• The Journal of the Korea Contents Association
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• v.15 no.12
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• pp.604-611
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• 2015

When the moisture in concrete member evaporates by high temperature, the evaporation heat which absorbs surrounding temperature occurs. The incremental rate of the internal temperature in concrete is reduced due to the evaporation heat in spite of continuously increasing external temperature. Therefore, this paper has proposed the evaluation algorithm for predicting the internal temperature of concrete members considering the evaporation heat under the high temperature. Finite element method is employed to facilitate thermal analysis for any position of member. To demonstrate the validity of this numerical procedure, the prediction by the proposed algorithm is compared with the test results of other researchers. The proposed algorithm shows a good agreement with the experimental results including the phenomenon that temperature is lost by the evaporation heat.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.4A
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• pp.355-363
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• 2009

When water inside the concrete member evaporates by high temperature, the evaporation heat which absorbs surrounding temperature occurs. The rate of increment of the internal temperature in concrete is reduced due to the evaporation heat in spite of continuously increasing external temperature. In this paper, the prediction method of internal temperature of concrete members considering the evaporation heat under the high temperature is presented. Finite element method is employed to facilitate thermal analysis for any position of member. And the thermal characteristics models of high strength concrete affected by high temperature are proposed. To demonstrate the validity of this numerical procedure, the prediction by the proposed algorithm is compared with the test results of other researchers. The proposed algorithm shows a good agreement with the experimental results including the phenomenon that temperature is lost by the evaporation heat.

• Electric Engineers Magazine
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• v.246 no.2
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• pp.30-33
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• 2003

증발성 액체소화제 할로겐화 탄화수소는 기화되기 쉬운 액체 또는 기체이고 억제작용, 희석효과, 기화열에 의한 냉각 등 3가지의 작용을 한다. 액상인 것은 목재화재에도 다소 쓰이고 있지만 가연성약제의 소화에 쓰일 뿐만 아니라 전기의 불량도체이므로 전기화재에 대한 적응성이 있다.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1997.11a
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• pp.14-19
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• 1997

식물의 광반응은 광질과 광강도에 따라 상이하며, 광은 열을 동반하게 되므로 광만을 분리하여 생각할 수 없다. 즉, 광은 식물체의 체온과 엽온을 높이고, 잎의 수증기 장력을 증가시켜 증산을 촉진하므로 기화열을 발생하는 원동력이 되기도 한다. 따라서 광은 잎속의 수분이나 기공개도 등에 영향을 주기 때문에 광합성속도에 간접적인 영향을 미치기도 한다. (중략)

• Journal of Energy Engineering
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• v.11 no.2
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• pp.178-185
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• 2002

The object of this paper is to investigate the effects of early fuel evaporators on cold driveability of gasoline passenger cars. Experiment has been carried out for the assessment cold start performance and cold driveability. And fuel consumption rate, emission and cylinder pressure were measured. On the base of combustion pressure of cylinder, rate of heat release, cumulative heat release amount and burned mass fraction are evaluated. The results show that fuel consumption rate is increased by 17.7%, monoxide and hydrocarbon were reduced by 23% and by 45% respectively, fluctuations of indicated mean effective pressure and maximum combustion pressure were increased by 4∼6%, fuel consumption rate per power was improved by 0.2∼2.3%. These are caused by the fact maximum heat release period and main combustion period are getting short.

• Journal of the Korean Institute of Gas
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• v.11 no.1 s.34
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• pp.46-50
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• 2007

The metering systems in LPG vaporizers have been frequently exposed to severe conditions and resulted in many problems such as gauge malfunctioning and rupturing if the check-floaters fail to stop liquid outflow when the heat supply for the vaporization of LPG is interrupted. Therefore, to analysis the vaporizer system we carried out the vaporizer performance test and float bulb test by newly devised test equipments. Consequently, we determined the specific gravity of the float bulb and reasonable operating temperature ranges for the LPG and heating waters.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.415-415
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• 2012

ICP (RF) 열 플라즈마 분말 합성법은 초고온 열플라즈마(~10,000 K) 속으로 원료물질을 투입한 뒤, 용융, 기화 및 재합성의 과정을 거쳐 초미분(<1 ${\mu}s$)을 합성하는 방법으로 고출력 시스템의 경우 고온/고 엔탈피 열 유동을 통한 고융점 및 저융점 복합물질의 동시 기화에 의한 물질 조성이 제어된 나노 복합체의 대량 합성이 가능할 것으로 기대되고 있다. 본 연구에서는 전북대학교 고온플라즈마 응용연구센터의 60&200 kW의 고출력 ICP (RF) 열 플라즈마 시스템을 이용하여 LTO (Lithium Titanium Oxide)와 IZTO (Indium Zinc Tin Oxide), Barium Borosilicate Glass (K2O-BaO-B2O3-SiO2)의 다성분계 나노 복합체를 합성하였으며, FE-SEM, TEM, XRD, ICP-OES를 이용하여 그 특성을 분석하였다.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1998.05a
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• pp.11-15
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• 1998

증발냉각시스템의 원리는 물이 수증기로 상태변화할 때 필요한 기화열을 주변으로부터 공급받으면서 공기의 온도가 감소하는 것이다. 이것은 덥고 건조한 지역에서는 매우 효과적이지만 상대습도가 높은 지역에서는 냉방효과가 낮다. 따라서 국내의 모든지역에 증발냉각시스템의 적용이 적합한지는 의문이다. (중략)

• Tunnel and Underground Space
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• v.17 no.1 s.66
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• pp.56-65
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• 2007

A new underground LNG storage concept in the rock mass has been developed by combining underground cavern construction and new ice-ring harrier technologies with the conventional cryogenic insulation system. Technical feasibility of the storage system has been verified through construction and operation of the pilot storage cavern and a full-scale project is expected to start in the near future. One of the most important issues in the LNG storage system is the operational efficiency of the storage to minimize heat loss during a long period of operation due to the cryogenic heat transfer. This paper presents several important results of heat transfer and coupled hydro-thermal analyses by a finite element code Temp/W and Seep/W. A series of heat transfer analyses for full-scale caverns were performed to determine design parameters such as boil-off gas ratio (BOR), insulation thickness and pillar width. The result of the coupled hydro-mechanical analysis showed that BOR for underground storage system remains at about 0.04 %/day during the early stage of the operation. This value could be even much lower when the discontinuities in the rock masses are taken into consideration.

• 월간 기계설비
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• s.71
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• pp.50-58
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• 1996