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Three-Dimensional Numerical Study on the Pulsating Flow Inside Automotive Muffler with Complicated Flow Path
Technical Paper
2001-01-0944
ISSN: 0148-7191, e-ISSN: 2688-3627
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Event:
SAE 2001 World Congress
Language:
English
Abstract
Exhaust system is composed of several parts. Among them, design of muffler system strongly influences on engine efficiency and noise reduction. Hence, thorough comprehension of flow characteristics inside muffler is necessary. In this study, three-dimensional steady and unsteady compressible flow analysis was performed to understand the flow characteristics, pressure loss and amplitude variation of pulsating pressure. The computational grid generation was carried out. And the three-dimensional fluid motion inside the muffler was analyzed by STAR-CD, the computational fluid dynamics code. RNG k- ε turbulence model was applied to consider the complexity of the geometry and fluid motion. The steady and unsteady flow field inside muffler such as velocity distribution, pulsating pressure and pressure loss was examined. In case of unsteady state analysis, velocity of inlet region was converted from measured pulsating pressure. Experimental measurement of pressure and temperature was carried out to provide the boundary and initial condition for computational study under the engine operating conditions. Computational results show that the pressure drop is derived from the sudden reduction and the sudden expansion effect of the baffle plates, located in the middle of chamber, and heavily depends on the variation of the flow direction. It is also found in good agreement within 6% of the measured values.
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Citation
Kim, M., "Three-Dimensional Numerical Study on the Pulsating Flow Inside Automotive Muffler with Complicated Flow Path," SAE Technical Paper 2001-01-0944, 2001, https://doi.org/10.4271/2001-01-0944.Also In
References
- Munjal M. L. “Acoustics of Ducts and Mufflers” John Wiley New York 1986
- Sullivan J. W. “A Method of Modeling Perforated Tube Muffler Components Application” J. Accost. Soc 1981
- Kim Y. H. “Experimental Study on Acoustic Wave Propagation in Circular Expansion Chamber with Flows” Winter Annual Meeting ASME 1989
- Yoshihiro, Yuzuru Shimamoto “A Numerical Method for Predicting Sound Characteristics and Pressure Losses of Silencers in Internal Combustion Engines” JSME J. of Fluids Engineering 92-0752 1992
- Eriksson L. J. Thawani P. T. Hoops R. H. “Acoustical Design and Evaluation of Silencers” Nelson Industries, Inc. Stoughton, Wisconsin 1981
- Eriksson L. J. “High order mode effects in circular ducts and expansion chambers” J. of Acoustical Society of America 68 545 550 1980
- Park S. y. et al. “The Study on the Flow Characteristics of Muffler with Volumetric Rate Change of Baffle Plate” KSAE 1995
- Ganesan V. Splading D. B. Murthy B. S. Experimental and Theoretical Investigation of Flow behind an Axisymmetric Baffle in a Circular Duct” AIAA 1980
- Cho J. H. Won Y. S. “A 3-D Flow Analysis in a Muffler Considering Pulsating Pressure of Exhaust Gas” KSAE 1998
- Yokhot V. Orszag, S. A. “Re-normalization Group Analysis of Turbulence: Basic Theory” J. of Scientific Computing 1 1986
- Yokhot V. Smith L. “The ε -expansion Derivation of Turbulence Models” J. of Scientific Computing 3 1992
- Speziale C. G. Thangam S. “Analysis of an RNG Based Turbulence Model for Separated Flows” NASA Contract Report, ICASE Report No.92-3 1992
- Monson D. J. Seegmiler H. L. Chen Y. S. “Comparison of Experiment with Calculation Using Curvature Corrected Zone and Two Equation Turbulence Models for a Two-Dimensional U-Duct” AIAA 90-1484 1990
- Thangam, S. Spezial, C. G. “Turbulent Flow Past a Backward-Facing Step: A Critical Evaluation of Two-Equation Models” AIAA Journal 30 5 1314 1320 1992
- Brankovis A. Syed S. “Validation of Reynolds Stress Turbulence Model in Generalized Coordinates” AIAA 91-1782 1991
- Leschziner M. A. “Numerical Implementation and Performance of Reynolds Stress Closures in Finite-Volume Computations of Re-circulating and Strongly Swirling Flows” Introduction to the Modeling of Turbulence 1991-02
- Shapiro, A. H. “Dynamics and Thermodynamics of Compressible Fluid Flow” Roland Press New York 1953
- Gerhart Philip M. “Fundamentals of Fluid mechanics (2nd ed.)” Addison Wesley New York 1996
- Lieman, H. W “Element of Gas Dynamics” John Wiley & Sons New York 1957
- Yoshihiro et al. “Analysis of Acoustic Characteristics and Pressure Losses in Intake Silencers by Numerical Simulation” JSME J. of Fluids Engineering 92-0992 1992