• 설비공학논문집
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• 제25권9호
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• pp.477-483
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• 2013

A numerical analysis of solid-liquid phase change was performed on a heat transfer module which consisted of circulating water path (BRINE), heat transfer plate (HTP) and phase change material (PCM) layers, such as high temperature PCM (HPCM, $78{\sim}79^{\circ}C$) and low temperature PCM (LPCM, $28{\sim}29^{\circ}C$). There were five arrangements, consisting of BRINE, HTP, LPCM and HPCM layers in the heat transfer module. The time and heat transfer rate for melting/solidification was compared to their arrangements, against each other. As results, the numerical time without convection was longer than the experimental one for melting/solidification. Moreover, the melting/solidification with the BRINE I-LPCM-BRINE II-HPCM arrangement was faster(10 hours) than the others; HPCM-BRINE-LPCM, BRINE I-HPCM-LPCM-BRINE II one.

• 한국태양에너지학회 논문집
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• 제33권3호
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• pp.9-16
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• 2013

In this research, the effect of a heating system, which is powered by direct solar energy accumulated in phase change material (PCM) as heat storage material installed on the floor surface, on the cooling load was studied. Cooling load of a test building designed for this research was measured with fan coil unit and factors affecting it were also estimated. Experiments were performed with and without PCM installed on the building floor to understand the effect of the PCM on the cooling load. Additionally, to confirm the experiments results, the prediction calculation formula by average outside temperature and integrated solar radiation was composed using multivariate regression model. The results suggested that the heating system with PCM on the floor surface has the potential to shift electric power peak by radiating heat, stored during the daytime in it, at night, not increasing the total cooling load much.

• 한국항공우주학회지
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• 제38권11호
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• pp.1087-1093
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• 2010

열관(HP)과 상변화물질(PCM)을 병렬로 배열한 일체형 위성 열제어 H/W를 제안하였다. HP-PCM 모듈은 제한적인 의미에서 일종의 off-the-shelf 부품으로써, PCM을 위한 별도의 열설계와 형상설계 등을 수행하지 않더라도 기존에 사용하고 있는 HP처럼 크기나 개수 등만을 설계함으로써 온도제어를 달성할 수 있도록 하였다. 주기적인 발열이 있는 부품의 온도제어를 위하여, 제안한 HP-PCM 모듈이 적용된 위성 방열판을 설계하고 상세모델을 수립하여 수치해석을 수행하였다. 각각 PCM이 없는 경우와 PCM을 장입한 경우에 대하여 수치해석을 수행하였으며, 등가평균값의 주기적인 변화에 대한 비교분석을 통하여 PCM의 축열과 방열에 의한 열분산이 매우 효과적임을 확인하였다. HP가 작동하지 않는 경우에 대한 수치해석을 통하여 열전도도가 작은 PCM의 사용한계를 제안한 HP-PCM 모듈을 이용하여 극복할 수 있음을 확인하였다.

• 한국의류학회지
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• 제28권6호
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• pp.767-775
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• 2004

In order to evaluate physiological responses and comfort sensation of the developed thermoregulating textile material, polyester knit fabric was treated with phase change material (PCM) microcapsules by printing. Ten male subjects wearing an experimental best with and without PCMs were seated for 20 minutes, then exercised for 20 minutes, and then seated for 30 minutes in the chamber which was controlled under the temperatures of 20$\pm$1$^{\circ}C$, 50$\pm$5%R.H. The subject's skin temperature, microclimate inside garment and comfort sensation of two experimental bests were compared one another. As a result, the rectal temperature, skin temperature and mean skin temperature were similar in the two groups, and the subjects were not able to perceive the differences in comfort of the two experimental bests. However, the effect of PCM microcapsule could be seen from microclimate temperature and humidity. The microclimate temperature of the PCM garment at chest was significantly higher during exercise. The microclimate humidity of the PCM garment at chest was significantly lower during exercise and rest.

• 태양에너지
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• 제17권2호
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• pp.67-74
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• 1997

잠열 저장물질로서 비조화 축열재인 sodium acetate trihydrate를 사용하여 구형의 PCM 입자를 제조하였다. 비조화 축열재의 단점인 상분리 현상 및 과냉각 현상을 방지하기 위하여 점증제로서 gelatin, 조핵제로서 sodium pyrophosphate decahydrate를 사용하였다. 혼합조성의 용융 PCM을 이용하여 연속적으로 지름이 3-3.5 mm 인 구형 PCM 입자가 제조되었다. 용융 PCM 방출속도가 1.3-1.8 ml/min 인 범위 내에서는 PCM 입자크기가 방출속도에 영향을 받지 않았다. 제조된 PCM 입자의 물성을 측정하기 위하여 DSC, SEM과 XRD를 이용하였다.

• 한국항공우주학회지
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• 제44권10호
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• pp.887-894
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• 2016

고상-액상 상변화물질(PCM, Phase Change Material)을 이용한 위성부품 열제어장치를 설계 및 제작하였으며 열환경시험을 수행함으로써 온도제어 성능을 분석하였다. 설계온도에 부합하는 n-Hexadecane을 PCM으로 채용하였고, 낮은 열전도도를 보완하기 위하여 내부에 전열휜이 장착된 용기를 Al6061로 제작하였다. 위성에 장착하였을 때와 동일한 작동조건을 확보하기 위하여, 부품과 방열판 사이를 열관으로 연결하였으며 열관의 단열부가 관통하도록 PCM 열제어장치를 설치하였다. 동일한 모양과 부피의 열적완충질량(TBM, Thermal Buffer Mass)도 제작하여, 주기적인 가열-냉각 실험을 수행하였다. 실험결과 상변화 잠열에 의한 PCM의 열제어 성능을 확인할 수 있었으며, TBM에 비하여 질량과 보온히터의 소모전력을 절감할 수 있음을 확인하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집B
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• pp.297-303
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• 2000

Natural convection heat transfer have been paid attention because it can be applied to various areas such as cooling of nuclear reactor, heat storing system and so on. Among such applications, the melting process of phase change material(PCM) has been actively studied. However most researches have focused on phase change heat transfer in natural melting. Therefore, In this paper, ultrasonic vibration was adopted to increase the melting rate. In addition, general relationship and corelationship between melting with ultrasonic vibration and melting without ultrasonic vibration have been established during the melting of PCM.

• Elastomers and Composites
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• 제56권2호
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• pp.72-78
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• 2021

A phase-change material (PCM) is a material that has the ability to delay heat transfer by absorbing heat from its environment or releasing heat to its environment while its phase changes from solid to liquid or liquid to solid at a specific temperature. As it is applied, it can contribute to environmental conservation such as energy savings and carbon dioxide emission reduction. In order for a PCM to store and release heat, the volume change during its phase transition should be large, and thus a phase transition space is required. When a PCM is used as a polymer additive, it is confined within the polymer, and there is no phase transition space; thus, its ability to absorb and release heat is significantly reduced. Therefore, in this study, porous silica was used to provide EVA/PCM compounds with sufficient space for their phase transition, and to improve the compatibility between the EVA and PCM, modified silica is used: surface-modified 5 wt% silica with 3-methacryloxypropyltrimethoxysilane. The compound was prepared and compared with the silica compound. The presence or absence of the modified silica surface modification was confirmed using Fourier-transform infrared spectroscopy and thermogravimetric analysis, the heat capacity of the compound was evaluated based on a differential scanning calorimetry analysis, and its mechanical strength and morphology were determined using scanning electron microscopy.

• 대한기계학회논문집B
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• 제29권11호
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• pp.1173-1181
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• 2005

The cooling effect of a mobile phone using PCM(Phase Change Material) module has been numerically investigated. A transient three-dimensional numerical analysis of heat and fluid flow with natural convection is performed in this study. Governing conservation equations for mass, momentum and energy are solved by an implicit finite volume method. An enthalpy-porosity technique has been used for modeling of the melting process. Two different ways of placing the PCM module are considered. One is to place a PCM module between the substrate and battery pack, and the other is to place a PCM module between MCM(multichip module) and battery pack. Three different types of PCMs are used to predict the performance of PCM. The results show that passive cooling with PCM can reduce the temperature rise and the effect of natural convection in PCM module considered in this study is negligible.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2001년도 가을 학술발표회 논문집
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• pp.397-400
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• 2001

상변화물질(phase change material, PCM)은 외부온도변화에 따른 상변화에 따라 흡열과 방열성을 반복적으로 나타내는 물질로서 건축, 우주항공분야 등에서 열전달매체나 열조절시스템에 응용되어 왔다. 이러한 PCM의 응용방법은 PCM을 미세한 입자(직경이 약 100$\mu\textrm{m}$)로 만들어 직접 운반유체 속에 분산시켜 이용하거나, PCM을 심물질로 하는 마이크로캡슐을 제조하여 이용하는 방법을 들 수 있다. (중략)