Analysis of the changes impact in the construction of the vehicle exhaust silencer on the noise emission level (original) (raw)
Related papers
Effect of Variation in Build-Up Parameters on Noise Reduction in Automobile Engine Silencers
2012
The study focused on practical methods of reducing noise levels in automobile engine silencers. A comprehensive step to examine the flow pattern in relation to noise level generation, modify silencer parameters to effect noise level reduction is considered. The experimentation commenced with flow linearization process and this was followed by a design/build/test laboratory procedure to ascertain the minimum noise level achievable by varying the inlet pipe size, resonating chamber length and the orifice size of the geometric build up of the silencers. Results from experimentation shows a reduction in noise level to the tune of 13.2dB (A) when comparison is made with the initial noise level of silencer used as the baseline level at 76.9dB (A). The results was incorporated to generate an optimum model for the IC-engine (Volkswagen Passat Model) of 1921 cm 3 engine capacity used as the test engine during the experimentation. Noise level in dB (A) were depicted on noise level-time graph.
International Journal for Research in Applied Science & Engineering Technology (IJRASET), 2022
The ideal of this work is to develop a silencer that can amend dangerous exhaust discharge and noise produced in this conventional silencer. The health and hygienic policy depend upon the term air pollution. Weakened air causes physical illgoods and decides undesirable aesthetic and physiological goods. Air pollution can be defined as an inclusion to atmosphere of any material solid or gases which will have a various effect on life. The main adulterants contribute by machines are unburned hydrocarbon (UBHC), oxides of nitrogen (NOx), carbon monoxide (CO), and Lead. This research work is an attempt and contribution in this direction; it's substantially dealing with the comb of emission and noise. This system is fitted to the exhaust pipe of the machine. This type of silencer is used to reduce emission, and Noise and also reduces its dangerous goods with the help of actuated outland, lime water. As the Sound produced under lime water is less audible than it produced in the atmosphere. This is because of small sprockets which are present in water motes, which lower their breadth and lower the sound position. Hence water is used in this silencer. These silencers are used to reduce the noise and control the emissions of dangerous feasts and release much lower weakened feasts to the terrain and it's easy to install.
Design, Development and Fabrication of Automobile Silencer for Exhaust Flow
International Journal of Scientific Research in Science, Engineering and Technology, 2019
Air pollution is most important from the public health point of view, because every individual person breathes approximately 22000 times a day, inhaling about 15 to 22 Kg of air daily. Polluted air causes physical ill effect decides undesirable aesthetic and physiological effects. Air pollution can be defined as addition to our atmosphere of any material, which will have a dexterous effect on life upon our planet. The main pollutants contribute by automobiles are carbon monoxide (CO), unburned hydrocarbon (UBHC), oxides of nitrogen (NOx) and Lead. Automobiles are not the only source of air pollution, other sources such as electric power generating stations, industrial and domestic fuel consumption, refuse burning, industrial processing etc. also contribute heavily to contamination of our environment so it is imperative that serious attempts should be made to conserve earth’s environment from degradation. An aqua silencer is an attempt in this direction, it is mainly dealing with control of emission and noise. An aqua silencer is fitted to the exhaust pipe of engine. Sound produced under water is less hearable than it produced in atmosphere. This mainly because of small sprockets in water molecules, which lowers its amplitude thus, lowers the sound level. Because of this property water is used in this silencer and hence its name AQUA SILENCER. The noise and smoke level is considerable less than the conventional silencer, it is cheaper, no need of catalytic converter and easy to install.
Muffler Design for Automotive Exhaust Noise Attenuation -A Review
In these review paper different types of mufflers and design of exhaust system belonging engine has been studied. The object of this study is decide muffler design which one reduces a large amount of noise level and back pressure of engine. In designing, there is different parameter which has to taken in to the consideration. These parameters affect the muffler efficiency.
2021
The single cylinder water cooled diesel engine is used for various applications such as in agriculture as well as in domestic purpose. This diesel engine having too much noise level; this is irritating not only for operator but also for external environment. High noise level is harmful for human beings. For the reduction of noise level ‘silencer’ is mounted on this diesel engine, which attenuates the noise. The noise level of this water cooled single cylinder diesel engine can be reduced further by modifying its design. This review is conducted to study the variety methods used by various researchers for noise reduction of silencer through modification of its existing shape. In this study the recent developments on design modification of silencer for diesel engine exhaust manifold, their performance evaluation using various methods such as computational fluid dynamics (CFD), acoustic software, various geometrical types of exhaust manifold and their impact on the diesel engine perfor...
A Review on Muffler Design for Exhaust Noise Attenuation
International Journal of Engineering and Technology (IJET) , 2017
The pressure waves escape from the engine exhaust with a high velocity producing an offensive exhaust noise. A properly designed exhaust silencer is helpful to reduce exhaust noise. In these review paper different types of mufflers and a performance characteristic of muffler have been studied. In designing, different parameter which has been to taken into the consideration. These parameters affect the muffler efficiency. This paper also focuses on sound attenuation, back pressure which is most important criteria for selection of muffler.
2000
In this contribution a sound quality investigation concerning automotive exhaust noise is presented. The investigation deals with the disturbing elements of exhaust noise (e.g. booming noise, hollow sound, whistle,...). The investigation consists of three parts. The first part consists in determining a definition for each disturbing element (establish a sound quality catalogue). The next step is to establish a metric for each defined element. The final step is then to find the link between the established metrics and the geometry of the exhaust system. This is a difficult step due to the large number of components (tubes, baffles, perforations,...). The exhaust noise is also influenced by the flow-induced noise. This paper focuses on determining the link between the metrics and the exhaust system's geometry. For the disturbing element whistle the link between metric and geometry is discussed in detail. For the covering abstract see ITRD E107776.
Development of an active exhaust silencer for internal combustions engines
Proceedings of the International Conference on Noise and Vibration Engineering, 1998
A silencer to attenuate engine exhaust noise using active control methods is developed. The device consists of an electrically driven valve, combined with a buffer volume, which is connected to the exhaust outlet. Using the mean flow through the valve and the pressure fluctuations in the volume, the valve regulates the flow in such a way that only the mean flow passes through the exhaust outlet. The fluctuations of the flow are temporally buffered in the volume. To carry out optimization and validation experiments, a cold engine simulator is developed. This device generates realistic exhaust noise and the matching gas flow using compressed air. The simulator allows quick and reliable acoustic and fluid dynamic experiments on exhaust prototypes. The active silencer is capable to reduce the exhaust noise from 91 dBA to 78 dBA after the tail pipe outlet, with a back pressure of 3 kPa to the engine.
EVALUATION OF DESIGN ALTERNATIVES FOR AUTOMOBILE SILENCER WHILE ADDRESSING COMPLIANCE TO THE GENERIC NORMS FOR VIBRATION Balraj .D.Kawade1, Niranjan D. Khaire2, Swapnil.S.Kulkarni3 1Student, 2Professor, Department of Mechanical Engineering, Rajarshi Shahu College of Engineering Pune, India 3Director, Able Technologies (I) Pvt. Ltd., Pune, India ABSTRACT In automobiles exhaust system is of great importance and silencer is used to minimize unwanted noise, the exhaust gas of high pressure and high temperature coming out of internal combustion engine leads to undesirable noise is known as noise pollution. Pollution creates more disturbance in the environment. Noise is measured in decibel. Audible waves are of frequency ranges from 20 Hz to 20000 Hz. To minimize sound frequency mufflers are used in silencer assembly. The exhaust gases coming out from engine are at very high speed and temperature. Silencer has to reduce noise, vibrations. While doing so it is subjected to thermal, vibration and fatigue failures which cause cracks. So it is necessary to analyze the .Vibrations which would further help to pursue future projects to minimize cracks, improving life and efficiency of silencer. Many researchers have studied and postulate behavior of silencer under loading and studied modal analysis with context to vibrations. Here we can study the given case and avoid resonance if any and look for safe design of silencer by modal analysis. KEYWORDS: Finite element method, silencer, muffler, resonance, vibrations, modal analysis, Radioss, hypermsh.