Nalawade, R., "Analysis of Types of Mufflers and a New Approach Using Resonating Chamber," SAE Technical Paper 2017-28-1942, 2017.
The exhaust system of a vehicle is an integral part as it is responsible for reducing the noise of the exhaust gases and controlling the emissions as well. Mufflers are particularly the sub part of an exhaust system that reduce the sound level. Their geometry and size are meticulously calculated and decided so as to increase destructive interference of sound waves and their absorption by sound absorbent material packed around it. There are five types of basic mufflers which will be compared for their transmission losses. For this analysis of transmission losses, a software called Ricardo Wave Build has been used. Transmission loss is basically, the difference between the energy of the incoming charge and the energy of the outgoing charge of gases. So, more is the transmission loss, more efficient and productive is the muffler. Based upon the transmission loss characteristics, the mufflers are paired with their corresponding applications. Along with this, the concept of a resonating column is discussed. This is basically a chamber which helps in reducing sound by destructive interference and also promotes scavenging effect. The installation and its effect on transmission loss characteristics are observed. The feasibility and scope of the resonating chamber are further seen. It is seen that the resonating chamber gives positive results and is comparatively a simple addition to the muffler component of the exhaust system. All the types of mufflers are then combined with the resonating chamber and a table is constructed, comparing the transmission losses of all the mufflers depicted earlier.