• Journal of the Korea Convergence Society
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• v.10 no.12
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• pp.287-292
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• 2019

This paper analyzes the thermal behaviors of genuine discs used in automobiles and discs coming out of tuning products through FEM analysis. Modeling with genuine disk modeling and tuning disks Model-1, Model-2, Model-3 and analyzing the disk rotation speed was set to 1000rpm. When the brake is operated, the thermal behavior of the disk surface, such as the operating temperature caused by the disk and pad contact, the friction surface temperature after the disk stop, and the thermal deformation, were analyzed. When the brake was activated (0-4.5 seconds), the tuning disk showed 34℃ higher than the original disk, and after the disk stopped (40.5 seconds), the tuning disk was analyzed 18℃ lowe, deformation due to the disk heat was deformed by 0.3mm for the tuning disk. Although there is an effect to reduce the fading phenomenon due to the thermal behavior of the pure disk and the tuning disk, it can be observed that there is no significant change in the thermal behavior due to the hole processing and the disk surface processing of the tuning disk.

• Journal of the Korea Convergence Society
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• v.11 no.11
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• pp.233-237
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• 2020

In this study, the thermal analysis on the brake disc of electric kickboard was analyzed. The different heat is transmitted depending on the pad contact surface of brake disc. The trend that the temperature decreases at the part away from the contact surface was almost constant. And model A showed a slightly lower temperature distribution than model B. Model A has a maximum equivalent stress of 7% higher than model B. By being applied with the higher heat transfer above the contact surface, it is thought that model B has a greater strength than model A if the design takes into account the corner of the brake disc. If this study result is utilized to the design of electric kickboard, the design of brake disc with better strength is considered to be established. The durability of brake against the heat can be evaluated by applying this study result to the brake disc of electric kickboard. And it is seen that the result can be the design of brake with strength and the aesthetic convergence.

• Journal of the Korean Institute of Gas
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• v.20 no.1
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• pp.40-45
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• 2016

Brake judder is one of the most serous problems in automotive-brake systems.it has not been eradicated despite all the efforts that many researchers and engineers have made the reduce it by studying its causes and mechanisms. Brake discs play a significant role in judder.The driver experiences judder as vibrations in the steering wheel,brake pedal and floor.in the higher freqency range.the structural vibrations are accompanied by a sound. Brake judder primarily affects the comfort but could,when confronting an inexperienced driver for the first time,lead to faulty reactions and reduced driving safety.

• Composites Research
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• v.13 no.6
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• pp.55-62
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• 2000

The strength test was done for the Carbon/Carbon rotor disk which is the critical part of a carbon/carbon brake system in an operating time. The loading fixture was designed for the static strength test of a single carbon/carbon brake disk using finite element analysis. To simulate the real dynamic system in a static condition, the friction surface of the rotor disk was fixed and static load was applied to the rotor slot in the circumferential direction. The described failure mechanism of the brake disk can be described as matrix cracking occurred first at the contact surface of the rotor slot, subsequent delamination from the cracked contact surface, and the final fracture at the notch of the rotor.

• Journal of Digital Convergence
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• v.13 no.11
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• pp.171-178
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• 2015

The disk cover is installed to protect brake disk and calliper and it's removed right before delivering to customers. The temperature of disk cover was measured driving test vehicles(2000cc, diesel) in this study. The highest temperature measured for the driving test(120km/h-braking(0.3G)-stop-120km/h-braking(0.5G)-stop) was $260{\sim}270^{\circ}C$ in the upper part of the disk cover and the temperature varied considerably around the disk cover. It can be inferred from this temperature distribution around the cover that the major heat transfer from hot disk to cover was through convection. In other words, the hot air generated by braking friction moved up to the upper part of the disk cover. And only the upper area of the disk cover was melted down during this driving test. The thickness of disk cover was increased to 1.0mm from 0.7mm and 1 paper of masking tape was pasted in the upper region of the disk cover. Then the cover endured the heated air formed by braking friction during the driving test.

• Proceeding of EDISON Challenge
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• 2017.03a
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• pp.351-357
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• 2017

차량용 브레이크의 성능은 브레이크 디스크 로터의 냉각 성능과 밀접한 관련이 있다. 냉각 성능 향상을 위해 디스크 로터에 구멍을 뚫거나 홈을 깎아내어 열 전달면을 극대화 시키거나 열 전도도가 높은 재료에 대한 연구가 활발하게 진행되고 있다. 본 연구에서는 각각 형상이 다른 디스크 브레이크 시스템의 방열 및 제동 성능, 패드 압력에 대한 응력을 분석하고 온도장 근사 및 열전도 해석 프로그램(Heat_transfer, KAIST, EDISON)과 Elastic-Plastic Analysis SW(CSD_EPLAST, 서울과학기술대학교, EDISON) 및 ABAQUS를 이용해 각각의 냉각 성능 및 응력 분포를 비교 분석한다.

• Journal of the Korea Convergence Society
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• v.9 no.1
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• pp.283-289
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• 2018

In automotive disc brake systems, frictional heat is not uniformly dispersed for reasons such as heat flux and thermal deformation. The thermoelastic deformation due to the frictional heat affects the contact pressure distribution and the contact load may be concentrated on the contact portion on the the disc brake surface, resulting in thermoelastic instability. In this study, thermal analysis and thermal deformation analysis considering the contact between disk and pad occurred during braking through 3D axial symmetry model with reference to the experimental equation and Kao's analysis method of contact pressure of disk and pad. ANSYS is used to analyze the thermal and elastic instability problems occurring at the contact surface between the disk and the pad, considering both the thermal and mechanical loads. A 3D axisymmetric model with direct contact between the disk and the pad was constructed to more accurately observe the thermal behavior of the disk by observing the frictional surface temperature, thermal deformation and contact thermal stress of the disk.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.941-947
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• 2008

In the braking of a railroad car, mechanical brake systems using wheel tread and brake disk are applied as well as electrical brake systems by regenerator and rheostat. During disk braking, kinetic energy of the vehicle is converted into thermal energy through friction between disk and brake pad. And it causes high temperature concentration and generates thermal crack on the brake disk surface. In this study, comparative test process for heat-resistance of candidate materials was designed for development of brake disk materials having high heat-resistance. We also verified the efficiency of the process by experiments using conventional brake disk materials.

• Journal of the Korea Convergence Society
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• v.11 no.6
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• pp.209-213
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• 2020

In this study, the model A with the existing shape used at racing car and the model B with light weight were designed. The structural analysis with thermal deformation and stress were carried out. Model A shows that the maximum temperature is lower than model B. The cooling performance due to the shape of the disk without any other cooling conditions can be shown to be better for model A. Model A was seen to be superior in durability as the thermal stress reduced by almost twice as much as model B. The part where the greatest stress occurred appeared to be the hole jointed with the hub regardless of its shape. The analysis results at this study are seen to be useful at designing the shape of the actual vehicle brake disc. The analysis results obtained in this study can be applied at grasping the strength of the brake disk for racing car practically. By utilizing the analysis result of the brake disk for racing car, this study is seen as the convergence study that the aesthetic design and analysis are applied.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.6
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• pp.45-51
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• 2005

Braking performance of a vehicle can be significantly affected by the temperature increment in the brake system. Therefore, the important problem in brake system is to reduce the thermal effect by friction heat. Recently, many studies have been performed and good results have been reported on the prediction of the brake disk temperature. However, the study on the pad, piston and brake fluid temperature is rarely found despite of its importance. In this study, the temperature distribution of the disc brake system is studied according to the material properties of brake piston. Vehicle deceleration, weight distribution by deceleration, disc-pad heat division and the cooling of brake components are considered in the analysis of heat transfer. Unsteady state temperature distributions are analyzed by using the finite element method and the numerical results are compared with the experimental data.