|Author||Perrey-Debain, Emmanuel ♦ Ville, Jean-Michel ♦ Nennig, Benoit|
|Subject Domain (in DDC)||Computer science, information & general works ♦ Data processing & computer science|
|Subject Keyword||Numerical Impedance Matrix ♦ Herschel-quincke Tube Concept ♦ Passive Device ♦ Acoustic Velocity ♦ Exact Shape ♦ Semi-analytical Model ♦ Fan Noise ♦ Normal Acoustic Velocity ♦ Plane Wave ♦ High Frequency Mode ♦ Duct-tube Interface ♦ Main Wave Guide ♦ Discrete Modal Analysis ♦ New Mixed Analytical-numerical Approach ♦ Main Duct|
|Abstract||The Herschel-Quincke (HQ) tubes, consisting in putting tubes in derivation along a main wave guide, are used as passive devices to control fan noise. In order to assess the efficiency of this system, analytical and semi-analytical models proposed in the literature all rely on the assumption that only plane waves are allowed to propagate in the tube which then restrict the pressure and the normal acoustic velocity to be constant over the duct-tube interface. We show that these simplifications are too limited especially when dealing with high frequency modes in the main duct. To make some progress, a new mixed analytical-numerical approach is proposed. The method, based on the discrete modal analysis of the tube allows to take into account its exact shape as well as the non-uniformity of the acoustic velocity at the interface. 1|
|Educational Role||Student ♦ Teacher|
|Age Range||above 22 year|
|Education Level||UG and PG ♦ Career/Technical Study|
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