Transmission and Insertion Loss in Commercial Mufflers Using Pink and White Noise Sources
Author : Archana Kale and Farhat Surve
Abstract :
The muffler is an essential component of an automobile, as it reduces noise by reducing the sound pressure level emanating from the engine, and hence reduces sound pollution. Commercial mufflers are generally reactive mufflers with an added absorptive element. The objective of our study is to compare the insertion loss across two different commercial mufflers, using pink and white noise sources, at constant input power values. The pink and white noise sources are derived from Radon Soft, V1.21. The SPL at the output port of the muffler is measured using a sound level meter. The response of two mufflers manufactured by Royal Enfield and fitted to their motorbikes viz. the Classic 350 Bullet (m=3.87) and the Thunderbird (m=4.29), is investigated for insertion loss, bandwidth, and dissipation. The experimentally obtained insertion loss is compared with the theoretical estimates of transmission loss for each of the models, and it is found that both TL and IL show similar results. The resonating length pays an important role in deciding all parameters.
Keywords :
Muffler, insertion loss, pink noise, noise pollution, noise reduction
