different manufacturers tomake their products… 

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References

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Acoustic liners are widely used to attenuate sound waves inside aircraft jet engines. In most cases, the existence of hard strips in the lined ducts is inevitable. Previous research has proved that

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There is evidence that the sound field radiating from a turbofan engine inlet can be strongly modulated by the presence of intercostal strips in the liner. The major concern here is that this

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Lasting increasing of air traffic will only be feasible if noise pollution near airports, due to aircraft flyover, is significantly reduced. Among acoustic emissions from the aircraft, engine noise,

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In most turbofan engine intakes, the acoustically lined region consists of several liner segments which are separated by longitudinal hard-walled intercostal strips or splices. Measurements indicate

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A simple method is presented for modeling perforated muffler components such as concentric resonators with perforated flow tube, and expansion chambers and reverse flow chambers with perforated inlet
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