• 한국재난정보학회 논문집
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• 제15권3호
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• pp.402-408
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• 2019

연구목적 : 포소화설비에 사용되는 중발포 소화약제는 기류에 영향이 적어 방출거리를 유지 할 수 있을뿐만 아니라 소화약제도 효율적으로 사용 할 수 있기 때문에 중발포기를 이용하여 발포배율 및 소화성능을 실험으로 밝히고자 한다. 연구방법 : 본 연구를 위해 중발포 시험장치를 제작하여, 합성계면활성 제포를 대상으 로 유류화재(B급) 소화성능 및 발포배율 분석과 포소화약제 소모량을 측정하고 분석하였다. 연구결과: 중발포기로 발포배율을 측정한 결과 팽창율이 26.1배의 중발포 배율로 나타났으며, 유류화재 20단위 소화모형 실험결과 소화시간이 고발포 및 저발포 보다 빠르게 나타나, 수동식설비인 호스릴 또는 중발포기 적용이 가능할 것으로 본다. 결론: 본 연구를 통해 중발포 포소화약제 발포성능 및 소화성능이 우수하게 나타나는 점을 고려하여 중발포 소화약제를 활용한 호스릴 또는 중발포기의 기술기준 도입이 필요하다.

• 한국화재소방학회논문지
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• 제22권5호
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• pp.83-89
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• 2008

ISO 7203-2의 고팽창포 표준 발포기를 이용하여 포수용액을 5기압에서 6리터로 방사하면서 풍량, 스크린 매쉬, 포수용액의 농도 및 소금물의 농도 등 외적 요인에 의한 발포 특성을 살펴보았다. 연구결과 풍량이 증가할수록 발포배율이 증가하는 경향을 보였으며 표준발포용 스크린이 평직 철망에 비해 발포배율이 높았다. 포수용액의 농도 증가에 따라 발포 배율과 환원시간이 긴 안정성이 좋은 포를 발생하였으며 소금물의 농도가 증가하는 경우는 발포 배율과 환원시간 모두 감소하는 경향을 나타내었다.

• 한국안전학회지
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• 제25권4호
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• pp.25-29
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• 2010

Foam concentrate is used for fire-extinguishing purposes, occurring foam, mixed with air. In huge oil-fire or the efficiency of fire-extinguishing with small quantity of water, Foam concentrate is used widely. However, perfluorooc tanoicsulfonate and nonylpenol that are included in Foam concentrate could be exposure in danger while they were discharged. The purpose of the research is the development of environment-friendly high expansion foam that exclude the dangerous substances and improvement of danger of the existing foam concentrate. The developed foam is analyzed as the environment-friendly foam in indexes of the environment-toxicity, the biodegradation appraisal, and the dangerous substances-detecting. In addition, the performances of expansion rate, discharge rate, and fire-extinguishing are suitable in the domestic regulation, so it is useful for fire-extinguishing in real fire situation.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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• pp.574-579
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• 2005

• 한국표면공학회지
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• 제51권1호
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• pp.47-53
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• 2018

Sn-based lithium-ion batteries have low cost and high theoretical specific capacity. However, one of major problem is the capacity fading caused by volume expansion during lithiation/delithiation. In this study, 3-dimensional foam structure of Cu-Sn alloy is prepared by co-electrodeposition including large free space to accommodate the volume expansion of Sn. The Cu-Sn foam structure exhibits highly porous and numerous small grains. The result of EDX mapping and XPS spectrum analysis confirm that Cu-Sn foam consists of $SnO_2$ with a small quantity of CuO. The Cu-Sn foam structure electrode shows high reversible redox peaks in cyclic voltammograms. The galvanostatic cell cycling performances show that Cu-Sn foam electrode has high specific capacity of 687 mAh/g at a current rate of 50 mA/g. Through SEM observation after the charge/discharge processes, the morphology of Cu-Sn foam structure is mostly maintained despite large volume expansion during the repeated lithiation/delithiation reactions.

• 한국자동차공학회논문집
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• 제17권4호
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• pp.118-125
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• 2009

Bumper is designed to protect the automotive frame without damage at low velocity. Expanded polypropylene (EPP) foam is used in the bumper as an energy absorbing material. In order to exactly predict the energy absorbing performance of the foam material under impact loading condition, it is important to use high strain rate material properties. In this study, a new apparatus for dynamic compression tests was developed to investigate the high strain rate behavior of EPP foams. Three kinds of EPP foams which have different expansion ratios were tested to investigate the quasi-static and dynamic compression behavior. Quasi-static compressions were performed at low strain rates of 0.001/s, 0.1/s and 1/s. The dynamic compressions were carried out at high strain rates of 50/s and 100/s with the developed apparatus. It was observed that the EPP foam has significant strain rate effect as compared to quasi-static behavior.

• 한국기계가공학회지
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• 제18권11호
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• pp.63-68
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• 2019

The dimensional quality of flexible foams is often difficult to be evaluated through general machine vision inspection methods due to the free deformation of the outer shape. For the evaluation of the dimensions of flexible foams, methods of estimating the size of the product through the expansion rate of the product surface are evaluated. Specimens with various dimensions and surface gratings are prepared, and the degree of surface expansion is measured through machine vision. The correlation, between the measured surface grid size and the actual size of test specimens, is analyzed. We further analyze the correlation between the size of test specimens and the position of the surface grid. This study provides a basis for estimating the actual dimensions of specimens by measuring the surface expansion of flexible foams.

• Elastomers and Composites
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• 제35권2호
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• pp.106-114
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• 2000

상온에서의 충격 흡수특성과 compression set 특성을 향상시키기 위하여 ethylene vinyl acetate copolymer (EVA)와 styrene vinyl isoprene styrene triblock copolymer (SVIS)를 블렌드하여 발포체를 제조하였다. 발포제 및 EVA/SVIS 블렌드비가 발포배율 및 기계적 물성에 미치는 영향을 조사하였다. SVIS 함량이 증가함에 따라 블렌드의 점도는 증가하였고 가교 속도는 감소하였으며, 발포배율은 감소하여 비중은 증가하였다. 발포제 함량 증가, 즉 발포배율 증가에 따른 반발탄성은 변화가 없는 반면에, SVIS 함량 증가에 따라 발포체의 상온에서의 tan ${\delta}$ 값은 증가하였으며 따라서 반발 탄성은 감소함을 알 수 있었다. EVA/SVIS 블렌드 발포체에서 SVIS 함량 증가에 따라 가교밀도와 비중이 증가하므로 compression set 값도 낮은 값을 나타내었다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2001년도 추계학술대회 논문집
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• pp.289-292
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• 2001

Aluminium foams, having a closed cell structure, fabricated by applying the powder compact method and an induction heating were studied. The powdered A6061 mixed with the powdered titanium hydride as a foaming agent was hot pressed into a foamable precursor. The resulting precursor was foamed by induction heating up to desired temperature. The effects of the titanium hydride content ($0.3{\~}1.5 wt.\%$), pressing pressure of the foamable precursor material (50-150kN), the forming temperature ($610{\~}690^{\circ}C$) and heating rate during foaming on the expansion behavior of the foam were investigated.

• Journal of Advanced Marine Engineering and Technology
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• 제22권6호
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• pp.871-879
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• 1998

The refrigerator consists of many components such as compressor condenser expansion valve evaporator and the cabinet which filled by urethane foam. In this paper the heat leakage of refriger-ator is measured by the new experiment method which is different from a present method, The devi-ation of the UA(overall heat transfer coefficient times area) between the simulation and experiments is about 7-8%. Using the modeling of various components of refrigeration system a performance analysos of CFC 12 and HFC 134a is performed numerically on the UA. As the results of this study according to increase the heat leakage the refrigeration load and mass flow rate of refrigerant are increased. And the increase of the mass flow rate results in the increase of the condensing and evapo-rating temperature. Therefore according to increase of the heat leakage the COP leads to increase because the increase of refrigeration capacity is larger than the increase if compressor power.