Optimization of Two-Dimensional Acoustic Diffuser Surfaces Using Kirchhoff Approximation in MATLAB

Abstract

This study numerically analyzes the angular reflection performance of two-dimensional acoustic diffuser surfaces using the Kirchhoff approach in MATLAB. In the study, ideal Lambertian and band-limited diffuser types are compared under different incidence angles and surface geometries (slope and recess width). The aim is to reveal the effect of surface design parameters on the angular distribution of sound energy and to contribute to the design of structures that provide homogeneous reflection. The results show that Lambertian surfaces provide ideal reflection only at normal incidence angles; band-limited diffusers can direct the energy in a controlled manner within a certain angle range. It is observed that the reflection intensity decreases and the distribution widens with the increase in slope. This situation reveals the decisive role of surface geometry on acoustic performance. The findings provide an important basis for surface optimization in acoustic design applications.

Keywords

• Two-dimensional diffuser
• Acoustic energy distribution
• Matlab
• Frequency response

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