• Title/Summary/Keyword: Heat Insulation

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Effect of External Thermal Insulation Composite System with a Non-combustible Calcium Silicate Based Mineral on The Mitigation for Reducing Fast Spread of Flame (불연성 무기 단열재를 화재확산 방지구조로 적용한 외단열 마감시스템의 화재성능)

  • Lee, Jong-Chan;Park, Jong-Chul;Song, Hun
    • Journal of the Korea Institute of Building Construction
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    • v.16 no.5
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    • pp.397-403
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    • 2016
  • As a building energy saving standard strengthened, The number of building installed external thermal insulation composite system(ETICS) using EPS insulation increased. But frequent fire accident in the buildings installed EIFS using EPS led to strengthening of building fire safety regulation. This study is for fire property of EPS ETICS reinforced with noncombustible calcium silicate-based mineral insulation as a fire spread prevention structure(FSPS). Fire test for large scale wall by ISO 13785-2 was applied and results showed EPS EIFS with FSPS got 3~8 times superior fire safety than normal EIFS by visual investigation. Temperature and heat flux measurement results, which data of upside of specimen were lower than downside, also supported fire safety of EIFS with FSPS.

Study of Thermal Decomposition of Kevlar/EPDM (Kevlar/EPDM 고무계 내열재의 열반응 연구)

  • Kim, Yun-Chul;Jung, Sang-Ki;Kang, Yoon-Goo;Lee, Seung-Goo
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2010.11a
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    • pp.257-260
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    • 2010
  • The purpose of this paper is to introduce a method to predict the case thermal insulation charred and erosion thickness as a function of the exposure time to combustion gases and in solid rocket motors. The sizing of the insulator requires a good estimation of the thermal and mechanical loads at the wall. The method is particularly suitable for internal insulation areas subjected to high radiative, convective heat fluxes and $Al_2O_3$ slag pool. The mathematical approach and lab-scale experiment were intentionally simplified in order to obtain some simple and rapid relationships particularly useful for trade-off studies and thermal insulation preliminary design. The method was utilized to compute the charred and erosion thicknesses of the insulation on the aft chamber domes. A comparison between theoretical and experimental insulator char thicknesses of the motor insulation is reported, indicating the applicability of the predictive method employed.

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Analysis of DC insulation and properties of epoxy/ceramic composites with nanosized ZnO/TiO2 fillers

  • Kwon, Jung-Hun;Kim, Yu-Min;Kang, Seong-Hwa;Kim, Pyung-Jung;Jung, Jong-Hoon;Lim, Kee-Joe
    • Journal of Ceramic Processing Research
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    • v.13 no.spc2
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    • pp.332-335
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    • 2012
  • A molded transformer is maintenance-free, which makes it unnecessary to replace the insulating material, like in an oil-filled transformer, because the epoxy, which is a molded insulating resin, does not suffer variations in its insulating performance for heat cycles over a long time, as compared to insulating oil. In spite of these advantages, a molded transformer may still be accessed by the user, which is not good in regards to reliability or noise compared to the oil transformers. In particular, a distrust exists regarding reliability due to the long-term insulating performance. These properties have been studied in regards to the improvement of epoxy composites and molded transformer insulation. There have nevertheless been insufficient investigations into the insulation properties of epoxy composites. In this study, it is a researching of the epoxy for insulating material. In order to prepare the specimens, a main resin, a hardener, an accelerator, and a nano/micro filler were used. Varying amounts of TiO2 and ZnO nano fillers were added to the epoxy mixture along with a fixed amount of micro silica. This paper presents the DC insulation breakdown test, thermal expansion coefficient, and thermal conductivity results for the manufactured specimens. From these results, it has been found that the insulating performance of nano/micro epoxy composites is improved as compared to plain molded transformer insulation, and that nano/micro epoxy composites contribute to the reliability and compactness of molded transformers.

Advanced Heat Transfer Analysis Model of LNG Storage Tank (LNG 저장탱크의 개선된 온도해석 모델)

  • 전세진;정철헌;진병무;김성운
    • Proceedings of the Korea Concrete Institute Conference
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    • 2003.05a
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    • pp.115-120
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    • 2003
  • Several methodologies were devised to reasonably predict the temperature boundary conditions of inner face of the concrete outer tank so as to set up heat transfer analysis model of the full containment above-ground LNG storage tank. In this model, outer tank is solely taken into account and the beneficial effect of suspended deck and insulation layers on the temperature distribution of outer tank is separately formulated according to the proposed procedures. More effective design of the insulations can be achieved when the proposed simple schemes are used in the preliminary stage.

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최적 열전달계수를 이용한 단열기준산출

  • Lee, Jin-Won;Lee, Jong-Won
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.8 no.2
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    • pp.95-100
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    • 1979
  • Optlmum overall heat transmission coefficient for residential buildings is calculated as a function of building parameter, area/volume. Equivalent heat transmission coefficient and equivalence factor are introduced and optimized with respect to annual cost including fuel cost , insulation cost and equipment cost Comparison with recent standard of West Germany shows similarity of the result.

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Thermal Effect of the Transparent Insulated Opaque Envelopes (투명 단열외피의 열적성능에 관한 연구)

  • Kim, Se-Hwan;Lee, Sung
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.4 no.4
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    • pp.19-24
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    • 2004
  • The thermal effect of a transparent insulated opake wall with solar energy was investigated theoretically. The heat gain through transparent insulated opake wall was studied for relative simple conditions. The stationary heat transport effect was studied for layer which is built on the opake wall. This study shows that a relative low solar radiation intensity causes a great heat reduction through the transparent insulated opake wall. Because the transparent insulation layer is mostly transparent to solar radiation, it is opaque to heat radiation.

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Reducing effect for Hydration Heat of High-Strength Concrete according to Admixture Types and Replacement Ratios (혼화재 종류 및 대체율에 따른 고강도콘크리트의 수화열 저감 효과)

  • 유범재;김용로;최세진;김상윤;김상규;김무한
    • Proceedings of the Korea Concrete Institute Conference
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    • 2001.11a
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    • pp.409-414
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    • 2001
  • The hydration of cement paste occurs when the cement is mixed with water. During the hydration, hydration heat causes the thermal stress depending on the size of concrete and the cement content. Especially in the high-strength concrete, we must give care to the concrete due to its large cement content. In this study, conduction calorimeter and concrete insulation hydration heat meter were used to investigate the hydration heat characteristics of cement and concrete. To reduce hydration heat of high-strength concrete, several types of replacement of fly-ash and blast-furnace slag powder were used in this experiment.

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A Study on Thermal Performance of the Heat Recovery Ventilator used Window (창호적용 배열회수 환기유닛의 열성능평가 연구)

  • Jang, Cheol-Yong;Cho, Soo;Sung, Uk-Joo;Lee, Jin-Sung
    • 한국태양에너지학회:학술대회논문집
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    • 2008.04a
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    • pp.129-134
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    • 2008
  • Generally the window of the building is an objective of mining and having a distant view and also for a circulation it will can open and shut because becomes the structure insulation, the meat detailed drawing it does a very difficult portion, it is. And, recently the use of heat recovery ventilator has increased rapidly for improvement of air Quality and energy saving in building. But, the high efficient heat exchange will be more increasable than water vapors which were only occurred residential active. Purpose of this study is measurement of thermal performance about heat-recovery system integrated window. The result of the window thermal resistance is 1.80 $W/m^2K$ by KS F 2278. Air tightness is 5.96 m3/m2h at 4 Pa by KS F 2292.

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Effectiveness of a Heat Transfer Characteristics of an Auxiliary Chamber for Performance of an Air Spring (보조용기의 열전달특성이 공기스프링의 성능에 미치는 영향)

  • Jang, Ji-Seong
    • Journal of Power System Engineering
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    • v.17 no.2
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    • pp.121-127
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    • 2013
  • The air spring is used widely because of the easy change of spring constant, and, a superior vibration and shock insulation performance. Among the apparatus using the merits of that, the air spring connected an auxiliary chamber has been developed and used as a component of suspension system for an automobile and a railroad car. The purpose of this study is to suggest a design method reflecting heat transfer effect for an air spring system connected auxiliary chamber. In order to do so, this study investigates change of reaction force along with variations in heat transfer coefficient, and, analyzes an effectiveness of a heat transfer characteristics of an auxiliary chamber for external force attenuation characteristics and impedance characteristics of an air spring connected an auxiliary chamber.

Effect oh Heat Treatment on Breakdown Properties in the Joint Interface of Power Cables (전력케이블 절연접속계면의 절연파괴 특성에 미치는 열처리 효과)

  • 이창종;김진수;박강식;한상옥
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.11 no.7
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    • pp.502-507
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    • 1998
  • The purpose of this study is to investigate the breakdown properties in joint interface of power cables with heat treatment. The specimens have the structure of XLPE/EPDM interface like the joint of distribution power cable. The breakdown characteristics of the SLPE/EPDM joint were studied with crosslinking by=products. AC breakdown voltages were measured with heat treatment time and interfacial materials and crosslinking by-products as testing factors. This study has shown that crosslinking by-product gases play an important role at the insulation properties of cable joints by heating. The dielectric strength shows the lowest values at 4 hours heat treatment. The AC breakdown strength in the untreated sample was increased with heat treatment time.

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