• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.85-86
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• 2006

It presented the approach method for the station braking noise present condition and a braking noise reduction plan escape of the KTX train. The research which it sees the technical ground it will be able to accomplish the station braking noise reduction of the KTX vehicle with base the questing matter where the escape one thing is big there is a possibility of doing.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 추계학술대회 논문집
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• pp.751-752
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• 2010

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 추계학술대회 논문집
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• pp.578-579
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• 2009

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 춘계학술대회 논문집
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• pp.373-374
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• 2011

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 추계학술대회 논문집
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• pp.771-772
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• 2011

• Tribology and Lubricants
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• 제36권5호
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• pp.274-278
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• 2020

This study investigates the possibility of reducing squeal noise generated at the contact point between an elastomer and glass by using the properties of a magneto-rheological elastomer (MRE) whose stiffness changes with the application of a magnetic field. Previously, squeal noise was mainly observed in the unstable section caused by the weakening of friction due to velocity. Previous studies have shown that squeal noise decreases as the stiffness increases. Accordingly, this study is conducted to control the unstable area of the friction curve and to reduce the noise by inducing the stiffness change of the MRE by applying a magnetic field. The friction, vibration, and noise characteristics are measured using a reciprocating friction tester. The frequency ranges of vibration and noise measured with the accelerometer and sound sensor show similar results. When a magnetic field is applied to the MRE, there is significantly lower noise compared with the case without the application of the magnetic field. The average coefficient of friction decreases with the application of the magnetic field. The maximum coefficient of friction increases rapidly at the turning point and decreases when the magnetic field is applied. This shows that the mechanical properties of the MRE change due to the magnetic field, and the noise and friction coefficient also decrease.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2010년도 추계학술대회 논문집
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• pp.362-367
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• 2010

This paper deals with the correlation between the interior noise and the floor vibration of the train from rolling, impulse and friction in Busan Metro line 3. The correlation is verified by sound and vibration measurement causing friction between the railway and the wheel. If ANC(Active Noise Control) system can reduce 5 dB in below 500 Hz, the sound pressure level of the whole band pass can be reduced about 1.8-4.8 dB in squeal noise. Curve squeal noise is the intense high frequency tonal that can occur when a railway vehicle transverses a curve. The frequency range is from around 500 to almost 20,000 Hz, with noise levels up to about 15 dB in curve.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1690-1695
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• 2003

In order to investigate the mechanism of brake squeal noise, the sound and vibration of an actua1 brake system were measured using a brake dynamometer. The experimental results show that disc run-out varies with brake line pressure and the factor of squeal generation is the run-out due to the misalignment of brake disk. A three degrees of freedom friction model is developed for the disk brake system where the run-out effect and nonlinear friction characteristic are considered. The results of numerical analysis of the model agree well with the experimental results. Also, the stability analysis of the model was performed to predict the generation of brake squeal due to the design parameter modification of brake systems. The results show that the squeal generation depends on the nm-out rather than the friction characteristic between the pad and the disk of brake.

• 대한기계학회논문집A
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• 제32권11호
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• pp.930-936
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• 2008

This paper studies the effect of pad at initial stage and wear during braking on the dynamic contact pressure distribution. Wear is influenced by variable factor (contact pressure, sliding speed, radius, temperature) during dynamic braking and variation in contact pressure distribution. Many researchers have conducted complex eigenvalue analysis considering wear characteristic with Lim and Ashby wear map. The conventional analysis method is assumed the pad has smooth and flat surfaces. The purpose of this paper is to validate that wear rate induced by braking is considered for the precise squeal prediction. After obtaining pad wear from experiment, it is incorporated with FE model of brake system. Finally, the comparisons in fugitive nature of squeal will be carried out between the complex eigenvalue analysis and noise dynamometer experiment.

• 한국정밀공학회지
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• 제15권9호
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• pp.111-116
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• 1998

The squeal of drum brakes was investigated numerically and experimentally. Modal testings were performed for shoes, drums, backing plates and their assemblies. In order to predict the squeal phenomena, stability analysis was performed based on a simplified self-excited vibration model. Based on modal testings, the dynamic properties of the brake elements and the parameters used in this analysis were determined. The geometries of shoes and drums were also considered. The result shows that the modification methods of the shoe and the drum design are feasible for noise reduction.