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arXiv · 2212.13795

Acoustic Equation in a Lossy Medium

Tapan K. Sengupta·Prasannabalaji Sundaram·Aditi Sengupta
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Abstract

Here, the acoustic equation for a lossy medium is derived from the first principle from the linearized compressible Navier-Stokes equation without Stokes' hypothesis. The dispersion relation of the governing equation is obtained, which exhibits both the dispersive and dissipative nature of the acoustic perturbations traveling in a lossy medium, depending upon the length scale. We specifically provide a theoretical cut-off wave number above which the acoustic equation represents a diffusive nature. Such a behavior has not been reported before, as per the knowledge of the authors.

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Tapan K. Sengupta, Prasannabalaji Sundaram, Aditi Sengupta. 2022-12-28. Acoustic Equation in a Lossy Medium. https://arxiv.org/abs/2212.13795

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