• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.3410-3415
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• 2014

The heat generated by electronic devices can result in performance degradation. Therefore, a heat sink has been used to release the operating heat into the air outside. This study addressed a methodology for a heat sink with an inner tunnel. Under forced convection conditions, the heat transfer characteristics were different so the cooling and heating performances were studied for the heat sink with an inner tunnel. This was evaluated by performing the experimental test examining the heat transfer characteristics related to the variance in time and temperature distribution. In the cooling experiment, the temperature of the A-shape was lower than that of the B-shape, when the voltage was 10 V. These experimental results indicate the optimal cooling effect. In a heating experiment, the temperature of the A-shape was higher than that of the B-shape, when the voltage was 13 V. The experimental results showed that the temperature and efficiency of the A-shape were higher than those of the B-shape.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.2
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• pp.183-190
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• 2011

As the number of mobile subscribers has increased recently, the demand for more number of base stations has increased. However, because of the shortage of sites for constructing base stations, a mobile communication module needs to be small in size. To minimize the size of the module, the size of the heat sink attached to the outside of the module should be minimized. Furthermore, the temperature of each electronic component of the module should be lower than the allowable temperature so that thermal stability can be maintained. A commercial PIDO (process integration and design optimization) tool PIAnO and a commercial CFD (computational fluid dynamics) tool FLOTHERM are used to minimize the size of the module while the constraints on the temperatures of the twelve electronic components are satisfied. As a result of design optimization, the volume of the heat sink is reduced by 41.9% while all the constraints on the temperature of the twelve electronic components of the module are satisfied.

• Journal of Energy Engineering
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• v.9 no.3
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• pp.212-220
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• 2000

히트파이프 히트싱크의 라디에이터를 통과하는 공기 유동에 대한 열전달 및 유동 압력 강하를 구하기 위한 연구를 수행하였다. 이 라디에이터는 평판 휜-관 구조이며, 평판휜에 4개의 히트파이프가 유동 방향으로 정격 배열 되어있다. 입구 공기 속도 2.5~4m/s에 대해 열전달 성능실험과 수치해석을 수행하였다. 각 히트파이프의 단위 길이당 열속이 583.3W/m, 입구 공기 속도가 3m/s일때 총합 대류 열전달계수값은 약 32W/$m^2$K, 압력 강하는 8mmAq이었다. 전체속도범위에서 실험결과와 수치 해석 결과 사이에는 약 5%의 미만의 일치를 보였다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.8
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• pp.664-670
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• 2002

A heat sink (HS) system using heat pipes for electronics systems was studied. The experimental results indicate that a cooling capacity of up to 150w at an overall temperature difference of $50^{\circ}C$ can be attainable. The heat sink design program also showed that a computer simulation can predict the most of the parameters involved. To do so, however, the interior temperature distribution had to be verified by experimental results. The current simulation results were close to the experimental results in acceptable range. The simulation study showed that the design program can be a good tool to predict the effects of various parameters involved in the optimum design of the heat sink.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.5
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• pp.467-472
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• 2011

The heat transfer over a radial heat sink, adapted for LED (light emitting diode) downlights, was experimentally and analytically investigated. We added radiation heat transfer into a previous calculation that neglected this factor. The numerical results agreed well with experimental results. Parametric studies were performed to compare the effects of the geometric parameters (fin length, fin height, ideal number of fins) and the operating parameter (heat flux) on the average heat-sink temperature from the heat-sink array. We found the fin length that maximizes the heattransfer performance. As the emissivity increased, the effect of geometric parameters on the radiation heat transfer decreased.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2438-2443
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• 2007

In order to guarantee the performance of electronic products. It is needed to improve the cooling performance of heat sink. So this paper has been made to investigate the cooling performance for the aluminum heat sink using pulsating heat pipe(PHP). The pulsating heat pipe was used as a heat spreader. Working fluid was R-22. Heater (50 mm ${\times}$ 50 mm ${\times}$ 3mm) was attached to heat sink and it generated 30W, 60W, 80W, 100W. Heat sink was tested for forced convection with 1${\sim}$4m/s of inlet air velocity. And both type heat sinks were carried out by using CFD simulation. This study showed that pulsating heat pipe can be a good tool to improve cooling performance of heat sink.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.10a
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• pp.99-102
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• 2009

Fixture 일체형 LED 다운라이트(Downlight)의 광 효율 향상을 위하여 LED 장착위치 및 Reflector 길이, 히트싱크(Heat sink) 형태에 따른 광도(luminous intensity)와 기구효율(luminaire efficiency)을 시뮬레이션을 통하여 비교분석 하였다. 또한 히트싱크의 방열 설계를 시뮬레이션 하고 상용 LED 패키지 (Cree, XP-E P4)를 사용하여 시제품을 제작 하여 그 성능을 평가하였다. 그 결과 광속 9661m, 상관 색온도(CCT) 3,060K, 연색지수(CRI) 82의 광 특성을 갖는 LED 다운라이트를 개발하였다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.1 s.232
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• pp.16-26
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• 2005

Air-cooled heat sinks are employed in many electronic cooling applications since they provide significant heat transfer enhancement and operational flexibility. Strip-shaped fin heat sink is of interest and needs to be investigated as general cooling products for more applicability. The purposes of this study are to evaluate heat sink performance without bypass flow condition and to determine optimal heat sink geometries. The results show that the decreasing rate of thermal resistance of a heat sink decreases with increasing inlet air velocity, and the increasing rate of pressure drop increases with increasing inlet air velocity, but is not affected by input power. The increasing rate of optimal longitudinal fin spacing is larger than that of transverse fin spacing. The strip fin heat sink tested in this study showed better cooling performance compared to that of other plate fin type.matism. 2004; 50(11): 3504-3515.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.8
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• pp.728-740
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• 2004

Heat sink has extended surface area for enhanced heat transfer. The enhanced convection heat transfer has been used widely, such as cooling electronic chips in the electronics industry. Heat sink usually requires an increase in the heat transfer and a decrease in the pressure drop, and must improve the performance in the flow field of industrial plants. In this study, wing fin heat sink was studied and tests were conducted in a rectangular cross sectional channel with wing fin heat sinks. The leading and trailing ends of a wing fin have a sharp edge, simulating the airfoil feature. Empirical correlations have been developed for wing fin heat sink types. And wing fin heat sinks have better cooling performance than elliptic fin and square fin types.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.133-134
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• 2005

When Power MOSFET is operated, it causes lots of heat, which influences negatively on the characteristics of the devices and shorten the lifespan of them. Therefore, a heat sink should be mounted on to emit the heat. In this experiment, we've found the changes of the characteristics of Thermal Transient of MOSFET when a heat sink is applied. In addition, we've found other changes when heat sink compound is applied as well.