Development of Transmission Loss Bench for Mufflers Based on the Transfer Matrix Method

2016 ◽  
Author(s):  
Yuri Fernandes dos Santos ◽  
Marcio da Silva Moura ◽  
Jeovano de Jesus Alves de Lima
Keyword(s):  
Transfer Matrix ◽  
Transfer Matrix Method ◽  
Matrix Method ◽  
Transmission Loss

Acoustic performance and flow analysis of a multi-chamber perforated resonator for the intake system of a turbocharged engine

2016 ◽  
Vol 231 (1) ◽  
pp. 120-129 ◽  
Author(s):  
Rong Guo ◽  
Wen-bo Tang ◽  
Wei-wei Zhu
Keyword(s):  
Pressure Drop ◽  
Transfer Matrix ◽  
Transfer Matrix Method ◽  
Matrix Method ◽  
Transmission Loss ◽  
Noise Spectrum ◽  
Broadband Noise ◽  
Test Facility ◽  
Acoustic Performance ◽  
Intake System

A multi-chamber perforated resonator is a type of silencer which can attenuate broadband noise. In order to address the noise issues originating from the intake system of a turbocharged engine, measurement tests are carried out to characterize the range and the amplitudes of the noise frequencies. A transfer matrix method and a non-linear least-squares optimization algorithm are combined in order to design the multi-chamber perforated resonator. A transmission loss test facility is designed on the basis of the two-load method so as to validate the acoustic performance of the resonator. Despite the difference between the amplitude of the transmission loss from the tests and the amplitude of the transmission loss obtained by the transfer matrix method, the shapes of the two curves have the same trend, and the measured transmission loss can meet the design target in the frequency range of interest. From the comparison between the intake noise spectrum with the resonator and the intake noise spectrum without the resonator, it can be seen that this resonator can efficiently attenuate the broadband intake noise of the engine. Also, a computational fluid dynamics flow simulation analysis of the intake system with the resonator is made so that its flow characteristics can be studied. The simulation results show that the air pressure drop of this resonator is slightly higher than that of the straight pipes but is still relatively low. It is also noted that the diameter and the curvature of the pipes have a great influence on the air velocity as well as on the pressure drop.

On Theoretical of Transmission Loss in Exhaust Muffler System

2013 ◽  
Vol 647 ◽  
pp. 848-853 ◽  
Author(s):  
Hanida Abdullah ◽  
Aminudin bin Abu ◽  
Pauziah Binti Muhamad ◽  
Asnizah Sahekhaini ◽  
Lee Kee Quen
Keyword(s):  
Numerical Analysis ◽  
Computer Program ◽  
Internal Combustion Engine ◽  
Transfer Matrix ◽  
Transfer Matrix Method ◽  
Matrix Method ◽  
Transmission Loss ◽  
Combustion Engine ◽  
Sectional Area ◽  
Cross Sectional

Exhaust muffler system iscommonly used to reduce noise associated with internal combustion engine exhausts.This paper presents a numerical analysis of transmission loss for exhaust muffler by using transfer matrix method. The objective of this study is to develop the computer program to predict the transmission loss of muffler.The influence of cross sectional area of pipe, effect of muffler length and temperature towards the transmission loss of muffler is discussed as well in present study. The efficiency and capabilities of the computing transmission loss is compared to the experiment results obtained from the previous established research paper.

scholarly journals Exhaust System Muffler Volume Optimization of Light Commercial passenger Car Using Transfer Matrix Method

2019 ◽  
Vol 4 (1) ◽  
pp. 132-138
Author(s):  
Barhm Mohamad ◽  
Károly Jalics ◽  
Milad Kermani
Keyword(s):  
Transfer Matrix ◽  
Weight Reduction ◽  
Transfer Matrix Method ◽  
Matrix Method ◽  
Transmission Loss ◽  
Exhaust System ◽  
Design Tool ◽  
Size Reduction ◽  
Observation Data ◽  
Pipe Length

Nowadays, the automotive industry is focused on weight and size reduction. Main advantage of this weight and size reduction are improving the fuel economy. The specific fuel consumption of a vehicle can be improved through e.g. downsizing area of heat loss, if we focus on vehicle with weight reduction. Weight reduction can be done by replacing material or by changing the size (dimensions) of components. In the present work we have focused on Audi A6 muffler, troubleshooting and optimizing the muffler by changing pipe length of inlet and outlet, also by replacing the original mesh plate to porous pipe. Based on optimization, prototype has been built with the help of 3D design tool CATIA V5 and the calculations of transmission loss (TL) have been performed by MATLAB. Plane wave-based models such as the transfer matrix method (TMM) can offer fast initial prototype solutions for muffler designers. The principles of TMM for predicting the transmission loss of a muffler was used. Result of this present study of an existing muffler has been analysed and then compared with vehicle level test observation data. Noise level have been optimized for new muffler design. Other literatures were played significant rule for validate our results.

Analysis of Baffle Effect for Measuring Transmission Loss

2015 ◽  
Vol 752-753 ◽  
pp. 1263-1268
Author(s):  
Hanida Abdullah ◽  
Aminudin Abu ◽  
Pauziah Muhamad ◽  
Asnizah Sahekhaini ◽  
Lee Kee Quen
Keyword(s):  
Transfer Matrix ◽  
Excellent Agreement ◽  
Transfer Matrix Method ◽  
Matrix Method ◽  
Transmission Loss ◽  
Source Code ◽  
Noise Pollution ◽  
Research Paper ◽  
Exhaust Gases ◽  
Exhaust Noise

Exhaust noise is one of the noise pollution to the environment and it will cause interference that may harm the activity or balance of human. A muffler is designed to minimize transmission caused by exhaust gases. In this paper, the principle of transfer matrix method is used to analyze the transmission loss. The method is used for developed source code programming to predict muffler performance. The result from programming show excellent agreement with the previous established research paper. This programming is applied for baffle effect to determine transmission loss.

scholarly journals Effects of Parameters of Helmholtz Resonator on Transmission Loss of Hybrid Muffler

2018 ◽  
Vol 7 (3.17) ◽  
pp. 151
Author(s):  
Thiha Zaw ◽  
Aminudin Abu ◽  
Noor Fawazi ◽  
A M. Wahab
Keyword(s):  
Transfer Matrix ◽  
Transfer Matrix Method ◽  
Matrix Method ◽  
Transmission Loss ◽  
Helmholtz Resonator ◽  
Transmission Losses ◽  
Expansion Chamber ◽  
Low Frequencies ◽  
Helmholtz Resonators ◽  
Resonator Cavity

Expansion chamber and Helmholtz resonators are widely used in noise control. In this paper, they are combined to use as a hybrid muffler. The analysis is done to investigate the influence of the parameters of Helmholtz resonator on transmission loss. The transfer matrix method is used in the analysis. The result of transmission loss from the transfer matrix method is validated with the result from experimental two-load method using four microphones impedance tube. After had the transmission loss of the hybrid muffler been validated, the study was proceeded to investigate the effects of parameters of Helmholtz resonator on the transmission loss. The root mean square value of transmission loss were also calculated to compare the transmission losses clearly. In this paper, we investigated the effect of length of the neck of Helmholtz resonator, the effect of diameter of the neck of Helmholtz resonator, the effect of the length of the Helmholtz resonator cavity and the effect of the diameter of the Helmholtz resonator cavity for stationary medium. It is found that the transmission loss is increased when the diameter of the neck of Helmholtz resonator is increased. When the length of the neck is reduced, the transmission loss is increased. The transmission loss can also be increased by reducing the diameter of resonator cavity. It is better to increase the transmission loss at low frequencies by increasing the length of the resonator cavity.  

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