Design and Development of an Exhaust Muffler With Improved Transmission Loss for a Naturally Aspirated Diesel Engine 2019-28-0046
Exhaust noise from engines is one of component noise pollution to the environment. Significantly, the exhaust noise in terms of pressure is about 10 times all the other noises (structural noise) combined. 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.
The purpose of this experiment was to conduct design, analyse and test the exhaust muffler in order to determine the pressure drop and noise reduction in the exhaust system. For this analysis, ANSYS Fluent was used. From the calculations Muffler diameter and length were selected whereas perforations and baffles were considered so as to have maximum pressure drop and noise reduction. In this study, a reactive perforated muffler is investigated. several designs were considered for maximum pressure drop and the best was selected for manufacturing. Further the validation was done on a muffler in which the inlet pressure was under the simulated results but the experimental outlet pressure was beyond the simulated results. The backpressure was less due to excess of air passage inside the muffler. The muffler was then experimented for noise level and it has shown a decrease in maximum 13% of the noise .