This study was conducted to investigate the effects of engine operating conditions and exhaust aftertreatments on the mutagenicity of diesel particulate matter (DPM) collected directly in an underground mine environment. A number of after-treatment devices are currently used on diesel engines in mines, but it is critical to determine whether reductions in DPM concentrations result in a correspo...

Research on new techniques of single-chamber mufflers hybridized with an internal extended tube has been addressed; however, the research work on a space-constrained multi-chamber muffler hybridized with multiple internal extended tubes which may increase the acoustical performance within a specified back pressure has been ignored. Therefore, the analysis of a sound transmission loss (STL) for ...

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...

Nowadays, creating an environmentally reliable car by reducing the volume of harmful gases in it is a global problem mankind. For this reason, one main areas research to improve exhaust gas cleaning system internal combustion engines. However, date, there are no universal designs that would performance purification system. In regard, development new vehicle based on effective method urgent task...

*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...