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Acoustical localized approximation for acoustical fields with axicon angles
Gérard Gouesbet1,2, Leonardo A Ambrosio1,2
1CORIA-UMR 6614-Normandie Université. CNRS-Université et INSA de Rouen. Campus Universitaire du Madrillet. 76800, Saint-Etienne du Rouvray, France.
The Journal of the Acoustical Society of America
|August 10, 2026
Summary
A new acoustical localized approximation efficiently calculates beam shape coefficients for acoustic fields. This method, adapted from electromagnetics, shows limitations for acoustic fields with axicon angles.
Area of Science:
- Acoustics
- Wave Physics
- Optics
Background:
- Acoustic fields are often expanded using spherical wave functions.
- Expansion coefficients are crucial for characterizing acoustic beams.
- Electromagnetic beam techniques offer potential for acoustic field analysis.
Purpose of the Study:
- To develop an efficient method for calculating expansion coefficients of acoustic fields.
- To adapt and apply localized approximation techniques from electromagnetics to acoustics.
- To investigate the validity of the acoustical localized approximation for specific beam types.
Main Methods:
- Expansion of acoustic fields over spherical wave functions.
- Development of a localized approximation technique for acoustic fields, particularly Gaussian beams.
- Adaptation of methods used for electromagnetic beams.
Main Results:
- An efficient and rapid method for evaluating beam shape coefficients has been established.
- The acoustical localized approximation is effective for a broad range of acoustic fields, including Gaussian beams.
- The approximation's validity is limited for acoustic fields exhibiting an axicon angle.
Conclusions:
- The developed acoustical localized approximation offers significant computational advantages for acoustic field analysis.
- The method's applicability is constrained in scenarios involving acoustic fields with axicon angles.
- Further research may be needed to refine the approximation for axicon-like acoustic fields.
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