Topic
Muffler
About: Muffler is a research topic. Over the lifetime, 8209 publications have been published within this topic receiving 42664 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this paper, the potential for waste energy recovery from exhaust gases in a diesel passenger car mounted in a chassis dynamometer was investigated under three temperature conditions, and exergy analysis was included to find the potential of exhaust gases to produce useful work at six points in the exhaust system.
75 citations
TL;DR: The multidomain boundary element technique is used for the analysis of muffler problems in which the acoustic region consists of thin obstacles, such as extended inlet or outlet tubes and internal connecting tubes as mentioned in this paper.
74 citations
TL;DR: In this paper, an expression for attenuation (insertion loss) of a muffler has been proposed in terms of convective terminal impedances and a velocity ratio, on the lines of the one existing for acoustic filters.
74 citations
TL;DR: In this article, a first and second noise suppressing mechanism are provided inside the muffler, each mechanism is provided with a discharge pipe for discharging exhaust gas to outside the exhaust manifold.
Abstract: A first and second noise suppressing mechanism are provided inside the muffler. Each mechanism is provided with a discharge pipe for discharging exhaust gas to outside the muffler. The first noise suppressing mechanism reduces exhaust noise in the low engine speed region. The second noise suppressing mechanism reduces noise in the medium and high engine speed regions. A valve is provided that connects the first noise suppressing mechanism and second noise suppressing mechanism according to the engine exhaust pressure. In the low speed region, the valve is closed and exhaust gas is discharged via the first noise suppressing mechanism where mainly low frequency noise is eliminated. In the medium and high speed regions, the valve is opened and exhaust gas is also discharged via the second noise suppressing mechanism where high frequency noise specific in these regions is also eliminated. Further, by the increased exhaust cross-sectional area, power drop due to increase of back pressure in the muffler in the high speed region, is prevented.
71 citations
TL;DR: In this paper, a wind tunnel designed specifically for aerodynamic noise research has been constructed for the purpose of measuring the noise radiated by the relatively weak noise source of an isolated airfoil placed in a uniform, low turbulence stream.
Abstract: This new wind tunnel, designed specifically for aerodynamic noise research, has a variable area, open jet test section enclosed in an anechoic chamber. Speeds up to a Mach number of 0.65 are possible with a test section area of 5 ft2. A separate, low noise level, high pressure air source is provided for jet noise studies. Design and construction considerations for the major tunnel sections (i.e., inlet, anechoic chamber, diffuser, muffler, driver) are described. Aerodynamic and acoustic calibration of the tunnel is discussed in relation to design criteria. Problems applicable to other acoustic tunnels such as background noise, edge tone suppression, deflected jet noise and distortion of noise directivity patterns by shear layer refraction are discussed. Initial testing demonstrated that a sufficiently low background noise level has been obtained to permit measurement of the noise radiated by the relatively weak noise source of an isolated airfoil placed in a uniform, low turbulence stream.
70 citations