This paper presents a CFD model of reverse-flow extended-tube muffler which is analyzed by a set of experimental tests, in order to acquire the relations between the structure and its corresponding pressure loss; a lot of research have been done through the numeric simulation. For the specific model, the distance from inlet pipe’s rear to the end cap has a large impact on the pressure loss, fur...

Standards have limited the allowable noise levels in different situations, requiring the study of solutions at the source, in the path or the receiver. Muffler is the major factor influencing the noise of rotary compressor. Control and analyze the acoustic characteristics of muffler is essential. Porous materials have been studied and widely applied to reduce aircraft and vehicular noise or ind...

background: noise is one of the most important harmful agents in work environment. noise pollution in oil refinery industries is related to workers' health. this study aimed to determine the overall noise pollution of an oil refinery operation and its frequency analysis to determine the control plan for a vent noise in these industries. methods: this experimental study performed in control unit...

For an engine running at a constant speed (RPM), the exhaust process and intake process are periodic. This enables use of the frequency-domain analysis of the essentially linear exhaust system consisting of the exhaust runners, manifold, exhaust pipe, the muffler proper and the tail pipe. Over the last forty years, transfer matrices have been derived for use with aeroacoustic state variables as...

*Fellow of the International Institute of Acoustics and Vibration, Author for correspondence: Email address: [email protected] 1 Three-Dimensional Acoustic Analysis of an Elliptical Chamber Muffler with a Side Inlet and a Side Outlet A. Mimani and M.L. Munjal* Facility for Research in Technical Acoustics (FRITA), Department of Mechanical Engineering, Indian Institute of Science, Ba...

Transmission loss and noise reduction of reactive mufflers are determined by linear acoustic theory and unsteady flow field study, respectively. The effects of extending the inlet tube of the muffler, adding holes to the extension, and the number of holes on both transmission loss and noise reduction are investigated. In noise reduction analysis, the Navier-Stokes equations and k-ε model are us...