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Noise pollution has become one of the major environmental concerns in present era. With the ever tightening laws and increasingly straight regulations for controlling noise pollution of automotive vehicles, mufflers are important part of engine system and commonly used in exhaust system to minimize noise caused by exhaust gases. Design of mufflers is a complex function that affects the noise characteristics and fuel efficiency of the vehicle. Traditionally, muffler design has been an iterative process by trial and error method. However theories and science that has undergone development in recent years has given a way for an engineer to cut short number of iterations. In today's competitive world market, it is important for a company to shorten product development cycle time and thereby cost. The objective of this paper is to propose a practical approach to design, develop and validate muffler practically which will give advantage over conventional method.

Recently quietness has become an important quality parameter for automotive vehicles and as a result various improvements have been brought to reduce noise at system and vehicle level. Due to stringent noise emission norms on automotive vehicles and increasing desire of quieter in-cab performance by users, reduction of air intake noise tends to be an area of explanation. Air intake noise, which was relatively considered as a minor source of noise in the past, is now gaining importance. To reduce air intake noise basically resonator and expansion chamber are used on automotive vehicles. Resonators are widely used for noise reduction of intake and exhaust systems, but due to increased number of components, its associated cost; complexity of the system increases. The next option that is an expansion chamber prevents the formation of large amplitude standing waves and dissipates sound energy, however use of such a device reduces engine torque at narrow range of engine speeds.

Exhaust noise from engines is one of component noise pollution to the environment. Exhaust systems are developed to attenuate noise meeting required db (a) levels and sound quality, emissions based on environment norms. Hence this has become an important area of research and development. Most of the advances in theory of acoustic filters and exhaust mufflers have been developed in last two decades. Mufflers are important part of engine system and commonly used in exhaust system to minimize sound transmissions caused by exhaust gases. Design of mufflers is a complex function that affects noise characteristics, emission and fuel efficiency of engine. Therefore muffler design becomes more and more important for noise reduction. Traditionally, muffler design has been an iterative process by trial and error. However, the theories and science that has undergone development in recent years has given a way for an engineer to cut short number of iteration.