Acoustic Finite Element Analysis of a Slit Model with Consideration of Air Viscosity

In very narrow pathways, the speed of sound propagation and the phase of sound waves change due to the air viscosity. We have developed a new finite element method (FEM) that includes the effects of air viscosity for modeling a narrow sound pathway. This method is developed as an extension of the existing FEM for porous sound-absorbing materials. The numerical calculation results for several three-dimensional slit models using the proposed FEM are validated against existing calculation methods.

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

• Simulation
• FEM
• air viscosity
• slit.

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