Journal of Vibration and Sound

Journal of Vibration and Sound

Performance Assessment of the Transfer Matrix Method in Predicting the Acoustic Performance of Reactive Expansion and Dissipative Silencers with Absorptive Material

Document Type : research article

Authors
1 Imam Khomeini International University
2 Imam Khomeini Internation University
Abstract
Noise control in industrial systems, such as ventilation networks, diesel generator exhausts, and HVAC equipment, represents a critical challenge in acoustic engineering. Silencers equipped with perforated pipes and fibrous absorptive layers are widely employed due to their effective sound attenuation across a broad frequency range. In this research, the efficacy of the Transfer Matrix Method (TMM) in predicting the acoustic performance of three silencer types—namely, simple reactive, perforated reactive, and fibrous dissipative silencers—is investigated. During the modeling process, the impedance of the perforated pipes and the equivalent properties of the porous media were calculated using validated empirical formulations. The results were compared with experimental data, demonstrating that the TMM accurately predicts the transmission loss at frequencies below the cut-off frequency. At higher frequencies, discrepancies increase due to the violation of the plane-wave assumption and the inherent limitations of the empirical models. This study indicates that, despite its limitations above the cut-off frequency, the TMM remains a highly efficient tool for the preliminary design and optimization of industrial silencers, owing to its computational simplicity, speed, and satisfactory accuracy within the operational frequency range.
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Articles in Press, Accepted Manuscript
Available Online from 19 October 2026