• 해양환경안전학회지
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• 제28권5호
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• pp.753-763
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• 2022

우리나라의 수산 양식의 대부분이 이루어지는 연안과 내만에 최근 빈번한 고수온 현상으로 매년 막대한 양식 피해가 발생하고 있다. 2018년~2021년의 최근 4년간의 7월은 이례적인 고수온, 장마, 태풍 등에 의해 1990년 이후 수온의 연별 변동성이 1994년~1997년에 이어 두 번째로 크게 나타났다. 동·서·남해의 대표적인 고수온 양식피해 우심해역(천수만, 가막만, 구룡포)에 대한 열속과 열수지 분석을 통해 여름철 천수만과 가막만의 고수온 발생은 주로 대기로부터 해수면을 통한 열유입에 의한 것임을 확인하였다. 벌크식으로 계산한 순열속과 수온변화로부터 계산한 해양 열 저장률로부터 4년간(2018년~2021년)의 7월 평균 해양 열 수송률을 추산한 결과, 서산 창리는 순열속의 13.5 %, 여수 신월은 순열속의 62.3 %가 외부로 유출되는 것으로 계산되었다, 구룡포 하정은 순열속의 22.2 %가 평균적으로 외부로 유출되는 것으로 평가되었으나, 냉수대 발생 유무에 따라 연도별로 해양 열 수송률이 순열속의 -174.5 %에서 132.5 %까지 큰 차이를 보였다.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 후기학술대회논문집
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• pp.256-257
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• 2005

This paper has been carried out to investigate heat transfer characteristics of loop type capillary heat pipe using R141b as a working fluid. In an experiment heat load are changed from 50W to 250W and the temperature of cooling water is fixed to 20$^{circ}C$ . The heat pipe is composed of 10 turns and outer diameter of heat pipe is 3.2mm. The results show that heat transport rate of this type heat pipe using R141b as a working fluid is good.

• 한국의류학회지
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• 제19권1호
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• pp.36-50
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• 1995

The purpose of this study was 1) to estimate the improvement of thermal storage/release and moisture transport properties of PEG-treated acrylic athletic socks and suggest the optimum add-on for PEG treatment, 2) to investigate wear performance of untreated cocks and two kinds of socks treated with PEG of minimum and optimum add-on respectively, and 3) to consider the effect of thermal storage/release and moisture transport properties of PEG- treated socks on the wear performance and the subjective comfort zone. Thermal activities of specimens treated by PDC were evaluated on a DSC by measuring the heat of fusion on heating and the heat of crystallization on cooling. Moisture regain, absorption speed, wickability, water retenti on value, and water-vapor permeability were measured. In the wear trials that the subjects performed a subsequent exercise protocol wearing three differently treated socks in a conditioned environment ($14\pm2^{\circ}C$, 65$\pm$2% R.H.), microclimate temperature and humidity, and subjective wear sensations including thermal sensation, wettedness, softness, fit, and overall comfort were obtained. PEC-treated specimens with more than 20% add-on showed thermal storage on heating and thermal release on cooling by a DSC and the heat contents of treated ones were generally proportional to the add-ons. Moisture transport properties were highly improved after PEG treatment and increased rapidly with increasing add-on. The tendencies were, however, relaxed above 50% add-on and the treated knits were much stiffer above that add-on. In the wear trials of untreated, PEG add-on 20%, and 50% acrylic socks, the changes of microclimate temperature of 50% socks were significantly less than that of 20% socks. PEG add-on 50% socks showed significantly less changes of microclimate humidity than other two kinds of socks. Three kinds of socks showed significant differences in overall comfort and add-on 50% socks were accepted more comfortable than other two kinds of socks. Comfort zone of foot was extended after PEG treatment on socks and it implied that the subjects wearing PEG- treated socks felt comfortable in wider ranges of microclimate temperature and humidity.

• 한국기계연구소 소보
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• 통권9호
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• pp.21-28
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• 1982

• 천문학회보
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• 제28권2호
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• pp.43-43
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• 2003

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 하계 학술대회 논문집
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• pp.142-147
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• 2000

• 한국결정성장학회지
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• 제14권4호
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• pp.155-159
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• 2004

열교환법을 활용한 사파이어 단결정 성장 공정에서 도가니 형상 변화가 결정 온도와 고/액 계면 형태에 미치는 영향에 관해 고찰하기 위해 유한요소법, implicit Euler법, frontal 해석 연산을 활용한 수치해석을 수행하였다. 개발된 컴퓨터 시뮬레이션 기법은 고/액 계면의 형상이 반구 형상에서 평면 형상으로 전환되는 열전달 현상 해석에 효율적이다. 본 연구에서는 고/액 계면의 휨도를 개선하기 위해, 도가니 밑면의 다양한 형상을 고려하였으며, 도가니 형상은 공정 최적화 변수로 고려되어야 한다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.1052-1057
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• 2004

A small-scale loop heat pipe with polypropylene wick was fabricated and tested for its thermal performance. The container and tubing of the system was made of stainless steel and several working fluids were used to see the difference in performance including methanol, ethanol, acetone, R134a, and water. The heating area was 35 mm ${\times}$ 35 mm and there were nine axial grooves in the evaporator to provide a vapor passage. The pore size of the polypropylene wick inside the evaporator was varied from 0.5 m to 25 m. The size of condenser was 40 mm (W) ${\times}$ 50 mm (L) in which ten coolant paths were provided. The inner diameter of liquid and vapor transport lines were 2.0 mm and 4.0 mm, respectively and the length of which were 0.5 m. The PP wick LHP was operated with methanol, acetone, and ethanol normally. R134a was not compatible with PP wick and water was unsuitable within operating limit of $100^{\circ}C$. The minimum thermal load of 10 W (0.8 W/cm2) and maximum thermal load of 80 W (6.5 W/cm2) were achieved using methanol as working fluid with the condenser temperature of $20^{\circ}C$ with horizontal position.

• Journal of Mechanical Science and Technology
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• 제19권4호
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• pp.1052-1061
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• 2005

A small-scale loop heat pipe (LHP) with polypropylene wick was fabricated and tested for investigation of its thermal performance. The container and tubing of the system were made of stainless steel and several working fluids were tested including methanol, ethanol, and acetone. The heating area was $35\;mm\;{\times}\;35\;mm$ and nine axial grooves were provided in the evaporator to provide vapor passages. The pore size of the polypropylene wick inside the evaporator was varied from $0.5\; {\mu}m\;to\;25\;{\mu}m.$ The inner diameter of liquid and vapor transport lines were 2.0 mm and 4.0 mm, respectively and the length of which were 0.5 m. The size of condenser was $40\;mm\;(W)\;{\times}\;50\;mm\;(L)$ in which ten coolant paths were provided. Start-up characteristics as well as steady-state performance was analyzed and discussed. The minimum thermal load of $10\;W\;(0.8\;W\;/cm^{2})$ and maximum thermal load of $80\;W\;(6.5\;W\;/cm^{2})$ were achieved using methanol as working fluid with the condenser temperature of $20^{\circ}C$ with horizontal position.

• 대한조선학회논문집
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• 제49권6호
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• pp.541-549
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• 2012

The study adopted a freezing prevention method of the upper deck which used heating coil, and carried out numerical analysis by using ANSYS 13.0 CFD for design guide of the vessel operating in cold region. It is based on the experimental results of the anti-icing performance tests which were carried at cold room chamber in MOERI. Numerical analysis for the design guide was performed by considering S.S.T. (Shear Stress Transport) turbulent model for flow separation effects and the turbulence which occurred in interfaces of the numerical model in order to express appropriate heat transmission phenomenon. The numerical result shows average temperature of the upper deck surface appeared similarly compared with the indoor chamber test. The design guide for optimum freezing prevention presented through heat transmission capability and interval of the heat coil in various outdoor temperature($10^{\circ}C{\sim}-30^{\circ}C$) and wind speed(1m/s~7m/s).