• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.491-492
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• 2003

The large amount of smoke produced near Lake Baikal was transported to Northeast Asia with high AOT (Aerosol Optical Thickness) as seen in satellite images. Aerosol retrieval using a separation technique was applied to MODIS (Moderate Imaging Spectroradiometer) and SeaWiFS (Sea-viewing Wide Field-of-view Sensor) data observed during 14-22 May 2003. Large AOT, 2.0~5.0 was observed on 20 May 2003 over Korea due to the influence of the long range transport of smoke aerosol plume from the Russian fires, resulting in high PM10 concentration was observed at the surface.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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• pp.518-525
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• 1997

A series of measurements and visualization to investigate the interaction of water sprays with pool fires is presented. Fire source is a small-scale pool burner with methanol, ethanol and gasoline. Measurements of temperatures, $O_2$, $CO_2$, and CO concentrations along the plume centerline are carried out to observe pool fire structures without water sprays. Visualization by the Ar-ion laser sheet shows flow pattern of droplets of the sprays above the pool fires. It is observed that in the case of methanol and ethanol, water sprays continuously penetrate into the center of fuel surfaces. The gasoline pool fire allows intermittent penetration of water sprays because of pulsating characteristics of the gasoline flame. To evaluate the cooling effect of the fuel surface by the sprays, the temperature was measured at the fuel surface. As soon as the mists reach the fuel surface of methanol and ethanol, the temperatures of the fuel surface decrease rapidly below the boiling point, and then the fires are extinguished. Due to the application of mist upon the gasoline fire, though the fuel temperature decrease abruptly at the time of the injection, such a rapid decrease do not continue till the extinction point.

• 한국산업안전학회:학술대회논문집
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• 한국안전학회 1997년도 추계 학술논문발표회 논문집
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• pp.43-48
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• 1997

아트리움 공간에서 화재 발생시 연기 유동에 대하여 두 가지 형태의 화재 모델인 zone 모델과 field 모델을 이용하여 시뮬레이션 했다. 사용된 zone model은 NIST에서 개발된 CFAST(version 1.6) 모델이며 field 모델은 전산유체역학 이론을 바탕으로 자체 개발된 화재 모델이다. 본 연구는 정육면체 모양의 아트리움 공간에서 연기 유동과 온도 분포에 대하여 해석하고자 한다. 화재로 인해 야기된 유동에 대하여 속도장과 은도장을 예측하기 위한 계산 과정은 유한체적법 및 비엇갈림격자계를 이용하여 질량, 운동량, 에너지 및 성분 보존 방정식등에 대한 3차원 비정상상태 지배방정식을 사용했다. 수치해석 결과 zone 모델과 field 모델의 화재 모델에 의해 예측된 연기 층 평균 경계놀이와 상부 더운 연기 층의 평균 온도에 대하여 거의 유사한 결과를 얻었다.

• 한국화재소방학회논문지
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• 제11권4호
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• pp.15-23
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• 1997

A series of measurements and visualization to investigate the extingushiment of water sprays with pool fires is presented. Fire source is a small-scale pool burner with methanol, ethanol and gasoline. Measurements of temperature, O2, CO2, and CO concentrations along the plume centerline are carried out to observe pool structures without water sprays. Visualization by the Ar-ion laser sheet flow pattern of droplets of the sprays above the pool fires. It is observed than in the case of methanol and ethanol, water sprays continuously penetrate into the center of fuel surfaces. The gasoline pool fire allows intermittent penetration of water sprays because of pulsating characteristics of the gasoline flame. To evaluate the cooling effect of the fuel surface by the sprays, the temperature was measured at the fuel surface. As soon as the mists reach the fuel surface of methanol and ethanol, the temperatures of the fuel surface decrease rapidly below the boiling point, and then the fires are extinguished. Due to the application of mist upon the gasoline fire, though the fuel temperature decrease abruptly at the time of the injection, such a repid decrease do not continue till the extinction point.

• 대한기계학회논문집B
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• 제26권5호
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• pp.703-709
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• 2002

In order to investigate the smoke movement in three dimensional room fires, the center fire, wall fire and corner fire plume in different sized fires were studied experimentally by rectangular pool fire using methanol as a fuel. As the fire size became larger for the center fires placed at the center of the floor, the air flow rate entrained through the opening, average hot layer temperature, flame angle deflected backwards and mean flame height was observed to increase. On the other hand, as the fire size became smaller, the neutral plane height in the door and time reached steady-state was observed to decrease. The average hot layer temperature, mean flame height and doorway neutral plane height obtained from comer fire were higher than those produced by wall fires and center fires. The simple model for describing the effect of walls on the mean flame height was presented. It was shown that the model provides a good description of the present measurements, when used with the assumption by Hansell(1993), that the increase of the average flame height is equal to the ratio of the open to the total perimeters of the trays. Also the two models for predicting the effects of walls on the mean flame height were presented. These models overestimated the measured values of the mean flame height above fuel trays close to a wall and in a corner by approximately 19-26%, respectively.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2010년 춘계학술대회논문집
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• pp.10-13
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• 2010

The flow field in road tunnel is influenced by some facts such as piston effect of vehicle's move, operation of ventilation facilities, natural wind and buoyancy effect of fire plume. Among those, jet fan is one of main ventilation facilities especially in longitudinal ventilation system of tunnel. In this study to analyze tunnel flow induced by operation of jet fan, numerical simulation has been carried out. The velocity distributions and streamlines in tunnel are examined to consider the three-dimensional characteristics of tunnel flow caused by jet fan.

• 한국대기환경학회지
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• 제23권3호
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• pp.311-321
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• 2007

Nowadays, concerns have much more growing regarding indoor air quality (IAQ) on the public transportation including railway vehicles. Last year Korea Ministry of Environment (ME) set new guideline for public transportation. In this study several factors were analyzed which may affect comfortableness of railway passenger cabin, and we monitored IAQ parameters (PM10, CO, $CO_2$, VOCs, temperature and humidity) to investigate the present pollution in passenger cabin. In general, the railway air quality was satisfactory. The PM10 and $CO_2$ level on all passenger cabin were below the new guideline level 1 for PM10 $(200{\mu}g/m^3)\;and\;CO_2(2,000ppm)$. Clustering method was carried out to classify the air polluting pattern of the cabin. As a result, the pollutants could be classified to 4 clusters and the origin of pollution is soil, diesel exhaust gas, abrasion of rail and plume.

• 한국대기환경학회지
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• 제20권4호
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• pp.437-450
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• 2004

Extensive forest fire activities occurred across the border in Russia, particularly east of Lake Baikal between the Amur and Lena rivers in May 2003. These forest fires released large amounts of particulates and gases into the atmosphere, resulting in adverse effects on regional air quality and the global radiation budget. Smoke pollution from the Russian fires near Lake Baikal was transported to Korea through Mongolia and eastern China. On 20 May 2003, a number of large fires were burning in eastern Russian, producing a thick, widespread pall of smoke over much of Northeast Asia. In this study, separation technique was used for aerosol retrieval application with imagery from MODIS aboard TERRA satellites. MODIS true-color image shows the location of fires and the grayish color of the smoke plumes over Northeast Asia. Aerosol optical thckness (AOT) retrieved from the MODIS data were compared with fire hot spots, ground-based radiation data and TOMS -based aerosol index data. Large AOT, 2.0-5.0 was observed on 20 May 2003 over Korea due to the influence of the long range transport of smoke aerosol plume from the Russian fires, while surface observed fine mode of aerosol size distribution increased.

• 한국화재소방학회논문지
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• 제23권6호
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• pp.111-115
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• 2009

아세톤 LIF와 Rayleigh 산란법 등 두 가지 레이저 측정 기법을 이용하여 Re수가 1,000 미만의 부력제트 노즐근처에서의 공기 유입을 실험적으로 조사하였다. 아세톤 LIF 실험결과 전체적인 혼합기구는 경계면에서의 불안정성에 의한 거대와구조로 판단되고, Re 수가 커질수록 유입되는 시점이 상류로 이동하며 그 양 또한 증가되었다. 또한 Rayleigh 산란법 결과는 상류에서도 혼합이 제트의 내부까지 이루어지고, 노즐에서 분사방향으로 진행할수록 주위공기의 유입이 제트 내부로 진행되고 있음을 알 수 있다. 이 실험결과로서 기존 등온기체모델에서 제트의 주위공기 유입을 고려하여야 한다는 사실을 입증할 수 있다. 또한, 이상적 플룸식에서 복사열손실을 0.35로 고려하였을 경우에 기존의 연기량 및 온도 예측과 근사한 결과를 얻을 수 있으며, 주위공기 유입효과를 고려하여 보다 간단하면서 정확한 등온기체 모델링 방법을 얻을 수 있다.

• Environmental Engineering Research
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• 제22권2호
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• pp.216-223
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• 2017

For the prediction of the ventilation rate for removing the non-isothermal concentrated fume from the semi-enclosed space, the computational fluid dynamics (CFD) analysis was done. Securing the proper ventilation conditions in emergency state such as in fire is crucial factor for the protection of the resident in the space. In the analysis for the determining the proper ventilation rate, the experimental study had the limitation for simulating the versatile conditions of fume development. The theoretical and computational method had been chosen as the alternate tool for the experimental analysis. In this study, the CFD analysis was done on the defined model which already had been done the experimental analysis by the previous workers. By comparing the prediction on the plume heights and the ventilation rates by the CFD analysis at, and in the parametric model of $1m^3$ with those of the previous experimental works, the feasibility of the computational analysis was evaluated. For the required ventilation rate analyzed by the CFD analysis was over predicted in 7.1% difference with that of the experimental results depending on the different plume height. With the comparison with the analytical Zukoski model at, the CFD analysis on the ventilation was under predicted in 8.3%. By the verification of the feasibility of the CFD analysis, the extended analysis was done for getting the extra information such as the water vapor distribution and $CO^2$ distribution in the semi-enclosed spaces.