Analysis of Noise Level with Convergent and Divergent Shape of Muffler and its Impact on Noise Pollution

Abstract

Noise pollution is one of the key hazards that decreases people's quality of life globally. Due to the rapid development of technology, industrialization, urbanization, and transportation networks, noise pollution has reached serious levels in recent years. Sound transmission loss, the attenuation of sound as it passes through diverse objects and environments, is crucial in lowering noise pollution and preserving the acoustic integrity of ecosystems. Due to de-throttling tactics implemented to optimize cylinder fill, the intake system of internal combustion engines is the primary noise source while the vehicle is at low speeds and high loads. Therefore, achieving high acoustic performance of intake systems constitutes a critical issue in complying with the increasingly stringent European regulations for overall noise emission. The Transmission Loss computation is typically the most used technique for describing a system's acoustic performances. This work provided an overview of sound transmission loss and discussed its substantial environmental effects. It investigates the fundamentals of sound transmission, the factors that influence it, and the environmental impacts of sound attenuation. This paper proposed a comparison of three designs like straight duct (muffler), convergent and divergent design of muffler. The main aim is to observe sound transmission loss and compare the noise level with three muffler configurations with the same gas volume. High transmission loss indicates more noise reduction in muffler design, which will help reduce environmental noise pollution.