• Journal of Bio-Environment Control
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• v.6 no.3
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• pp.183-189
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• 1997

This study was performed to Investigate size of droplet sprinkled from mini-sprinkler. Twelve different kinds of the sprinkler having various structures and sizes of nozzle orifices were selected and tested. Diameters of the droplet reached at several distances from a sprinkler were measured by a machine vision system and the volume median diameters (VMM) were determined statistically. The size of droplet was not affected much by the size of nozzle orifice of a sprinkler but was rather more affected by structure of the sprinkler, especially by the shape of spreader of the sprinkler. Experiment of varying pressure of sprinkling water validated that the size of droplet was inversely proportional to water pressure powered by 1/3. Hence the size of droplet at any water pressure could be easily estimated from experimental data. The size of droplet increased as travel distance of the droplet increases in a relationship of and order function. The size of droplet of the tested sprinkler were in the ranges of 100-300fm within 1m of droplet travel distance, 230~470${\mu}{\textrm}{m}$ within 1~2m of droplet travel distance and 300~770${\mu}{\textrm}{m}$ within 2~3m of droplet travel distance.

• Journal of Bio-Environment Control
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• v.5 no.2
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• pp.194-201
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• 1996

A series of experiments to analyse and to compare performance of various types of mini-sprinkler was carried out. Twelve kinds of the sprinkler, which have various sizes of nozzle orifice diameter and structures of spreader, were selected to be tested. Flow (water sprinkling) rate and sprinkling intensity pattern from a sprinkler were measured as a first part of this study, and the results are as follows. Sprinkler flow rate of various sizes of nozzle orifice and applied water pressures could be predicted by Torricelli's theorem. Discharge coefficients of the Torricelli's theorem for the sprinkler nozzle of various sizes were determined by the experiment as 0.90- 0.95, 0.80-0.82 and 0.76-0.79 for 0.8, 1.2 and 1.6 mm of nozzle orifice diameter, respectively. Experiments on sprinkling intensity pattern resulted that nozzle orifice diameter and applied water pressure are major variables for uniformity of the sprinkling intensity. More uniform sprinklering patterns were noted with smaller nozzle orifice diameter of a sprinkler and at lower sprinkling pressure. Besides the variables, structure of spreader of a sprinkler is also an important variable for the uniformity of sprinkling intensity.

• Fire Science and Engineering
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• v.22 no.2
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• pp.116-120
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• 2008

According to the Fire Services Act revised in 2005, it has been required to set up sprinkler systems to all floors to the newly builded apartments having above 11 floors. But, according to the Fire Services Act before 2005, it had been required to set up sprinkler systems from 16 floors to the top floors to the apartments having above 16 floors. This case is the accident that a victim was dead by the fire which is inferred as an accidental fire by a cigarette butt in a 17th floor apartment unit in an apartment having 17th floors and that the bereaved family called in question why the sprinklers non worked at the fire. Through the field investigation, we checked that the sprinklers worked well when the fire detectors at the 16th floor of the apartment were operated and that the sprinklers non worked when the fire detectors at the 17th floor of the apartment were operated. We made clear that the cause of the sprinkler non-working at the 17th floor is the programming error of the sprinkler controller.

• Journal of Bio-Environment Control
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• v.16 no.3
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• pp.210-216
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• 2007

A study was conducted to find mechanism and spray characteristics of a mini-sprinkler with downward spray to develop a new design type to be able to prevent drop water. The experiments were executed in a plastic greenhouse to minimize the effect of the wind. Data was collected at five different operation pressures and at 4 different raiser heights. Spray characteristics of the sprinkler such as effective radius, effective area, mean application depth, absolute maximum application depth, effective maximum application depth and coefficient of variation were determined. In order to analyze the mechanism and packing supporter of sprinkler, the numerical simulation using ABAQUS was performed. The optimum pressure for preventing drop water was determined.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2013.11a
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• pp.210-210
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• 2013

본 연구는 산림 내 시설물의 산림환경 특성 분석을 위하여 2013년 3월 9일부터 10일 이틀 동안 280ha의 산림 피해면적과 57동의 시설물 피해를 준 울주산불에 대하여 현장조사를 실시하였다. 조사 대상물은 주택 15개소, 비닐하우스 1개소, 축사3개소 등 총 19개소에 대하여 2013년 3월부터 5월까지 현지조사를 실시하였다. 조사항목은 시설물의 입지여건, 임상분포, 주변 산불인자, 시설물 외벽구조제, 산불 등 화재진화를 위한 소방시설 여부, 기타 산불 등 화재방지를 위한 시설, 보호시설과 산림과의 거리 등 총 7개 항목을 작성하여 피해시설물 및 미피해시설물의 특성을 분석한 결과 입지여건의 경우 피해시설물과 미피해시설물은 1~2개의 진 출입로를 갖고 있었고, 도로 폭은 7m 내외로 비슷한 여건이었다. 주변 임상은 침엽수, 임분 밀도는 중, 밀임분이었다. 비가연성 외벽구조제는 피해시설물 보다 미피해시설물에 많았고, 피해시설물과 미피해시설물의 시설물 주변 가연물질 관리상태는 모두 양호하였다. 반면, 급수시설 및 스프링클러, 방화선, 방화벽 등 소방시설 및 화재방지 시설은 미피해시설물이 피해시설물보다 더 많이 구축되어 있었고, 산림과의 이격거리는 피해시설물 평균 20m, 미피해시설물 평균 25m로 조사되었다.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.190-190
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• 2011

사회 다변화 및 급속한 경제성장과 도시밀집화로 인하여, 화재의 발생으로 인하여 막대한 인명피해 및 대규모의 재산상의 피해가 지속적으로 발생하고 있다. 이러한 화재의 피해를 예측하기 위해서는 실제 규모의 화재실험이 매우 유용하지만, 막대한 비용과 현실적 제약조건으로 인하여 실제 실험에는 많은 어려움이 따른다. 따라서 막대한 예산이 소요되는 실제규모의 화재실험의 대체방법으로 실제를 모사하는 축소모형 화재모의실험 및 컴퓨터를 이용한 화재 시뮬레이션 기법이 널리 이용되고 있다. 본 논문에서는 범용 컴퓨터를 이용한 화재 시뮬레이션 기법(CFAST)을 이용하여 수직 공간 구성을 가지는 단독주택의 화재 성상을 검토하였다. 시뮬레이션 모델로는 단독주택을 대상건물로 하여 2층으로 수직 공간을 가지는 단독주택 건물에 대한 모의 화재 시뮬레이션을 수행 하였다. 화재 시뮬레이션 결과는 각 구획실별 온도, 일산화탄소량, 공기 중 산소량 등을 도출하여 기존 이론에 의한 화재성장 그래프와 시뮬레이션 데이터를 비교하여 정확도를 검토하였다. 본 논문에서는 두가지의 시나리오를 작성하여 화재 시뮬레이션 프로그램의 결과 값을 분석하였다. (1) 시나리오 1 : 화재시뮬레이션 대상건물 1층 거실(2번방)에서 스프링클러 미 설치시 화재가 발생한 경우를 가정하여 수평방향인 3번방과 수직방향인 7번방의 화재 확산 피해정도를 살펴보고, 화재 그래프의 이론값과 실험값의 차이를 비교하여 그 정합성을 검토하였다. 발화물질은 Curtain, TV set, Sofa, Table으로 하며 시간은 60초 간격으로 총 3600초(1시간)를 분석 하였고, 발화지점의 온도, 일산화탄소, 공기중 산소 농도를 분석하였다. (2) 시나리오 2 : 시나리오 1과 동일한 화재발현 조건으로 스프링클러가 설치되어 있을 때 화재 발생 했을 경우, 수평방향인 3번방과 수직방향인 7번방의 화재 확산 피해를 시나리오 1과 비교 검토 하였다. 기존 이론에 의한 화재 성장 그래프와 이번 시뮬레이션 결과값을 토대로 만든 그래프 형태를 비교해보면 두 그래프의 형태가 비슷한 형태를 나타내어 Flash Over 현상과 Back Draft 현상이 이론값과 같은 경향을 나타내고 있음을 확인 할 수 있었다. 따라서, 본 논문에서 수행한 화재 시뮬레이션 기법으로 건축물의 실제 화재시의 피해정도를 예측하는 데 유용하게 활용될 것으로 판단된다.

• Fire Science and Engineering
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• v.24 no.4
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• pp.69-78
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• 2010

In this study, Fire Hazards were evaluated through computer simulation using FDS program for an apartment fire accident. The results of fire simulation showed that the maximum heat release rate in the case of no sprinklers activation was 7,700 kW which was about 16 times of that in the case of sprinklers activation, 497 kW and there was a very high fire hazard due to the backdraft phenomenon when the door of fire room was forced to open. Regarding the hazard time of fire room temperature and detection time of detectors, available evacuation time was 32.5 seconds of minimum to 53.5 seconds of maximum. In the case of sprinklers activation, fire hazard in the apartment was showed to be very low due to the fire control by the spray cooling of sprinklers. This study shows that what a important function for fire safety is the activations of fire sprinkler system and emergency alarm system and what a large loss can cause if these systems don’t activate in fire accidents.

• Fire Science and Engineering
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• v.32 no.4
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• pp.86-94
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• 2018

A sports center fire in Jecheon caused 29 deaths and 40 injuries. This study focused only on the structural factors of the building and equipment to investigate the causes of casualties based on the fire investigation results at the sports center. The structural factors of the building and equipment were a piloti-type parking lot, lack of a fire compartment between the piloti-type parking lot and lobby, lack of an installed sprinkler system, lack of an installed fire door in the main stairs on the $1^{st}$ floor, lack of an installed fire water tank on the rooftop, an installed pocket fire door in the main entrance on the $2^{nd}$ floor, poor fire compartments in an EPS space and a pipe pit and on each floor, a leak in the joint of a drain pipe, plywood installed in the hoistway of the freight elevator and interior wall, illegal remodeling of a closed rooftop structure, which cannot discharge smoke and heat, installed styrofoam insulation in the inside of the parking lot ceiling, an installed tempered glass window, which cannot be opened in the ladies bathroom on the $2^{nd}$ floor, and a finished dryvit exterior wall.

• Fire Science and Engineering
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• v.33 no.4
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• pp.130-139
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• 2019

The electronics factory fire, that occurred at 15:40 on August 21, 2018, killed nine people and injured six. This study analyzes the causes of many of the casualties from the fire, and is based on fire investigation results and so on. The findings suggest that major causes included failure of the automatic alarm system to function, failure of the emergency broadcasting system to function, the fire suddenly spreading due to polyurethane foam in a ceiling on the 4thfloor, a power outage immediately after the fire started, a sprinkler system that was not working, a delay in reporting the fire, and improper management of fire facilities by a fire safety management company.

• Fire Science and Engineering
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• v.32 no.5
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• pp.57-66
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• 2018

A sports center fire in Jecheon that caused 29 deaths and 40 injuries was analyzed based on initial response and management in order to investigate the causes of the casualties. The aspects of initial response included delay of reporting 119, not being guided to the exit for the body scrubber on the $2^{nd}$ floor for escape, opening the fire doors of the exits on the $1^{st}$ floor and $3^{rd}$ floor, not closing the fire door of the main stairs on the $3^{rd}$ floor, and not doing an emergency broadcast. The management aspects included closing the alarm valve of the sprinkler system on the $1^{st}$ floor, starting-stop of the fire pump controller, neglecting leakage of water and electricity between the false ceiling and ceiling in the parking lot, hiding the exit light in the ladies bathroom lounge on the $2^{nd}$ floor and piling up things in the exit, neglecting the button of an automatic door on the $2^{nd}$ floor, conventional fire safety management, insufficient inspection of fire equipment, and not working fire shutters and smoke exhaust windows.