• Journal of Advanced Marine Engineering and Technology
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• 제28권6호
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• pp.962-971
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• 2004

This paper has dealt with thermo-physical properties of microencapsulated phase change material slurry as a latent heat storage material having a low melting point. The measured results of the thermo-physical properties of the test microencapsulated phase change material slurry, those are, density, specific heat, thermal conductivity and viscosity, were discussed for the temperature region of solid and liquid phases of the dispersion material (paraffin). The measurements of these properties of microencapsulated phase change material slurry have been carried out by using a specific-gravity meter, a water calorimeter, a differential scanning calorimeter(DSC), a transient hot wire method and rotating type viscometer, respectively. It was clarified that the additional properties law could be applied to the estimation of the density and specific heat of microencapsulated phase change material slurry and also the Euckens equation could be applied to the estimation of the thermal conductivity of this slurry.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2003년도 춘계학술발표대회 논문집
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• pp.53-56
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• 2003

The objective of this research is to investigate the thermal behavior of microencapsulated phase-change materials(MEPCM), and a shell of melamine-formaldehyde. These PCM materials were tested using DSC and thermal data station. Fabrics with enhanced thermal properties were prepared by padding the fabrics with the microcapsules containing PCM and acryl binder. The rate of temperature increase was significantly decreased as the amount of MEPCM added on the surface of the fabrics increased.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 가을 학술논문 발표대회
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• pp.42-43
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• 2020

Lauric acid (LA) which is also known as dodecanoic acid has been selected as the phase change material (PCM) owing to eco-friendly in nature. A systematic study has been conducted for encapsulation of LA (core) with silicon dioxide (SiO2) as shell material. Different core-shell ratio was chosen to microencapsulate the LA with 10 ml of tetraethyl orthosilicate (TEOS) as the precursor solution for the formation of SiO2. The synthesis of microencapsulated LA was carried out at 2.5 pH of precursor solution. The synthesized microencapsulated LA are characterized by Fourier transform infrared spectroscope (FT-IR) and X-Ray Diffraction (XRD) which confirmed the presence of SiO2 shell on the surface of LA.

• 한국염색가공학회지
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• 제19권1호
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• pp.37-44
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• 2007

In this study, for textile use, the octadecane of phase change materials(PCM) was encapsulated in several micro-diameter shell which prevents leakage of the material during its liquid phase. Microencapsulated PCM(PM) was prepared with the different weight ratio of core material to wall material and by interfacial polymerization methods using polyurea as shell material. Phase stability for O/W emulsion of PCM and PVA aq. (PE) was evaluated by Turbiscan Lab. The capsule formation win identified using FT-IR. Physical properties of microcapsules including diameter, particle distribution, morphology were investigated. Thermal transport properties of suede treated with PM(SPM) were determined by KES-F7 system.

• 설비공학논문집
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• 제11권4호
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• pp.549-559
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• 1999

An experimental study was peformed to measure the viscosity of microencapsulated PCM slurries as the functions of its concentration and temperature, and also influence to its fluid dynamics. For the viscosity measurement, a rotary type viscometer, which was equipped with temperature control system, was adopted. The slurry was mixed with water and Sodium Lauryl Sulphate as a surfactant by which its suspended particles were dispersed well without the segregation of particles during the experiment. The viscosity was increased as the concentration of MicroPCM particle added. The surfactant increased 5% of the viscosity over the working fluid without particles. Experiments were proceeded by changing parameters such as PCM particles'concentration as well as the temperature of working fluid. As a result, a model to the functions of temperature for the working fluid and its particle concentration is proposed. The proposed model, for which its standard deviation shows 0.8068, is agreed well with the reference's data. The pressure drop was measured by U-tube manometer, and then the friction factor was obtained. It was noted that the pressure drop was not influenced by the state of PCM phase, that is solid or liquid in its core materials at their same concentration. On the other hand, it was described that the pressure drop of the slurry was much increased over the working fluid without particles. A friction factor was placed on a straight line in all working fluids of the laminar flow regardless of existing particles as we expected.

• 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)

• KIEAE Journal
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• 제12권4호
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• pp.97-104
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• 2012

A phase-change material is a substance with a high heat of fusion which, melting and freezing at a certain temperature, is capable of storing and releasing large amounts of energy. Heat is absorbed or released when the material changes from solid to liquid. Therefore, PCMs are classified as latent heat storage (LHS) units. The purpose of this study is to analyze PCM wallboard design parameters using dynamic energy simulation. Among the factors of PCM, melting temperature, latent heat, phase change range, thermal conductivity are very important element to maximize thermal energy storage. In order to analyze these factors, EnergyPlus which is building energy simulation provided by department of energy from the U.S is used. heat balance algorithm of energy simulation is conduction finite difference and enthalpy-temperature function is used for analyzing latent heat of PCM. The results show that in the case of melting temperature, the thermal energy storage could be improved when the melting temperature is equal to indoor surface temperature. It seems that when the phase change range is wide, PCM can store heat at a wide temperature, but the performance of heat storage is languished.

• 설비공학논문집
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• 제12권9호
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• pp.860-869
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• 2000

The thermal conductivity and density of slurries entrained with the particles of Micro-PCM are measured with respect to its temperatures as well as concentrations. For the thermal conductivity of slurries, a device made from P.A. Hilton (Model No. H470) is adopted. There is a well-scaled 0.3 mm gap between shells into which the slurry is injected. The temperatures of the slurry are changed to $5~25^{\circ}C$ , for which it is controled by the supplied voltage and cooling water circulated around the outer shell. The concentrations of Micro-PCM slurries are varied from 5 wt% to 50 wt%. Some general equations such as Maxwell's equation, are evaluated for their applicability with Micro-PCM slurry. As a result, it happens to be some 20% discrepancy between the experiment and the applied equations. The density measurements of Micro-PCM slurry to its temperature and concentration are peformed by hydrometer. For the experiment, tetradecane encapsulated slurry (($t_m≒6^{\circ}C$) and a mixed wax ($t_m≒50^{\circ}C$) are tested. The temperature changes of tetradecane are applied for $0^{\circ}C\;to\;$20^{\circ}C$and a mixed wax for $20^{\circ}C\;to\;$60^{\circ}C$ and its concentrations are changed from 5 wt% to 30 wt%. The results are compared with a general equation and the referenced data. For the conclusion, the experimental result and a general equation are well agreed.

• 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.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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• pp.475-479
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• 2012

Thermal energy storage (TES) systems using Microencapsulated phase change material (MPCM) have been recognized as one of the most advanced energy technologies in enhancing the energy efficiency and sustainability of buildings. We examined a way to incorporate MPCMs with building materials through application for wood-based flooring. Wood-based flooring is commonly used for floor finish materials of residential buildings in Korea. However, wood-based flooring has not performed the characteristic of heat storage. This study is aimed at manufacturing high thermal efficiency wood flooring by increasing its heat storage using MPCM. As a result, this study confirmed that MPCM is dispersed well in adhesive through the scanning electron microscopy analysis. From the differential scanning calorimetry analysis, it can be confirmed that this composite has the characteristic of a thermal energy storage material. Also, we analyzed how this composition was formed by physical combination through the Fourier transform infrared analysis. Also, we confirmed the bonding strength of the material by using the universal testing machine.