• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.1163-1164
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• 2011

• Proceedings of the KAIS Fall Conference
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• 2008.05a
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• pp.170-172
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• 2008

본 논문은 LED조명기구의 상용화에 문제가 되고 있는 방열설계에 관한 논문으로서, CF-design을 이용한 방열해석을 통하여 문제해결의 방법을 제시한다. 해석 결과 시뮬레이션 값과 시작품 제작 후 측정 온도와의 차이가 6[$^{\circ}C$]이하로 도출되었으며 주어진 제 요소들을 잘 활용하면 실제작품의 목표치에 근접하는 결과를 얻을 수 있다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.10
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• pp.4398-4404
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• 2012

This thesis was conducted a numerical analysis on the radiant heat performance according to factors of design of heat sink for cooling of the automotive LED head lamp. The heat sinks were designed with 5 different types to fit the limited internal space by formula based on an existing product (Type 1). Designed heat sinks of five types were analyzed by ANSYS CFD V12.1, and the analysis results were compared with the existing type. The results of simulation were analyzed temperature distribution and average temperature, air flow characteristic, heat flux etc. This thesis was researched on the correlation of the cooling performance according to the heat sink structure and the fin shape. Through numerical analysis, could be confirmed heat sink Type 2 as the best results.

• Proceedings of the KAIS Fall Conference
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• 2010.05b
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• pp.985-987
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• 2010

신성장 동력 산업으로 분류된 LED 조명제품은 긴 수명과 고효율 에너지 제품으로 인해 많은 주목을 받고 있지만, LED 조명제품이 고출력화 될수록 정션온도가 증가하면서 수명 단축 및 출력 저하의 문제가 발생한다. 따라서, 본 연구에서는 조명등 정션온도의 최소화를 위한 방안을 도출하고 수치해석을 통해 방열 성능을 예측하였다. 또한, 10W 이상의 고출력인 경우 방열면적의 증가로 인한 조명등의 중량 증대가 문제시 되므로 경량화를 위한 방열해석도 수행하였다.

• 전자공학회논문지 IE
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• v.48 no.2
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• pp.12-18
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• 2011

In this paper, did numerical simulation to confirm LED module for lighting and protection against heat special quality of heat sink device. Analysis was gone dividing on case that emitting light side turns normalcy department considering that eat of device according to usage and case that turn down looking being street lamp of 200 W or security appointment lighting device analysis case, and also, volume of thermal element divides on big case and small case and analyzed. Confirmed that can do so that may discharge LED's thermal value to outside enough in analysis wave and current heat sink shape, and investigated that difference of protection against heat performance according to position of device and size of thermal element appears.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.3
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• pp.1027-1032
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• 2013

LED is standing in the limelight as a light part of the low-carbon green energy. While LEDs are eco-friendly, efficient and durable, extreme heat rises can cause their durability to decrease, with 80% of the power supply being turned into heat energy. Heat radiation systems are important because rising temperatures affect the lifetime of LED elements. Therefore, in this paper, thermal analysis was performed for the shape of heat sink to the LED bulb. Also, it is applied the temperature control systems to our products for optimal performance.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.7
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• pp.1484-1488
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• 2009

This thesis is about Heat-sink design which is considered as the biggest problems for commercialization of LED lighting and suggests how to solve the problems though analysis on heat-sink using COMSOL. The temperature difference after simulation value and modelling was $10^{\circ}C$by Transient analysis of Heat Transfer Module which is in the COMSOL Multiphysics. The result approximated the object which is close to actual lighting, when various elements are used according to temperature change of interior and exterior surroundings LED lighting is set up.

• Journal of Energy Engineering
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• v.26 no.2
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• pp.64-72
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• 2017

The performance analysis of the 70 W class LED lighting system suitable for the Middle East environment was performed using the lumped parameter model. The LED light is composed of a heating substrate, a heat pipe, and a heat sink. We divided the LED lights into four objects and applied energy equilibrium to each of them to establish four lumped nonlinear differential equations. The solution of the simultaneous equations was obtained by the Runge-Kutta method. Convective heat transfer coefficients of the lumped model were obtained by multidimensional CFD analysis. As a result of comparison with experiment, it was found that the heating substrate had an error of $1.5^{\circ}C$ and the upper heat sink had an error of $1.8^{\circ}C$ and the relative error was about 0.6 %. Using this model, temperature distribution analysis was performed for normal operating conditions with an ambient temperature of $55^{\circ}C$, with sunlight only, with abnormal operating conditions with sunlight, and without an upper heat sink.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.2
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• pp.401-407
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• 2014

There are increasing interests in COB (Chip On Board) that densely arranged many LED chips on one board in order to solve the heat issue. There are many problems being on the rise: the lifespan decreases as the temperature of LED devices increases; Red Shift phenomenon, in which wave length of spectral line moves from original wave length to long wave length, occurs; and optical power decreases as $T_j$ increases. In order to resolve such problems, this study selected the optimum thickness and length of Fin, planned the second Heat sink that is optimum for COB LED with 15W, and analyzed thermal mode by Solid Works Flow Simulation through 15W COB packaging with the planned Heat sink. 15W COB down-light Heat sink that is produced based on this analysis was utilized to analyze thermal mode through contact thermometer and electrical properties through Kelthley 2430.

• Korean Journal of Optics and Photonics
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• v.20 no.4
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• pp.236-240
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• 2009

LED modules, based on MCPCB with a hard barrier oxide layer and an improved thermal dissipation property, are presented. Reflecting cups were also formed on the surface of the MCPCB such that optical coupling between neighboring chips was minimized for improving the photon absorption loss. LED chips were directly attached on the MCPCB by using the COB (Chip On Board) scheme. The LED modules showed significantly enhanced light outputs, compared to the LED modules based on conventional MCPCBs.