• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 추계학술대회논문집
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• pp.606-607
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• 2008

Nowadays, noise and vibration phenomena of a disc brake system have been given various names that provide some definitions of sound and vibration emitted such as grind, grunt, moan, squeak, squeal, judder and wire brush. The most common and annoying noise of a disc brake system is squeal noise. It is defined as noise whose frequency content is 1 kHz and higher with excessively high and irrigating sound pressure levels. In this paper, the noise and vibration characteristics of a disc brake system have been investigated to develop the fusion-type friction material, which overcomes the low steel and non-asbestos organic friction materials. For the purpose, both experimental evaluation and complex eigenvalue analysis have been carried out.

• 대한기계학회논문집A
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• 제38권6호
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• pp.683-689
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• 2014

본 연구에서는 구조해석 시뮬레이션을 통해 저주파 스퀼을 유발하는 여러 요소를 분석하였다. 해석을 위한 프로그램은 ABAQUS 를 사용하였으며 동적 불안정성을 판명하기 위한 방법으로는 복소 고유치 해석을 채택하였다. 스퀼 유발 요소와 관련된 핵심적인 5 가지 인자를 선정하였고 각각 3 수준으로 분류하였다. 이를 분석하기 위해 실험계획법을 적용하였고, 파라미터 영향도 분석에는 평균분석을 적용하였다. 이을 통해 영향도가 큰 인자를 선별하였고 타당한 해석 기법 및 파라미터 영향분석을 수행하였다.

• 한국철도학회논문집
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• 제16권4호
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• pp.253-261
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• 2013

KTX 열차가 정거장에서 정차 시 측정한 제동 스퀼소음은 저주파에서부터 18,000Hz의 고주파 영역에 걸쳐 관찰되었다. 제동 스퀼소음이 제동디스크/패드의 상호작용에 의한 불안정 진동모드에 의해 발생한다는 가정 하에 유한요소법을 적용하여 하나의 제동디스크와 4개의 제동패드로 구성된 제동 유니트에 대해 유한요소 모델링을 하고 마찰계수, 마찰면에 작용하는 압력, 마찰재와 백플레이트의 탄성계수 등 여러 파라미터의 특성값을 변경해 가면서 제동 유니트의 불안정 진동모드에 미치는 영향을 해석하고 각 파라미터의 영향을 분석하였다. 해석결과에 의하면 불안정 진동모드는 이러한 변수들과 밀접한 관련이 있음을 알 수 있었다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 춘계학술대회논문집
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• pp.861-864
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• 2005

Brake noise has been one of the most difficult concerns in the automotive industry. Although substantial research has been conducted to predict and eliminate brake noise, there is yet no method to completely suppress brake noise. Furthermore, little effort has been made to improve noise and vibration characteristics of the railway brake system. The amount of sound energy radiated from the railway brake system is much larger than that from the automobile, and it causes discomfort of passengers in the station. In this paper, noise and vibration caused by the braking force of the KTX vehicle have been measured and analysed. Results show that noise level increases abruptly right before a train comes to a complete stop. Furthermore, typical characteristics of the disk brake squeal have been observed.

• 소음진동
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• 제10권4호
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• pp.629-635
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• 2000

Wheel /rail interaction has been known as a major source of railway noise. In this paper, a low noise wheel structure is developed and its effect on noise reduction is investigated. The developed low noise wheel employees a rubber material inserted into a steel rim or mounted on the wheel surface. Since the low noise wheel has low stiffness and high damping ratio compared to a solid wheel, the measurement results show that it reduces the rolling and squeal noise. It turns out that the proposed wheel could reduce interior noise level by 4∼5dB(A) and vehicle vibration level by 7∼10 dB. Although the proposed structure seems to be promising in noise reduction of railway vehicles, the low noise wheel is to be verified in endurance and cost effect.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.115-122
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• 2007

The noises which occurs from the rolling stock can be divided largely into three classes and they are Rolling noise, Traction noise and Aerodynamic noise. In the event of braking the rolling stock which enter into the station, Brake shoes cause Fraction noise (braking noise) and excessive braking noise makes passengers and operators uncomfortable. This study is to reduce squeal noise and minimize displeasure by measuring the braking noise and defining the major noise sources and noise mechanism

• 한국소음진동공학회논문집
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• 제11권4호
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• pp.58-64
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• 2001

Sound absorbing materials are applied to the exposed surfaces of curvet subway tunnel for the reduction of curving noise level. Before the treatment, acoustical engineering simulation is performed to predict the noise level reduction for different kinds and amounts of absorbing material. The principle of geometrical acoustics is utilized to perform the simulation efficiently and accurately. The noise bevels of the inside and outside of running car body are measured to find the noise level reduction. The average noise level reduction of 8 dB has been attained. It has been shown that the simulated results are comparable to the measured ones.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 춘계학술대회논문집
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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.

• 한국공작기계학회논문집
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• 제10권6호
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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.

• 한국소음진동공학회논문집
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• 제24권1호
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• pp.28-34
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• 2014

This study provides the numerical finite-element method(FEM) estimating the friction noise induced by the negative slope in the friction-velocity curve. The friction noise due to the friction-velocity curve is experimentally investigated through the pin-on-disk setup. The measured squeal frequency is estimated by FEM. The friction curve is measured by the friction test, then it is applied to the complex eigenvalue analysis. The results shows that the experimental squeal frequency can be determined by the FEM analysis. Also, it is emphasized that the negative friction-velocity slope is essential in generating friction noise in the pin-on-disc system.