• Journal of the Society of Naval Architects of Korea
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• v.37 no.3
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• pp.110-121
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• 2000

Gas heating, high frequency induction heating and laser heating can be used as the heat-source of line heating. Most of shipyards have been using the gas heating method for line heating. It is difficult to control the residual deformation of gas heating. High frequency induction heating is more feasible for the automation of line heating rather than the gas heating method since it is easy to control the magnitude of heat input. In this study, a numerical model of high frequency induction heating process is proposed for the application of the line heating. The simulation process of the induction heating is composed of the electromagnetic analysis, the heat transfer analysis, and the thermal deformation analysis.

• Solar Energy
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• v.12 no.1
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• pp.95-102
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• 1992

A small scale solar collector system composed of a Fresnel lens of $0.5m^2$ area as a solar concentrator and a compact fluidized-bed solar receiver was developed. Performance and temperature distribution in the fluidized bed receiver were measured using SiC for particles and air for working fluid. The maximum gas temperature was attained up to 1250K at this moment. In this study, energy efficiency achieved by the present experiment was high for the small scale solar collector system and compact receiver.

• Radiation Oncology Journal
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• v.9 no.2
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• pp.171-176
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• 1991

To evaluate the temperature distribution according to the size of the electorde and the thickness of the phantom using 8MHz radiofrequency capacitive heating device, various sized electrodes and phantoms were used in combination. The radii of the electrodes are 10, 15, 20, 25, and 30 cm and the thickness of cylindrical phantoms with diameter 30 cm were 10, 15, 20, 25, 30, and 35 cm. When the thickness of the phantom was 25 cm or 30 cm, homogenous heating was achieved by using the electrode which diameter was equal to or greater than the thickness of the phantom. When the thickness of the phantom was 20 cm or less. homogenous heating was not achieved by using the electrode which diameter was equal to the thickness of the phantom, but achieved by the larger diameter of the electorode. When the sizes of paired electrodes were not equal, the smaller electrode side was preferentially heated.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.81.2-81.2
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• 2010

고체 산화물 연료전지(SOFC) 시스템은 스택과 기계적 주변 장치인 MBOP(Mechanical Balance of Plant), 그리고 전기적 주변장치인 EBOP(Electrical Balance of Plant)로 구성되어있다. SOFC는 일반적으로 $700^{\circ}C$ 이상의 고온에서 작동되기 때문에 효율적인 열 이용 및 열 관리가 중요하다. SOFC 시스템의 MBOP에는 상온의 연료가스들을 고온으로 가열하여 스택에 유입 시기키 위한 열교환기 및 촉매연소기 등의 장치들이 필요하며, 효율적인 열관리를 위해서는 고온에서 작동하는 장치들을 한곳에 통합하여 구성하는 것이 필수적이다. 본 연구에서는 SOFC 시스템의 MBOP(Mechanical Balance of Pant) 중 고온부에 해당하는 촉매연소기, 열교환기 및 스택이 통합된 스택 모듈을 제작에 앞서 개념 검증을 위해 열교환기 및 촉매연소기로 이루어진 프로토타입(prototype)의 SOFC 모듈평가 장치를 제작하였다. 열교환기는 Plate형으로 총 6개로 구성되어 있으며, 연료극과 공기극 가스라인에 각각 3개씩 배치하여 스택에 유입되는 연료 및 공기가 촉매연소기에서 나오는 고온의 배가스와 열교환되어 가열되도록 구성하였다. 촉매연소기는 honeycomb 타입의 촉매를 사용하였고, 촉매연소기로 유입되는 연료극 배가스와 공기의 균일혼합과 hot spot을 방지하기 위한 장치를 삽입하여 제작하였다. 제작된 SOFC 모듈평가장치는 시운전을 통해 각 장치의 성능 확인 후 반응면적이 $20{\times}20cm^2$ 인 단전지를 적층하여 연계 운전을 수행하였다.

• Journal of the Korean Chemical Society
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• v.45 no.5
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• pp.481-490
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• 2001

The purpose of this study was to find out the problems on the fractional distillation experiments in the middle school science textbooks based on the 6th curriculum and to suggest an efficient experiment method for the middle school students. The first step was the classification of the experiments in 8 science textbooks according to heating apparatus and liquid mixtures. The second step was doing each experiment 3 times followed by the experimental process in the textbooks. The third step was developing the alternative experiments for solving the problems found in the second step. The heating method used in the alternative experiments were direct heating, oil bath, and heating mantle. The results of the second step showed that the direct heating experiment of branched round flask was more close to the theoretical prediction than the experiment of water bath heating of branched test tube. Also the direct heating experiment of thermally insulated branched round flask was better than the result of the experiment which was not insulated. The results of the third step showed that the experiment using heating mantle regulated heating power by observing the temperature of distillate gave the closest result to the theoretical prediction. From the above results, it is concluded that the experiment using branched test-tube with water bath heating is not adequate for the fractional distillation and an alternative experiment using insulated branched round flask with heating mantle regulated heating power during experiment is recommended.

• Journal of the Korean Vacuum Society
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• v.2 no.3
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• pp.288-293
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• 1993

통전가열, 접촉냉각, 전기적 bias 및 시료 교환을 자유로이 할 수 있는 다기능의 새롭고 간단한 시료 고정장치를 저온 및 초고진공 상태에서 기체와 여러 방향의 시료표면 사이의 상호작용을 연구하기 위하여 고안하였다. 이 장치로써 2분 이내에 기판의 온도를 1600K에서 20K로 2분 이내에 냉각시킬 수 있었다. 그러므로 청결한 표면위에 수소나 He이나 Ne을 제외하고는 대부분의 기체를 흡착시킬 수 있게 되었다. 이러한 장치는 표면에서의 상변화, 기체와 표면의 화학반응의 연구에 중요하게 활용될 수 있다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.4 no.4
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• pp.356-362
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• 1994

We developed a computer controlled Czochralski puller which automated entire crystal growing processes. Crystal weighing technique was employed for an automatic diameter control. The performance of the system was evaluated by the growth of $LiNbO_3$ single crystals.

• Nuclear industry
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• v.17 no.5 s.171
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• pp.61-66
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• 1997

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.1
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• pp.33-39
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• 2015

This paper describes test result of the Supersonic Wing Structure and the utility of thermal test equipment, which is possible to heat rapidly and continuously above $1,000^{\circ}C$, the durability and reliability of which are improved compared with the existing equipment. Through the test, we could predict the amount of strength reduction of the wing due to aerodynamic heating, caused by exposure of high temperature. Recently the aerodynamic heating temperature of the supersonic flying object is rapidly increased. It is possible to carry out the High Temperature Strength Test on the hypersonic speed flying object with the newly designed thermal test equipment. Because of that, we can upgrade the High Temperature Strength Structure Test technique and test reliability.

• Korean Journal of Food Science and Technology
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• v.11 no.4
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• pp.258-263
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• 1979

A cylindrical focusing solar food dryer made with aluminum-laminated acryl film was demonstrated for the dehydration of agricultural product and its perfomance was analyzed with respect to the solar energy utilization and its scale-up technology. With one square meter reflector and a 74 cm copper pipe absorber, the heat exchange efficiency between air stream and absorber was 1.39 %. The installation of circular segment-baffle increased 33 % of the efficiency. In dehydration of radish-cut with this drier, 58 % of fuel consumption was saved. The relationship between reflector area and heat energy utilization was established for the scale-up purpose.