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Open Access Original Research

Analysis of Sound Transmission Loss in Hybrid Mufflers for Automotive Applications

by 
   Ravi Jatola,    Amit Kumar Guptab,
Volume :   | Issue :   | Received :  January 6, 2024 | Accepted :  March 10, 2024 | Published :  May 4, 2024

Keywords

1-D analysis, Acoustics, Muffler, Sound Transmission Loss, Wave 1-D,

Abstract

An exhaust system’s noise level can be reduced with the use of a muffler. There is general recognition that baffled exhaust mufflers reduce noise emissions and increase the loss of sound transmission. The reduction of sound transmission can be further achieved by inserting sound-absorbing materials inside the muffler. Exhaust muffler systems with strategically positioned baffles have been shown to effectively reduce noise emissions, thereby improving acoustic performance. Baffles divert and disrupt sound waves, reducing the amount of unwanted noise that is transmitted and fostering a more peaceful and controlled acoustic environment. Sound-absorbing materials being included into mufflers is a major advancement in noise reduction technology. The current research purpose is to explore the changes in internal design of muffler with control volume influence towards the acoustic sound transmission loss. The design parameters were altered with constant volume and their variation was evaluated. In this work, by changing the number and position of the baffle, perforation percentage in the central and in outlet pipe. It has been seen that what is the difference in the sound transmission loss and finally, the sound transmission loss has been measured by filling the sound absorbing material into the constant volume muffler and observed how much the sound transmission loss has increased.

Full Text

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