• Journal of The Korean Society of Agricultural Engineers
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• v.46 no.4
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• pp.39-46
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• 2004

This experiment was carried out to study on the effect of surface coating on thermal insulation of farm structures to improve thermal resistance and reflective effect of solar radiation. Nine different types of experimental specimen were compared in the temperature variations of inside and outside; A, B, C, D. E and F types are box container and G, H and I types are drum container. The size of these containers is $1,500{\times}2,000{\times}2,500$ mm and ${\varphi}$ $280{\times}330$ mm, respectively. Specimen of 3-type box(A, B, C) is galvanized steel sheet of thickness 0.45 mm. D, E and F types are sandwich panel of the thickness 50 mm inserted with urethane, glass wool and polystyrene form, respectively. G, H and I types are paint pot using in general. The surface of A. D, E, F and I types didn't any treatment, B, C and G types were treated with thermal insulation coating on the outside surface(B, G) or the inside and outside surface(C). And H type was treated with water paint coating on the only outside surface. In general, the experimental results showed the following tendencies; In case of A, B and C types. it was found that the thermal insulation effect of types coated with thermal insulation coating was improved remarkably than that of no treatment. And the thermal insulation effect between steel sheet and sandwich panel type was nearly similar There was not a significant difference of thermal insulation effect between thermal insulation coating and water paint coating. In time of drum container filled with rough rice, The difference of heat transfer tendency and temperature variation among surface treatments was nearly similar that of box types of galvanized steel sheet. And there was time lag about 6 hours between the temperature of middle part of rice and that of inside or outside surface.

• Journal of Ceramic Processing Research
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• v.19 no.6
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• pp.450-454
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• 2018

In recent years, thermal insulation coating technology for automotive engine parts has received significant attention as a means of improving the thermal efficiency of automotive engines. One of the characteristics of thermal insulation coatings is their low thermal conductivity, and, materials such as YSZ (Yttria-stabilized zirconia), which have low thermal conductivity, are used for this purpose. This research presents a study of the changes in the microstructure and thermal conductivity of $8YSZ/SiO_2$ multi compositional thermal insulation coating for different compositions, and particle size distributions of suspension, when it is subjected to suspension plasma spraying. To obtain a porous coating structure, the mixing ratio of 8YSZ and $SiO_2$ particles and the particle sizes of the $SiO_2$ were changed. The microstructure, phase formation behavior, porosity and thermal conductivity of the coatings were analyzed. The porosities were found to be 1.2-32.1%, and the thermal conductivities of the coatings were 0.797-0.369 W/mK. The results of the study showed that the microstructures of the coatings were strongly influenced by the particle size distributions, and that the thermal conductivities of the coatings were greatly impacted by the microstructures of the coatings.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.12
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• pp.1147-1152
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• 2013

In this study, the effect of an insulation coating on the start time of a linear region is theoretically investigated when an insulation-coated hot-wire is used for the transient hot-wire method (THWM). For this purpose, important parameters affecting the start time of the linear region are presented from an analytical solution of temperature-rise for an insulation-coated hot-wire. Furthermore, a critical time to ignore the influence of important parameters is studied. The theoretical results indicate that the effect of the insulation coating rapidly disappears with a decrease in the wire radius, coating thickness, thermal diffusivity of insulation material or an increase in the thermal conductivity of the insulation material. The results of this study will be helpful for selecting a proper start time of the linear region for the THWM using insulation-coated hot-wires.

• Steel and Composite Structures
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• v.15 no.1
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• pp.1-14
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• 2013

Predicting the fire resistance of structures has been significantly advanced by full scale fire tests in conjunction with improved understanding of compartmental fire. Despite the progress, application of insulation is still required to parts of structural steelwork to achieve over 60 minutes of fire rating. It is now recognised that uncertainties on insulation properties hinder adaptation of performance based designs for different types of structures. Intumescent coating has recently appeared to be one of most popular insulation types for steel structures, but its design method remains to be confirmed by empirical data, as technical difficulties on the determination of the material properties at elevated temperatures exist. These need to take into account of further physiochemical transitions such as moving boundary and endothermic reaction. The impetus for this research is to investigate the applicability of the conventional differential equation solution which examines the temperature rise on coated steel members by an inorganic intumescent coating, provided that the temperature-dependent thermal/mechanical insulation properties are experimentally defined in lab scale tests.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.9 no.3
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• pp.300-311
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• 1997

A theoretical method was developed to analyze the effect of low-$\varepsilon$ coatings which have influence on thermal performance of vacuum windwo glazing and double pane glazing. The overall heat transfer coefficient(U) value and thermal performance were analyzed by theroretical method on various kins of windows. TRNSYS program was used to analyze total heating and cooling energy consumption on the model building which has various windows. As the result, better thermal insulation can be achieved on the vacuum window glazing than double pane glazing when low-$\varepsilon$ coating was done on the surface of glass. Total heating and cooling energy consumption was almost same on the double pane window glazing but was lessened on the vacuum window glazing when the window size of south direction increased. Therefore, low-$\varepsilon$ coating was very necessary for vacuum window glazing in order to improve thermal insulation performance and efficient energy conservation can be achieved by vacuum window glazing at the real building which has large window.

• Nuclear Engineering and Technology
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• v.38 no.2
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• pp.139-146
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• 2006

An experimental study was performed to evaluate the effects of surface coating and an enhanced insulation structure on the downward facing boiling process and the critical heat flux on the outer surface of a hemispherical vessel. Steady-state boiling tests were conducted in the Subscale Boundary Layer Boiling (SBLB) facility using an enhanced vessel/insulation design for the cases with and without vessel coatings. Based on the boiling data, CHF correlations were obtained for both plain and coated vessels. It was found that the nucleate boiling rates and the local CHF limits for the case with micro-porous layer coating were consistently higher than those values for a plain vessel at the same angular location. The enhancement in the local CHF limits and nucleate boiling rates was mainly due to the micro-porous layer coating that increased the local liquid supply rate toward the vaporization sites on the vessel surface. For the case with thermal insulation, the local CHF limit tended to increase from the bottom center at first, then decrease toward the minimum gap location, and finally increase toward the equator. This non-monotonic behavior, which differed significantly from the case without thermal insulation, was evidently due to the local variation of the two-phase motions in the annular channel between the test vessel and the insulation structure.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.275-275
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• 2010

나노하이브리드 방법으로 제조된 변성 폴리이드계 나노하이브리드 절연코팅의 표면 내열특성을 비교 분석하였다. 최근 절연코팅의 사용환경이 열적내구성을 높게 요구하는 경향이 크다. 따라서 이러한 환경에 맞는 절연성과 열적내구성을 구현하기 위해서는 열적내구성이 우수한 세라믹 일자를 수지에 분산시켜 그 성능을 개선할 필요가 있다. 본 논문에서는 나노 하이브리드 방법으로 제조된 변성 폴리이드계 나노하이브리드 절연코팅의 표면 내열특성을 비교 분석하였다.

• Journal of the Korean Applied Science and Technology
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• v.29 no.1
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• pp.141-148
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• 2012

In this study, the composite coating materials with improved thermal insulation property were prepared by incorporating the hydrophobic silica aerogel. The surface modification of silica aerogel was performed to obtain UV curable urethane acrylate hybrid coating sols with good compatibility by using surfactant(Brij 56). The polycarbonate substrates were coated by the prepared composites and cured under UV radiation. The incorporation of aerogel with only 10 vol% of content resulted in remarkable improvement by about 28% in the thermal insulation property of the coated film, as compared with substrate. In addition, increasing aerogel content was found to give minor effect on the variation of optical transparency, adhesion, and surface hardness of the coated film.

• Korean Chemical Engineering Research
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• v.50 no.4
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• pp.621-626
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• 2012

In this study, the composite coating materials with improved thermal insulation property were prepared by incorporating the hollow micro-spheres with high heat transfer resistance. The UV curable resin system consisting of hexa aliphatic urethane acrylate (UP118), trimethylolpropane triacrylate (TMPTA), 1,6-hexanediol diacrylate (HDDA), and photoinitiator (Irgacure184) was employed as an organic binder. The glass substrates were coated by the prepared composites via bar coating method and cured under UV radiation. The optical transparency, thermal insulation property, adhesion, and surface hardness of the glass coated with composites containing different type of micro-spheres were investigated. The incorporation of micro-spheres with only 20 vol% of content resulted in remarkable improvement in the thermal insulation property of the coated glass. In addition, the transparent coated glass with light transmittance of about 80% could be obtained when silica micro-sphere (SP) was used as a thermal barrier.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.35-36
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• 2023

Safety management of steel frame members is a very important part to maintain safety and function. However, precise inspection is not possible for steel frame members due to finishing materials and insulation materials, leading to poor inspection. For steel members, an insulating spray coating method is used for high thermal conductivity. The insulation spray method is not only uneconomical, but also has the disadvantage of spoiling the aesthetics. In addition, VOCs are released from paints used in spraying, so a solution is needed. In this study, heating paint was used to improve the disadvantages of the insulation spray coating method and the high thermal conductivity of steel frame members. In addition to this, in order to reduce VOCs generated from the paint, active clay was added to produce a functional exothermic paint, and then the experiment was conducted. As the amount of activated clay increased, the film thickness increased, and the VOCs emission and thermal conductivity decreased.