• Proceedings of the KSR Conference
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• 2008.11b
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• pp.1407-1412
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• 2008

Squeal of disk brake is a noise and self excited vibration with frequency range of $1{\sim}10Khz$ cause by the friction force between the disk and the pad of the automobile. Passengers in a cehicle feel uncomfortable. In this paper modal analysis of wheel brake system was performed in order to prediction of squeal phenomenon. It was shown that the prediction of system instability is possible by FEM. finite element model of that brake system was made. Some parts of a real brake was selected and modeled. The normal mode analysis method performs analyses of each brake system component. Experiment of modal analysis was performed for each brake components and experimental results were compared with analytical result from FEM.

• Journal of the Korean Society for Railway
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• v.16 no.4
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• pp.253-261
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• 2013

According to the measured results of KTX brake squeal noise in this study, high level brake noise occurred in a wide frequency range, 100~18,000Hz. To identify the sources of the brake squeal noise, unstable vibration modes due to brake disc/pad interaction were analyzed under various conditions by the finite element method. Complex eigenvalues for a brake unit with a disc and four pads were obtained. It was found that the real parts of the complex eigenvalues, that is, unstable vibration modes, were closely related to friction coefficients, pressure on the brake cylinders, elastic moduli of the components, and other conditions.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.963-963
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• 2008

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.3
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• pp.41-47
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• 2005

This paper deals with a squeal noise in a brake system. It has been proved that the squeal noise is influenced by the angular misalignment of a disk, disk run-out, with the previously experimental study. In this study, a cause of the noise is examined by using FE analysis program(SAMCEF) and numerical analyses with a derived analytical equation of the disk based on the experimental results. The FE analyses and numerical results show that the squeal noise is due to the disk run-out as the experimental results and the frequency component of the noise equals to that of a disk's bending mode arising from the Hopf bifurcation.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.595-600
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• 2004

This paper deals with a cause analysis of a squeal noise in a brake system. It has been proved that the squeal noise is influenced by the angular misalignment of a disk, disk run-out, with the previously experimental study. In this study, a cause of the noise is examined by using FE analysis program(SAMCEF) and numerical analyses with a derived analytical equation of the disk based on the experimental results. The FE analyses and numerical results show that the squeal noise is due to the disk run-out as the experimental results and the frequency component of the noise equals to that of a disk's bending mode arising from the Hopf bifurcation.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.05a
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• pp.505-508
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• 2002

AN EMBEDDED PC-BASED HARDWARE AND SOFTWARE SYSTEM HAS BEEN DEVELOPED TO AUTOMATE THE DATA ACQUISITION AND ANALYSIS OF BRAKE SQUEAL. THE DEVELOPED SYSTEM INTEGRATES ADVANCED SIGNAL CONDITIONING HARDWARE AND SOFTWARE TO ACQUIRE BRAKE NOISE AND VIBRATION DATA RAPIDLY, CONSISTENTLY AND OBJECTIVELY. A SPECIAL PEAK-PICKING ALGORITHM IS USED TO DETERMINE WHEN BRAKE NOISE OCCURS DURING A STOP EVENT AND ACTUALLY DEFINE FROM WHICH CORNER OF THE VEHICLE IT ORIGINATES. A SPECIAL NOISE-RATING TABLE IS FEATURED TO ENABLE THE USER TO DEVELOP CORRELATIONS BETWEEN DRIVER RATINGS AND OBJECTIVE MEASUREMENTS.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1996.10a
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• pp.98-103
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• 1996

Elimination of squeal noise generated during brake application is an important task for the improvement of comforts in vehicles. In this paper, the structure of the wet brake and its operation are described first, and the cause of the noise is analyzed by identifying how the factors such as torque, speed, oil pressure, lubricant, and friction material affect the noise. To verify the mechanism of generation of the noise, several experiments of brake applications are executed, Based upon the review on the technical papers and the results from the experiments, several solutions to reduce the noise, available in real applications, are suggested, and the feasibilities of them are confirmed through the applications to the current system.

• The Journal of the Acoustical Society of Korea
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• v.15 no.2E
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• pp.63-75
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• 1996

The squeal vibration of a drum is the major source of brake noise. In this system the binary flutter model of squeal vibration was employed for the drum brake of a passenger car. The vibration analysis of a drum brake was performed by using normal modes, which are obtained by variational method. An improved method for the estimation of shoe modes is proposed and the results are compared with the exact solutions. Numerical results for the coupled system of drum and shoes good agreement with the results of experimental model analysis and those obtained by FE analysis.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.10 no.6
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• pp.21-28
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• 2001

Analysis of squeal noise generated during brake operation is an important task for the improvement of brake noise prob-lem. By the use of measuring instrument and techniques, test and evaluation process are to be developed systematically in quantitative analysis. The cost far test and evaluation 7an be reduced, and the technical power can be raised by the devel- oped system.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.22 no.12
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• pp.1206-1212
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• 2012

The brake squeal propensity due to the friction-velocity curve is numerically investigated. The finite element models for the disc and pad are correlated with the modal test. In the friction-engaged system modeling, the friction function is linearized at the equilibrium. The damping term induced by friction-velocity slope is incorporated into the equations of motion. In the complex eigenvalue analysis, it is found that the pad shear mode is very sensitive to the friction curve. The results shows that the squeal propensity of the pad shear mode can be controlled by the design parameters such as pressure and stiffness.