Volume 17, Issue 1 (Occupational Medicine Quarterly Journal 2025)                   tkj 2025, 17(1): 1-11 | Back to browse issues page

Ethics code: IR.IUMS.REC.1399.931


XML Persian Abstract Print


Download citation:
BibTeX | RIS | EndNote | Medlars | ProCite | Reference Manager | RefWorks
Send citation to:

Alimohammadi I, Farrokhi M, Javadi S, Nasher S. Examining the role of the hole and the orientation of the baffle on the loss of sound transmission in reactive mufflers using COMSOL software simulation. tkj 2025; 17 (1) :1-11
URL: http://tkj.ssu.ac.ir/article-1-1344-en.html
, farokhi1.ma@gmail.com
Abstract:   (30 Views)

Abstract
Introduction: Nowadays, noise pollution in the environment has become as a worldwide health concern. A  large share of this noise comes from vehicles, where mufflers in their exhaust systems are essential for lowering engine noise levels. Proper muffler design and modifications to its geometric parameters,  including adding holes in the baffle and changing their orientation, can significantly influence the acoustic performance of mufflers and contribute  effective in enhanced noise reduction.
Materials and Methods: The finite element numerical method was utilized to examine the acoustic effectiveness of the analyzed mufflers.  At first, the mufflers were designed and modeled using COMSOL software. Subsequently, by modifying the desired geometric parameters, specifically by adding perforations to the baffle and changing the baffle orientations, their effect on sound transmission loss was examined.
Results: The results of this study indicated that the sound transmission loss across the examined frequency range did not exhibit a consistent pattern with changes in geometric parameters. Specifically, at certain frequencies, the changes led to an increase in sound transmission loss, whereas at others, they resulted a decrease. However, in general, positioning the baffle's apex towards the muffler outlet increased the average transmission loss, while orienting the baffles’s peak towards the muffler outlet enhanced the average transmission loss, whereas adding  perforations to the baffle reduced the average transmission loss.
Conclusion: Creating perforations on the baffle and changing its orientation in reactive mufflers can affect sound transmission loss and, more broadly, its acoustic performance.

Full-Text [PDF 1196 kb]   (11 Downloads) |   |   Full-Text (HTML)  (6 Views)  
Type of Study: Research | Subject: Physical agents
Received: 2024/11/19 | Accepted: 2025/03/30 | Published: 2025/03/30

Add your comments about this article : Your username or Email:
CAPTCHA

Send email to the article author


Rights and permissions
Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

© 2025 CC BY-NC 4.0 | Occupational Medicine Quarterly Journal

Designed & Developed by : Yektaweb