방열핀 형상이 UCD 램프의 방열성능에 미치는 영향

고동국(Dong Guk Ko),김민수(Min Soo Kim) 대한기계학회 2018 大韓機械學會論文集B Vol.42 No.8

본 연구에서는 UCD 램프의 방열성능에 대한 방열핀의 종횡비와 반경의 영향을 해석적 방법을 이용하여 분석하였으며, 해석에 사용된 격자수와 크기는 각각 11,000개와 0.02 mm이다. 방열핀의 전열면적은 4 ㎟로 일정하게 유지시켰으며, 방열핀의 종횡비는 각각 1.0(기본모델), 1.8, 1.41, 0.56 및 0.29이다. 또한 방열핀의 반경 R은 각각 0.0 mm, 0.3 mm, 0.6 mm, 0.9 mm 및 1.2 mm이다. 핀에 가해진 열의 유속과 시간은 각각 1×105 W/㎡과 0.1 초, 0.2 초, 0.5 초, 1 초, 2 초, 5 초 및 10 초이다. 결과적으로 UCD 램프 방열의 방열성능은 핀의 종횡비와 반경이 각각 1.8과 1.2 mm일 경우 가장 우수하였으며, 기본모델보다 5.7% 상승하였다. In this study, the effects of the aspect ratio and radius of the heat dissipation fin on the heat dissipation performance of a UCD lamp were analyzed using an analytical method. The minimum grid size and number of meshes of the fin used for numerical analysis were 0.02 mm and 11,000, respectively. The heat transfer area of the fin was kept constant at 4 mm². The aspect ratios of the fin were 1.0 (base model), 1.8, 1.41, 0.56, and 0.29, and the respective radii of the fin were R=0.0 mm, 0.3 mm, 0.6 mm, 0.9 mm, and 1.2 mm. The heat flux and heat flux time applied to the fin were 1×105 W/㎡ and 0.1 s, 0.2 s, 0.5 s, 1 s, 2 s, 5 s, and 10 s, respectively. The heat dissipation performance of the UCD lamp was the best when the aspect ratio and radius of the fin were 1.8 and 1.2 mm, respectively, and showed an increase of 5.7% from the base model.

태양광발전 전력변환장치용 GaN-FET의 방열효율 향상을 위한 PCB 방열구조 열해석

이천규(Lee Cheonkyu),정효재(Jeong Hyo Jae) 한국태양에너지학회 2022 한국태양에너지학회 논문집 Vol.42 No.6

In 2021, the solar power generation capacity of South Korea was 14.6 GW, accounting for 71% of the total renewable energy generation capacity. The market for photovoltaic power conversion devices with high efficiency and power density is expanding rapidly in the country. Gallium Nitride (GaN), a compound semiconductor with a wide band gap, can be used under high voltage and current compared to silicon materials, resulting in its wide use in photovoltaic power conversion devices. Excellent heat dissipation performance of GaN-based devices should be achieved due to their significantly high power and efficiency. In this study, the heat dissipation characteristics of a PCB with FR4 (Flame Retardant 4) material composed of various heat dissipation structures for the effective heat dissipation of GaN-FETs for power conversion systems applicable to a 3 kW solar power generation system were investigated using thermal analysis. Part of the heat generated from the GaN-FET was directly dissipated on its surfaces to the external air, and the other part was transferred to the PCB through conduction and then discharged to the external air through convection on the surfaces of the PCB package. Via holes were considered to improve the heat transfer rate of the PCB in the thickness direction, and a heat sink was applied to expand the heat transfer area. In this study, the heat dissipation characteristics were investigated based on four types of heat dissipation structures of the PCB using the ANSYS transient thermal analysis program. The effect of via holes exposed to external air were analyzed using two types of heat dissipation structures. In addition, two other types of heat dissipation structures were analyzed to compare the top and top/bottom cooling of the PCB package. It was observed that the efficiencies of heat dissipation of the via holes that were unexposed to external air and in both the top and bottom cooling cases were more advantageous than that of the exposed holes and the top cooling case, respectively.

자연적 냉각 시스템을 적용한 방송영상용 200W LED 조명장치 제작

이동윤 국제차세대융합기술학회 2022 차세대융합기술학회논문지 Vol.6 No.11

LED의 입력 전원이 증가하면 온도가 지속적으로 상승하는데 냉각 장치가 설치되어 있지 않으면 온도가 증가함에 따라 광속은 급격히 떨어진다. 컨트롤 PCB 케이스는 LED PCB 케이스 후면에서 0°∼90°로 조절되어 양쪽 케이스를 완전히 분리하여 방열효과를 극대화 하였다. 그리고 방열대책에 대한 냉각효과를 높이기 위해 열원 을 분리하고 분리된 부분에 방열판을 부착하였다. 방열판은 열전도를 이용하여 열원의 기판에 히트싱크를 직접 부 착하였으며, LED 보드에 다수의 관통 홀과 열원 판의 케이스에 방열 공을 설계하였다. 열원인 LED 기판과 제어 부를 분리하는 기술을 접목하여 자연적인 냉각효과를 위한 방열 효과를 확인하였다. 그 결과, 위의방열 시스템을 적용한 신뢰성이 높은 영상방송용 LED패널조명의 생산이 가능해졌다. As the input power of the LED increases, the temperature rises continuously, but unless a cooling device is installed, the luminous flux drops sharply as the temperature increases. The control PCB case is adjusted from 0° to 90° from the rear of the LED PCB case to completely separate both cases to maximize the heat dissipation effect. And in order to increase the cooling effect of the heat dissipation measures, the heat source was separated and a heat sink was attached to the separated part. The heat sink is directly attached to the heat source board using heat conduction, and a number of through holes in the LED board and heat sink holes are designed in the case of the heat source board. The heat dissipation effect for the natural cooling effect was confirmed by grafting the technology of separating the control unit from the LED substrate, which is the heat source. As a result, it is possible to produce highly reliable LED panel lighting for video broadcasting by applying the above heat dissipation system.

회로 안정화 부품의 수명예측을 위한 정밀 발열량 산정 기법 개발

김재중(Kim Jaejung),장석원(Chang Seogwon) 대한기계학회 2005 대한기계학회 춘추학술대회 Vol.2005 No.5

Transistor and Regulator I.C which are usally used in the power supply circuit of electronic equipment play an important role in circuit safety. In the case of high heat dissipation chips, they should be operated within the temperature limit. So various heat sinks are used for cooling. Unnecessarily big sized heat sink is used frequently because of miscalculations of heat dissipation of chips. Therefore, this paper has suggested the exact estimation method of heat dissipation for various chips in the circuit. The developed method shows that the heat dissipation is a function of heat sink temperature and ambient temperature. Also, the function is related to the temperature difference from heat sink temperature and ambient temperature. Additionally, the heat dissipation estimation program is in good agreement with the measurement.

휴대용 SSD 외장 하드드라이브 발열문제 개선을 위한 디자인개발 연구

권민성 ( Kwon Min Sung ) 한국기초조형학회 2018 기초조형학연구 Vol.19 No.1

기술의 발전에 따라 전자기기의 크기는 점차 소형화 되고 전자정보의 처리 속도는 지속적으로 향상되고 있다. 이에 따라서 전력을 사용하는 전자기기 성능의 발전은 발열문제라는 숙제를 안겨주었다. 이에 따라 열을 발생하는 전자부품을 담고 있는 제품 용기(product enclosure)를 디자인하는 과정에서부터 방열기능 적용이 구상되어야 한다. 특히 SSD기술이 적용된 초소형 대용량 플레시 메모리를 사용하는 휴대용 외장 하드드라이브의 경우 발열문제 해결이 제품 개발 시 고려해야 할 핵심과제이다. 본 연구는 M.2 SSD를 사용하는 휴대용 외장 하드드라이브의 발열문제 해결에 적합한 디자인 개발을 목적으로 한다. 이를 위해서 발열의 위치와 방열 원리 파악을 위한 모의 실험을 진행한다. 첫째, 기존 제품들 중 경쟁모델을 선정하여 제품 내부의 전자부품 별 온도변화와 차이를 실험을 통하여 측정한다. 둘째, 선별된 3가지 방열방식으로 모의실험을 진행한다. 각 전자부품들과 제품용기의 외곽면 온도 변화를 측정한다. 셋째, 측정된 값과 사용성을 바탕으로 휴대용 제품의 방열에 적합한 방법과 재료를 선정하여 제품디자인 개발 요소로 활용한다. 본 연구의 실험을 통하여 방열에 적합한 디자인요소를 사전에 선별하고자 한다. 선별된 내용들은 이후에 진행될 제품디자인 개발 과정에 효과적으로 활용될 수 있을 것이다. 무엇보다도 발열문제로 인한 제품의 성능저하 문제해결과 사용자의 제품 사용경험 향상을 위한 제품디자인 개발 과정에 적용할 수 있는 디자인요소 발굴에 큰 의미가 있다. 이번 연구를 통하여 정리된 디자인 방안을 토대로 향후 진행될 차세대 휴대용 SSD 외장 하드드라이브 디자인개발에 활용할 것이다. With the development of technology, the size of electronic devices is becoming smaller, and the processing speed continuously faster. The improvement of electronic devices has thus brought about the thermal issue which should be resolved from the industrial design process. Concerning the small external hard disk SSD technology, the problem of thermal has become a key process to be solved in product development. The purpose of this study is to develop a design that minimizes the heating problem of external hard drives using M.2 SSD. Simulations are carried out to understand the location of thermal, and the principle of heat dissipation. First, the competitive model among the existing products is selected, the temperature changed, and the difference of the electronic parts inside the product measured through experiments. Second, the simulation is conducted using three heat dissipation methods. Measure the temperature variation of the outer surface of product container and each electronic component. Third, based on the measured values, the most efficient heat dissipation method and materials are selected and utilized as a design elements for M.2 SSD external hard drive. Based on the results obtained through the simulation, it is beneficial to eliminate non-heat dissipating elements. Above all, it has great significance in finding and applying design elements in order to solve problems of product degradation caused by thermal problem and to improve users' product use experience. Based on the results of this study, I will use it to develop next generation portable SSD external hard drive design.

고 용융점 소재의 압출적층성형을 위한 우수한 방열특성을 갖는 3차원 프린터 nozzle부 기구설계

김완진(Wan-Chin Kim),이상욱(Sang-Wook Lee) 한국전자통신학회 2020 한국전자통신학회 논문지 Vol.15 No.2

300도 이상의 높은 용융점을 갖는 소위 엔지니어링 플라스틱은 기구적인 강성과 내화학성 및 마찰 및 마모성능이 우수하여 여러 산업에서 금속을 대체하는 소재로 각광받고 있다. 본 연구에서는 용융적층모델링 공법을 기반으로 하는 3D 프린터에서 높은 용융점을 갖는 엔지니어링 플라스틱을 조형할 수 있도록 방열특성이 우수한 3D 프린터 nozzle부의 구조를 설계하고 이를 해석적으로 검증하였다. 높은 온도로 가열되는 heat block과 필라멘트가 이송되는 nozzle상부 간의 단열 및 신속한 냉각을 위하여, 열전도계수가 낮은 열차단부(heat brake부)를 2중으로 구성하였고, 열차단부에 생성되는 열이 냉각핀을 통해 대기에 의해 냉각되는 구조를 적용하였다. 개선된 nozzle부 구조설계를 통해 종래 3D 프린터의 BCnozzle과 비교할 때, heat sink부에서의 온도를 50% 가량 낮출 수 있었으며, heat block에 직접적으로 연결된 heat brake부 최종단의 정상상태 온도를 14% 가량 낮출 수 있었다. Since the engineering plastics having a melting point of higher than 300 degrees have a high mechanical rigidity, chemical resistance, friction and abrasion performance, those are being highlighted as metal replacement materials in various industries. In this study, 3D printer nozzle with excellent heat dissipation characteristics are designed and analytically verified to form engineering plastics with high melting points in 3D printers based on the melt-lamination modeling method. In order to insulate between the heat block heated to a melting point of filament material and the upper part of the nozzle where the filament is transferred, the heat brake part with low thermal conductivity was designed to have two separate parts, and a cooling fin structure is further applied to the heat brake part to lower steady-state temperature by air convection. Optimized structural design on FDM nozzle part reduces the temperature at the heat sink and at the end part of heat brake by 50% and 14% respectively, compared to the conventional BCnozzle structure.

방열소재로의 응용을 위한 고분자 복합소재 내 이방성 필러 구조 제어 연구동향

민성배 ( Seong-bae Min ),김채빈 ( Chae Bin Kim ) 한국복합재료학회 2022 Composites research Vol.35 No.6

전자 기기의 발달에 따라 발생하는 발열 문제를 해결하기 위해 높은 열전도도를 갖는 방열소재의 개발이 필요하다. 고분자 복합소재는 고분자의 장점과 열전도성 필러의 장점을 동시에 지녀 경량 방열소재로 각광받고 있다. 하지만, 산업적으로 요구되는 열전도도를 달성하기 위해서는 볼륨비로 60 이상의 고함량의 필러 충진이 요구되므로 최근에는 필러의 구조 제어를 통해 비교적 저함량의 필러 충진으로도 열 전달 경로를 최적화할 수 있는 연구들이 진행되고 있다. 본 리뷰에서는 고분자 복합소재 내 열전도성 이방성 필러의 구조를 제어해 비교적 적은 필러 함량으로 고열전도성 방열소재를 제작하는 다양한 전략을 소개하고자 한다. Efficient heat dissipation in current electronics is crucial to ensure the best performance and lifespan of the devices along with the users’ safety. Materials with high thermal conductivity are often used to dissipate the generated heat from the electronics to the surroundings. For this purpose, polymer composites have been attracted much attention as they possess advantages rooted from both polymer matrix and thermally conductive filler. In order to meet the thermal conductivity required by relevant industries, composites with high filler loadings (i.e., >60 vol%) have been fabricated. At such high filler loadings, however, composites lose benefits originated from the polymer matrix. To achieve high thermal conductivity at a relatively low filler loading, therefore, constructing the heat conduction pathway by controlling filler structure within the composites may represent a judicious strategy. To this end, this review introduces several recent approaches to manufacturing heat dissipating materials with high thermal conductivity by manipulating thermally conductive filler structures in polymer composites.

적층형 디지털송수신모듈의 방열특성 분석

윤기철,김상운,허재훈,곽노진,김찬홍 한국군사과학기술학회 2019 한국군사과학기술학회지 Vol.22 No.2

A Digital Transmitter/Receiver Module(DTRM), which is an essential part in active phased-array radar systems, generates a high heat density, and needs to be properly cooled for stable operation. A tile-type DTRM that is a stacking structure of multi-layer components was modeled with simplification and heat dissipation characteristics of the DTRM model were studied using computational fluid dynamics(CFD) simulations. Most of the heat was dissipated by the heat conduction through the cold plate, but the heat transfer by the forced convection on top of the DTRM also was found to play an important role in the thermal management. Under the given conjugated heat transfer environment, the DTRM was confirmed to secure a stable operating temperature range.

방열핀 형상이 UCD램프의 방열성능에 미치는 영향

고동국(Dong Guk Ko),김민수(Min Soo Kim) 대한기계학회 2017 대한기계학회 춘추학술대회 Vol.2017 No.11

In this study, we propose a method to maximize the heat dissipation performance of a UCD lamp that realizes an 8-wavelength spectrum with sunlight characteristics by using mixed metal and special xenon gas. The aspect ratio and radius of fin were analyzed by analytical method. The minimum mesh size used for the heat dissipation fin was 0.02 mm and the number of mesh was approximately 11,000. In order to understand the effect of the aspect ratio and the radius, the heat transfer area of the fin was kept constant at 4 mm². The fin had an aspect ratio of 1.00(2.00 mm: 2.00 mm(basic model)), 1.41(1.70 mm: 2.40 mm), 1.80(1.50 mm: 2.70 mm), 0.56(2.40 mm: 1.70 mm), and 0.29(2.70 mm: 1.50 mm), respectively. The radius of fin was 0 mm, 0.3 mm, 0.6 mm, 0.9 mm and 1.2 mm, respectively. The heat flux and the heat flux time applied to the fin were 1×10<SUP>5</SUP> W/㎡ and 0.1 second, 0.2 second, 0.5 second, 1 second, 2 seconds, 5 seconds and 10 seconds, respectively. The heat dissipation performance of the UCD lamp was the best when the aspect ratio and radius of the fin were 1.8 and R=1.2 mm.

방열구조에 따른 PCB 방열 특성의 수치해석적 연구

정효재(Hyo Jae Jeong),곽봉우(Bongwoo Kwak),김명복(Myungbok Kim),차동안(Dong An Cha) 대한기계학회 2021 대한기계학회 춘추학술대회 Vol.2021 No.11

Heat generation of chip is recently increasing due to high performance and miniaturization trend of electronic devices, while the thickness and area of the devices are limited. When heat is not released quickly from the chip attached to the printed circuit board (PCB), the temperature of chip will continue to rise, resulting in poor performance and durability. Therefore, it is important to design heat dissipation of PCBs to effectively release heat from chip. Heat from the chip is transferred to the PCB through conduction, and discharged from the PCB and the chips surface to the outside air through convection. In this study, two structure of heatsinks were applied for effective cooling of heat generated from a gallium nitride field effect transistor (GaN-FET), and the heat dissipation characteristics were analyzed according to each heatsink structure using numerical analysis.