Acoustic Analysis with Consideration of Damping Effects of Air Viscosity in Sound Pathway

Sound pathways in the enclosures of small earphones are very narrow. In such narrow pathways, the speed of sound propagation and the phase of sound waves change because of the air viscosity. We have developed a new finite element method that includes the effects of damping due to air viscosity for modeling the sound pathway. This method is developed as an extension of the existing finite element method for porous sound-absorbing materials. The numerical calculation results using the proposed finite element method are validated against the existing calculation methods.

Authors:

• M. Sasajima
• M. Watanabe
• T. Yamaguchi
• Y. Kurosawa
• Y. Koike

Keywords:

• Simulation
• FEM
• air viscosity
• damping.

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