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arXiv · 1809.03277

Acoustic Propagation in lined ducts with varying cross-section using a Mild-Slope approximation

Maaz Farooqui·Yves Aurégan·Vincent Pagneux
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Abstract

A modelling of low-frequency sound propagation in slowly varying ducts with smoothly varying lining is proposed leading to an acoustic mild-slope equation analogue to the with mild-slope equation for water waves. This simple 1D Mild Slope Equation is derived by direct application of the Galerkin method. It is shown that the acoustic mild-slope equation can serve as a good alternative to computationally expensive Helmholtz equations to solve such kind of problem. The results from this equation agrees well with FEM based solutions of Helmholtz equation.

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Maaz Farooqui, Yves Aurégan, Vincent Pagneux. 2018-09-10. Acoustic Propagation in lined ducts with varying cross-section using a Mild-Slope approximation. https://arxiv.org/abs/1809.03277

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