Enhancement on Sound Transmission Loss for Various Positioning of Inlet and Outlet Duct of the Muffler

Full Text (PDF, 953KB), PP.1-11

Views: 0 Downloads: 0

Author(s)

Amit Kumar Gupta 1,* Ashesh Tiwari 1

1. Mechanical Engineering Department, IET-Devi Ahilya University, Indore, INDIA

* Corresponding author.

DOI: https://doi.org/10.5815/ijem.2015.04.01

Received: 14 Aug. 2015 / Revised: 16 Sep. 2015 / Accepted: 21 Oct. 2015 / Published: 8 Nov. 2015

Index Terms

Transmission Loss (TL), Wave 1-D, Comsol, Inlet & Outlet Duct

Abstract

Muffler acts as noise reduction element on exhaust system. Noise from an automotive application is the major source of noise pollution. Here the transmission loss of central inlet and central outlet muffler of single expansion chamber has been compared and validated in three methods namely transfer matrix method, finite element analysis and an experimental method for this purpose an experimental setup has been built up which is based on two load method. Several researchers have worked in the area of noise attenuation on central inlet by changing the position of outlet as side outlet but no one emphasizes on offset of the central inlet and central outlet position. Thereafter the finite element analysis tool Ricardo wave 1-D and comsol multiphysics is used to evaluate transmission loss for various offset position of inlet and outlet duct of the muffler. The very purpose to improve the acoustic performance of central inlet with offset outlet pipe by measuring transmission loss of offset inlet with offset outlet with various positions by keeping same space. Finite element analysis shows that higher attenuation can be achieved by increasing offset distance of central inlet & outlet outlet towards radial direction of the expansion chamber with the variation of 0.2r, 0.4r and 0.6r. Here 'r' is radius of single expansion chamber. The result shows that high transmission loss can be achieved by increasing the offset radial distance of the inlet pipe and outlet pipe. Further higher attenuation can also be achieved in case of fixed the distance of offset inlet and outlet at 0.6r by rotating the offset outlet which is also offseted at 0.6r distance by 0o, 45o, 90o, 135o and 180o. On ward rotation from remaining 180o to 360o the behavior of wave propagation will be same what has been reflected between 0o to 180o. Transmission loss maximizes when the offset outlet is loacted at 90o. It clearly reveals that optimization can be achieved by using finite element analysis tool by using virtual protyping. 

Cite This Paper

Amit Kumar Gupta, Ashesh Tiwari,"Enhancement on Sound Transmission Loss for Various Positioning of Inlet and Outlet Duct of the Muffler", International Journal of Engineering and Manufacturing(IJEM), Vol.5, No.4, pp.1-11, 2015. DOI: 10.5815/ijem.2015.04.01

Reference

[1]M. L. Munjal, "Recent Advances in Muffler Acoustics", International Journal of Acoustics and Vibration, Vol. 18, No. 2, pp. 71-85,2013.

[2]A. K. Gupta, and A.Tiwari, "Measurement of Sound Transmission Loss on Straight and Zigzag Perforated Concentric Tube Muffler with Constant Porosity", International Journal on Emerging Technologies Vol.6, Issue 2, pp 35-40, 2015 . 

[3]R. Barbieri and N.Barbieri, "Finite element acoustic simulation based shape optimization of a muffler", applied acoustics, Volume 67, Issue 4, pp 346–357, 2006.

[4]L.J.Yeh, "Computer-aided optimal design of a single-chamber muffler with side inlet/outlet under space constraints", Journal of Marine Science and Technology, Vol. 11, Issue 4, pp. 189-196, 2003.

[5]A.K. Gupta and A. Tiwari "Comparison of Existing Experimental Results with Different Types of Simulation Software for Transmission Loss Estimation of Muffler", March 2015, Volume 2, Issue 1,Trends in Machine Design, pp 17-20, 2015.

[6]Min GUO, Chunhua JIA I.J., "Neural Network Recognizes Fruit Fly's Wing Vibration Sound Based on Hilbert-Huang Transform", I.J. Engineering and Manufacturing, Vol. 1, Issue 6, pp. 25-30, 2011.

[7]M.L.Munjal, Acoustics of Ducts and Muffler, Wiley, New York, 1987.

[8]A. Selamet, and Z.L. Ji, "Acoustic attenuation performance of circular expansion chambers with extended inlet/outlet", Journal of Sound and Vibration, 223, pp197-212, 1999. 

[9]R. Mohamed SabryAllam et. al., "Modelling and analysis of single expansion chamber using response surface methodology" international journal of mechanical and materials engineering vol.2 issue 1, 2012. 

[10]Z. Tao and A.F. Seybert, "A review of current techniques for measuring muffler transmission loss" SAE 2003.

[11]A.K.M. Muhiuddin, A. Rahman and Y.B. Gazali, "Simulation and experimental investigation of muffler performance" international journal of mechanical and materials engineering,Vol2,2007. 

[12]C.Y.R. Cheng, and A.F. Seybert, "A multi domain boundary element solution for silencer and muffler performance prediction", J. Sound and Vibration, pp 119-129, 1991. 

[13]S.N.Y Gerges et.al., "Muffler Modeling by Transfer Matrix Method and Experimental Verification", J. Braz. Soc. Mech. Sci.& Eng., vol. 27, no.2, pp.132-140, 2005.

[14]A.K. Gupta and A. Tiwari, "Modeling For Transmission Loss Prediction Of Different Shapes Of Acoustic Muffler With An Experimental Analysisʺ, Journal Of Experimental & Applied Mechanics, Vol 6, No 1, 2015.

[15]Bhattu A.P., Sahasrabudhe A.D. "Acoustic Performance of Reactive Central Inlet and Side Outlet Muffler by Analytical Approach", International Journal of Engineering and Innovative Technology, Volume 2, Issue 1, pp 44-49, 2012.

[16]A.K. Gupta and A. Tiwari, "Transfer Matrix Method for Noise Attenuation on Single Expansion Chamber Muffler having Central Inlet and Central Outlet with Experimental Techniques and FEA Validation", International Journal of Theoretical & Applied Sciences, Vol. 7, Issue 2, pp. 14-20, 2015.