• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.2
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• pp.189-199
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• 2000

This paper investigates the thermodynamic performance of latent heat thermal energy storage system using two phase change materials(2-PCM system). The thermodynamic merit of using 2-PCM is clear in terms of exergetic efficiency, which is substantially higher than that of 1-PCM system. Optimum phase change temperature to maximize the exergetic efficiency exists for each case. The heat transfer area ratio of high temperature storage unit, X, becomes another important parameter for 2-PCM system if the phase change temperatures of given materials are different from those of optimum conditions. It is a good approximation for X$_{opt}$ to be 0.5 when optimum phase change temperatures are used. Otherwise X$_{opt}$ is determined differently as a function of given phase change temperatures.res.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.272-273
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• 2014

Existing the free-form concrete segments (FCS) mold is produced by state of solid such as steel, wood, Styrofoam that can not be recycled. Using FCS mold result in delay on schedule and decrease of productivity because it consists of irregular curved variety and it requires more time than fixed mold. Thus, FCS mold should be developed which can reduce the costs and also it can be used as semipermanent. The aim of this study is to suggest of flexible mold production process for using the phase change materials(PCM). PCM is maintain that its solid state at low temperature but it changes phase to liquid state by heating. PCM is suitable material for flexible mold due to change of phase in relatively high temperature compare to other phase change materials such as water. Flexible mold is possible that reuse semi-permanently made by PCM. Thus, this study is proposed the process of flexible mold production for using the PCM. The study results will be used as the basic theory for studies on production and installation of FCS.

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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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)

• Proceedings of the Korean Society For Composite Materials Conference
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• 2003.04a
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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.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.6
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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.

• Polymer(Korea)
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• v.34 no.3
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• pp.261-268
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• 2010

Phase change materials based on polypropylene blended with n-eicosane were studied in this paper. In addition, this paper reviews recent studies on the preparation of shape stabilized phase change materials (SSPCM), such as SSPCM from polypropylenes and n-eicosane, their basic properties and possible applications to latent heat storage. The preparation methods used were the melting method and absorption methods. Shape stabilized PCM(SSPCM) prepared for DSC, WAXD, FTIR spectroscopy, ARES, results of the analysis of shape stability heat capacity to improve were identified.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.8 no.4
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• pp.576-582
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• 1996

This work studies qualitative thermal characteristics of PCM cold storage medium container and its surrounding streams. Experimental parameters are initial PCM temperature and cold water flow rate. A mathematical modeling was establised to estimate temperature distribution and the cooling process. We found that the phase-change temperatures of PCM varies from 6 to $8^{\circ}C$ which is constant for other materials and that the dominant heat transfer resistance is that on the container side taking about 3/4 of the total resistance. The one dimensional mathematical model predicts experimental data quit well.

• Transactions of the Korean Society of Automotive Engineers
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• v.4 no.3
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• pp.187-198
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• 1996

In this study, the performance of an automobile heat storage system using PCM is numerically simulated. For the analysis of system performance. The phase-change of the PCM and the transient forced convective heat transfer for the HTF are considered simultaneously as a conjugate problem. The phase-change behavior is effectively analyzed using a concept of thermal resistance. From the correlations of phase change rate and heat transfer due to the variations of flow rate of HTF around PCM, the automobile heat storage system performance is predicted. The present results amy be used as the fundamental information for the design of automobile heat storage system.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.216-217
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• 2014

Optimum finishing position, thickness and phase change temperature of winter and summer season were selected and suitability of finishing materials was evaluated based on temperature measurement of specimens applying the coating material mixed phase change materials(PCM). As a result, when finishing position was interior and finishing thickness of coating material mixed n-Octadecane(28℃ PCM) was 4mm, thermal performance was effective. n-Octadecane in summer season and n-Hexadecane(18℃ PCM) in winter season are indicated effective on energy savings, respectively.

• Textile Coloration and Finishing
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• v.19 no.1 s.92
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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.