Modeling transient sound propagation over an absorbing plane by a half-space interpolated time-domain equivalent...

Area of Science:

• Acoustics
• Computational Mechanics
• Wave Propagation

Background:

• Modeling transient sound propagation over surfaces is crucial for understanding acoustic phenomena.
• Conventional methods often struggle to accurately account for the reflective properties of absorbing surfaces in the time domain.
• The interpolated time-domain equivalent source method (ITDESM) offers a framework for such simulations.

Purpose of the Study:

• To introduce a half-space interpolated time-domain equivalent source method (ITDESM) for transient sound propagation over absorbing planes.
• To develop a formulation incorporating a closed-form transient half-space Green's function that accounts for surface reflection effects.
• To validate the proposed method's accuracy and robustness in reconstructing transient sound fields under various conditions.

Main Methods:

• Development of the half-space ITDESM using a novel closed-form transient half-space Green's function for an absorbing infinite plane.
• The new Green's function explicitly includes the reflection effects of the absorbing surface, unlike free-field Green's functions.
• Numerical simulations of transient pressure fields from monopole sources in front of an absorbing plane, including noise analysis.

Main Results:

• The half-space ITDESM successfully reconstructs transient sound fields in both spatial and temporal domains with high accuracy.
• The method demonstrates robustness when measurement noise is considered during the reconstruction process.
• Experimental validation using an impacted steel plate over glass wool confirms the method's effectiveness under practical conditions.

Conclusions:

• The proposed half-space ITDESM is a powerful and accurate tool for modeling transient sound propagation over absorbing surfaces.
• The incorporation of a specific half-space Green's function significantly improves the modeling of reflection effects.
• The method's validated performance makes it suitable for real-world acoustic engineering applications.