# Efficient Modelling of Acoustic Metamaterials for the Performance Enhancement of an Automotive Silencer

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## Abstract

**:**

## 1. Introduction

## 2. Modular Silencer Design

## 3. Analytical Model

**M**is diagonal with elements $m\{1/2,1,1,\dots \}$,

**C**which is frequency dependent is also diagonal with elements $\{{\eta}^{\prime},\eta ,\eta ,\dots \}$ and the stiffness matrix $\mathbf{K}$ is tri-diagonal of the form

## 4. Performance Validation

## 5. Silencer Model

## 6. Experimental Silencer Performance

## 7. Conclusions

## Author Contributions

## Funding

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

## References

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**MDPI and ACS Style**

Deery, D.; Flanagan, L.; O’Brien, G.; Rice, H.J.; Kennedy, J. Efficient Modelling of Acoustic Metamaterials for the Performance Enhancement of an Automotive Silencer. *Acoustics* **2022**, *4*, 329-344.
https://doi.org/10.3390/acoustics4020020

**AMA Style**

Deery D, Flanagan L, O’Brien G, Rice HJ, Kennedy J. Efficient Modelling of Acoustic Metamaterials for the Performance Enhancement of an Automotive Silencer. *Acoustics*. 2022; 4(2):329-344.
https://doi.org/10.3390/acoustics4020020

**Chicago/Turabian Style**

Deery, Daniel, Lara Flanagan, Gordon O’Brien, Henry J. Rice, and John Kennedy. 2022. "Efficient Modelling of Acoustic Metamaterials for the Performance Enhancement of an Automotive Silencer" *Acoustics* 4, no. 2: 329-344.
https://doi.org/10.3390/acoustics4020020