A simplified model for thin acoustic screens

Area of Science:

• Acoustics
• Materials Science
• Physics

Background:

• Porous layer modeling is crucial in acoustics.
• Existing pressure jump models have limitations.
• Transfer matrix methods are widely used for layered materials.

Purpose of the Study:

• To propose a generalized pressure jump model for thin porous layers.
• To simplify existing models using linear approximations and physical assumptions.
• To reduce the complexity of equivalent fluid parameters and the transfer matrix.

Main Methods:

• Derivation of a transfer matrix model using matrix exponentials.
• Application of first-order expansions for linear approximation.
• Simplification of the resulting matrix based on physical hypotheses.
• Validation across diverse backing conditions and thin film types.

Main Results:

• A generalized and simplified model for thin porous layers.
• Reduced expressions for equivalent fluid parameters.
• A sparser transfer matrix, enhancing computational efficiency.
• Validation confirmed model accuracy for normal to grazing incidence.

Conclusions:

• The proposed model offers a more efficient and generalized approach to analyzing thin porous layers.
• The simplification of parameters and matrix structure aids in practical applications.
• The model's robustness is demonstrated across various acoustic scenarios.