3-D acoustic analysis of elliptical chamber mufflers having an end-inlet and a side-outlet: An impedance matrix approach

Mimani, A.; Munjal, ML

doi:10.1016/j.wavemoti.2011.11.001

Cited by 36 publications

(13 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although it can achieve a suppression effect in the low-frequency range, its effective silencing band is always too narrow [4,[18][19][20]. In contrast, the expansion-type silencer can achieve a broadband character of noise reduction, yet its silencing frequency is often too high [21,22].…”

Section: Introductionmentioning

confidence: 99%

Transmission of Low-Frequency Acoustic Waves in Seawater Piping Systems with Periodical and Adjustable Helmholtz Resonator

Liu

Yang

2017

JMSE

View full text Add to dashboard Cite

Abstract:The characteristics of acoustic wave transmitting in a metamaterial-type seawater piping system are studied. The metamaterial pipe, which consists of a uniform pipe with air-water chamber Helmholtz resonators (HRs) mounted periodically along its axial direction, could generate a wide band gap in the low-frequency range, rendering the propagation of low-frequency acoustic waves in the piping system dampened spatially. Increasing the air volume in the Helmholtz chamber would result in a sharply decrease in the central frequency of the resonant gap and an extension in the bandwidth in the beginning, yet very slowly as the air volume is further augmented. Acoustic waves will experience a small amount of energy loss if the acoustic-structure interaction effect is considered. Also, the structure-borne sound will be induced because of the interaction effects. High pressure loadings on the system may bring in a shrink in the band gap; nevertheless, the features of broad band gaps of the system is still be maintained.

show abstract

Section: Introductionmentioning

confidence: 99%

Transmission of Low-Frequency Acoustic Waves in Seawater Piping Systems with Periodical and Adjustable Helmholtz Resonator

Liu

Yang

2017

JMSE

View full text Add to dashboard Cite

show abstract

“…Many scholars, including Oh and Lee (2015), have studied possible solutions from different perspectives. Tian and Su (1998) proposed the sensitivity analysis method to optimize the noise elimination performance of the muffler and verified the improvement effect; Zuo et al (2014) analyzed the influences on the acoustic characteristics by the position and numbers in the diaphragm of the micro-perforated pipe muffler; Guo et al (2011) concluded that it should be appropriate to choose the pore of purifying material and select larger diameters in the initial muffler design; Pan et al (2011) proposed the direct mixed boundary element method to transform and build models on porous absorption material and showed that it is well matched with the experimental data; Kornatsu (2008) predicted the acoustic characteristics of fiber absorption materials by building new mathematical models; Yasuda et al (2010, 2013) studied the frequency and attenuation characteristics of the muffler; Montenegro et al (2013a, b) predicted the transmission loss of the muffler with absorption materials by the quasi-3D non-linear method and proved the practicability by comparing the experimental data; Mimani and Munjal (2012) studied the effects on acoustic performance by the angle, axial position and length of the inlet and outlet pipes of the elliptic cavity muffler; Desantes et al (2012) and Antebas et al (2013) studied the derived relations of unsteady flow in the porous wall and the determination of boundary conditions and predicted the inhomogeneous acoustic characteristics of multiple perforation dissipative muffler; Barbieri and Barbieri (2012, 2013) optimized the acoustic cavity geometry of the muffler based on finite element method and genetic algorithm and Chazot et al (2013) used the partition of unity finite element method to solve the shortwave Helmholtz problem of a two-cavity muffler with absorption material and proved its validity.…”

Section: Introductionmentioning

confidence: 84%

Performance study of the exhaust purification muffler of a diesel engine

Wei

et al. 2016

MMMS

View full text Add to dashboard Cite

Purpose The purpose of this paper is to present experimental studies on the designed muffler which contains ceramic foam and has the integration function of purification and noise elimination. Design/methodology/approach Comparative tests were done on a diesel engine with no muffler, the original muffler and the purification muffler. The soot index (light absorption coefficient), A-weighted sound pressure level and fuel consumption rate, which were collected by the partial flow opacity method, the insertion loss measurement of spatial five points and the load characteristics tests, respectively, and the effects of purification and noise elimination were studied. Findings The results of this paper state that the purification muffler shows great improvement on exhaust soot purification and noise elimination. The variation in diesel fuel consumption rate was small, the sound pressure level of purification muffler was reduced by 6 to 10 dB, the insertion loss of the purification muffler was increased by 6.41 dB and the average light absorption coefficient decreased by 57.8 percent compared with the original muffler. Originality/value The value of this study is that it supplies a purification muffler which contains a ceramic foam. Under the prerequisite of little effect on the fuel economy of diesel engine, the purification muffler shows great improvement in exhaust soot purification and noise elimination.

show abstract

“…A.Mimani, M.L.Munjal [1] have discussed the acoustical behavior of an elliptical chamber muffler having an end-inlet and side-Outlet port is analyzed semi-analytically. The acoustic performance of these configurations is evaluated in terms of transmission loss (TL).…”

Section: Literature Reviewmentioning

confidence: 99%

Optimization and Experimental Validation of Elliptical Reactive Muffler with Central Inlet Central Outlet

Wankhade¹,

Bhattu²

2015

IJERT

View full text Add to dashboard Cite

Exhaust noise from engines is one of component noise pollution to the environment. 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. Mufflers are important part of engine system and commonly used in exhaust system to minimize sound transmissions caused by exhaust gases. Design of mufflers is a complex function that affects noise characteristics, emission and fuel efficiency of engine. Therefore muffler design becomes more and more important for noise reduction. The objective of the paper is to propose a simple in construction, effective silencing device, which can achieve good results in minimizing the noise. The acoustic analysis is one of the methods which help to analyses the sound level at the tail pipe. This optimization revises acoustic analysis of muffler using Finite Element Analysis. The muffler is modeled in 'PRO E Wildfire 5.0 and 'COMSOL MULTIPHYSICS' is used for acoustic analysis. Effect of extrusion of inlet and outlet pipe inside the chamber and also the position of the extra inlet tube (i.e. divided inlet) to the chamber and then optimized this parameter to get the minimum sound pressure level (SPL) or maximum transmission loss (TL). The effect of SPL on the walls of the muffler is not considered. The material of the muffler is also not considered. This optimized model of elliptical muffler is manufacture and then validate with the experimental analysis.

show abstract

3-D acoustic analysis of elliptical chamber mufflers having an end-inlet and a side-outlet: An impedance matrix approach

Cited by 36 publications

References 24 publications

Transmission of Low-Frequency Acoustic Waves in Seawater Piping Systems with Periodical and Adjustable Helmholtz Resonator

Transmission of Low-Frequency Acoustic Waves in Seawater Piping Systems with Periodical and Adjustable Helmholtz Resonator

Performance study of the exhaust purification muffler of a diesel engine

Optimization and Experimental Validation of Elliptical Reactive Muffler with Central Inlet Central Outlet

Contact Info

Product

Resources

About