• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2011년 춘계학술대회논문집
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• pp.225-229
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• 2011

The aluminum composite panel are widely used for the external materials of high rise building because of well insulation of heat and sound and improved Constructability. However, the polyethylene in main material of the aluminum composite panel shows weakness in thermal and fire resistances. For this reason, flame is spread more quickly when the fire break out. Therefore, the potentiality of fire spread to the exterior wall is high due to difficulty of early extinguishment and effect of external air. In this study, numerical investigation was performed by using FDS program for flame spread characteristics with various external air velocity and direction in ten-story building with the aluminum composite external materials. As a result, the flame spread velocity is 0.134m/s and it takes 224 seconds for flames to spread to the 10th floor without external air velocity. however, the flame spread velocity decreases 40% and it takes 348 seconds for flames to spread to the 10th floor when external air velocity is 2.5 m/s. and air direction is little effect compared to air velocity.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 한국추진공학회 1998년도 제11회 학술강연회논문집
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• pp.19-19
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• 1998

라이너를 포함한 필라멘트 와인딩 복합재 압력용기의 성능향상을 위한 효율적인 구조최적 설계방안을 제시하였다. 이를 위해 온도효과가 고려된 비선형 유한요소법을 이용하여 각 층에서의 응력해석과 파손해석을 수행하였다. 또한 설계변수로 라이너의 두께와 헬리컬 적층두께, 실린더를 따라 변하는 직각 적층두께를 설정하였다. 모든 설계변수들에 대한 강도비 민감도를 유도하였으며 헬리컬 적층두께에 대한 강도비 민감도를 유지하기 위해 측지 등장력 돔설계 방법을 고려하였다. 구조 최적설계결과, 실린더를 따라 직각 적층두께를 최적으로 분포시켜 강성을 효과적으로 배열하였으므로 적층두께를 일정하게 고려한 경우보다 더 경량화 시킬 수 있었다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 한국정밀공학회 2000년도 추계학술대회 논문집
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• pp.433-436
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• 2000

For a new design of a automotive brake system, it appears to be very important to examine the temperature and thermal stresses distribution in the brake drum. In the direct measurement of them, however, a number of difficulties are involved. In this study, simulation on temperature and thermal stress distributions in an A1-MMC brake drum of a commercial vehicle during 15 braking operations was carried out using the finite element analysis(FEA1. The effect of a circumferential fin near open end of the brake drum on the temperature rise and stresses was also examined.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.393-394
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• 2006

This study introduces the testing results of the composite carbody which is applied to tilting train. The composite carbody is made of aluminum honeycomb structure materials like a sandwich. The static load test was performed to evaluate the structural characteristic and stability of the composite carbody. Considering the vertical, compressive, twisting load and 3-point supporting type as a testing terms, the structural stability of a carbody was evaluated.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.217-218
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• 2007

Aluminum 분말과 고분자를 혼합하여 고분자-금속 복합재료(polymer-metal composite)를 만들어 copper foil과 기판의 접착력을 평가하였다. Tape casting 방법을 이용하여 sheet 만들고 vacuum lamination으로 PCB(Printed Circuit Board)기판을 제조한 후 포토공정으로 peel strength pattern을 형성하였으며, 본 연구에서는 최적의 aluminum 조건을 찾기 위하여 압력, 온도, copper foil의 표면 상태와 silane 표면 코팅에 따른 aluminum-polymer복합재료의 peel strength의 변화를 확인하였다. 최적의 조건은 silane 표면 코팅 처리를 한 aluminum 분말로 $210^{\circ}C$에서 $9.7kg/cm^2$ 압력으로 matte면의 돌기 크기가 크며, 응집이 잘 되어있는 copper foil을 사용하여 13.89N의 우수한 peel strength를 구현 할 수 있었다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 한국추진공학회 2009년도 제33회 추계학술대회논문집
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• pp.453-456
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• 2009

Impact resistance of shape memory alloy hybrid composite(SMAHC) plates were experimentally investigated. Shape memory alloy(SMA) have large failure strain and failure stress and can absorb large strain energies through phase transformation. SMA wires were embedded in composite plates to improve their weak impact resistance. Tensile tests of SMA wires were performed at various temperature to investigate their thermo-mechanical properties. Low-Velocity impact tests of several types of composite plates with SMA/Al/Fe were performed. Embedding SMA wires was most effective to improve impact resistance of composite plates. The effects of SMA position on impact resistance were also investigated.

• Composites Research
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• 제26권2호
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• pp.116-122
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• 2013

In this study, impact behavior of aluminium and glass-fiber structure is studied under low impact velocity. Compression test is carried out to investigate the compressive strength of the specimens. The degree of damage is observed using microscopy and compared with the experimental analysis data. The maximum load capacity, impact strength and elastic energy of glass-fiber honeycomb sandwich panel are more than the aluminium honeycomb sandwich panel.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• 제31권5호
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• pp.110-116
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• 2003

With the growth of aircraft performance and needs for light aircraft, the problems associated with hail impacts on aircraft during flights and grounding become and important issue. These hail encounters can cause severe damages to aircraft and result in major concerns in safety and cost. Since nearly all external components of the commercial and military aircraft-in particular, the nose section and the leading edge of the wing and tail-are subject to damages, much effort has been put into understanding of this problem. However, most of the previous studies have focused on the composite components and few results have been reported for the metallic components. In this paper, we study the ice impacts on the aluminum component with the finite element analysis method utilizing commercial non-linear dynamics solver LS-DYNA. The results are compared with the experimental data and a simple measure of the ice impact effects is proposed.

• Composites Research
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• 제36권6호
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• pp.435-440
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• 2023

This study aimed to enhance the thermal conductivity of B₄C/Al composite materials, commonly used in transport/storage containers for spent nuclear fuel, by incorporating both boron carbide (B₄C) and cubic boron nitride(cBN) as reinforcing agents in an aluminum (Al) matrix. The composite materials were successfully manufactured through a stir casting process and practical neutron-absorbing materials were obtained by rolling the fabricated composite ingot. The evaluation of the thermal conductivity of the fabricated composites was carried out because thermal conductivity is critical for neutron absorbing materials. The thermal conductivity measurement results indicated an approximately 3% increase in thermal conductivity under the same volume fraction when compared to composite materials using only B₄C particles. Through neutron absorption cross-sectional area calculations, it was confirmed that the neutron absorption capability decreased to a negligible level. Based on the findings of this study, new design approaches for neutron absorption materials are proposed, contributing to the development of high-performance transport/storage containers.

• Composites Research
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• 제23권6호
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• pp.7-13
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• 2010

Type3 cylinder is a composite pressure vessel fully over-wrapped with carbon/epoxy composite layers over an aluminum liner, which is the most ideal and safe high pressure gas container for CNG vehicles due to the lightweight and the leakage-before-burst characteristics. During service in CNG vehicle, if a fiber cut damage occurs in outer composite layers, it can degrade structural performance, reducing cycling life from the original design life. In this study, finite element modeling and analysis technique for the composite cylinder with fiber-cut crack damage is presented. Because FE analysis of type3 cylinder is path dependant due to plastic deformation of aluminum liner in autofrettage process, method to introduce a crack into FE model affect analysis result. A crack should be introduced after autofrettage in analysis step considering real circumstances where crack occurs during usage in service. For realistic simulation of this situation, FE modeling and analysis technique introducing a crack in the middle of analysis step is presented and the results are compared with usual FE analysis which has initial crack in the model from the beginning of analysis. Proposed analysis technique can be used effectively in the evaluation of influence of damage on composite layers of type3 cylinder and establish inspection criteria of composite cylinder in service.