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Updated: Aug 23, 2026

Synthetic, Multi-Layer, Self-Oscillating Vocal Fold Model Fabrication
Published on: December 2, 2011
Rational approximations of viscous losses in vocal tract acoustic modeling
Reiner Wilhelms-Tricarico1, Richard S McGowan
1CReSS LLC, Lexington, Massachusetts 01007, USA. rewt@cressllc.net
Abstract:
The modeling of viscous losses in acoustic wave transmission through tubes by a boundary layer approximation is valid if the thickness of the boundary layer is small compared to the hydraulic radius. A method was found to describe the viscous losses that extends the frequency range of the model to very low frequencies and very thin tubes. For higher frequencies, this method includes asymptotically the spectral effects of the boundary layer approximation. The method provides a simplification for the rational approximation of the spectral effects of viscous losses.
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