• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 한국화재소방학회 2011년도 춘계학술논문발표회 논문집
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• pp.214-218
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• 2011

대형 여객선(크루즈선)의 절반 이상을 차지하는 거주시설(accommodation), 즉 선실은 24시간 사람이 상주하는 구역임으로 화재로부터 안전하게 보호되어야 한다. 특히 선실의 발코니에서 화재발생 시 이를 통해 인근의 객실로 화재가 급격히 확대되므로 국제해사기구 (IMO)에서는 기준에 적합한 미분무수 소화설비를 설치할 것을 강제화하고 있다. 이러한 미분무 노즐은 IMO MSC/Circ. 1268에 따라 소화성능시험을 통해 형식승인을 득해야 하는데 본 연구에서 이러한 기준에 만족하는 미분무 노즐을 개발하고자 선실 발코니에 대한 화재시험을 수행하여 두 가지 노즐 형태에 대한 소화성능을 평가하였다.

• Fire Science and Engineering
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• 제21권2호
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• pp.111-117
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• 2007

Full scale fire suppression test by water mist system were performed in machinery engine room ($20m{\times}15m{\times}10m$) according to IMO MSC/circ. 1165. The K-factor and operating pressure were 2.4 and 80 bar respectively. To assess the prediction capability of numerical simulation, FDS simulation was performed at the same operating condition with the full scale experiment. It was found that FDS simulation had the limitation for the fire extinguishing time prediction but was able to predict the spatial temperature distribution.

• Fire Science and Engineering
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• 제23권3호
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• pp.61-66
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• 2009

We carried out the water mist fire extinguishing experiments with the 3 kinds of foaming agents varied on the nozzle height. Test result showed that 2% AFFF (Aqueous Film Forming Foam) and 1% synthetic foaming agent for water mist system are the faster extinguishing time than the pure water mist and 3% AFFF solution. Additionally, the best fire extinguishing performance of pure water mist was shown at 3.5m nozzle height and that of the foaming agents shown at 4m nozzle height.

• Proceedings of the KSME Conference
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.2983-2988
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• 2007

In the present study, the numerical investigation on the effects of water-mist characteristics has been carried out for the fire suppression mechanism. The FDS are used to simulate the interaction of fire plume and water mists, and program describes the fire-driven flows using LES turbulence model, the mixture fraction combustion model, the finite volume method of radiation transport for a non-scattering gray gas, and conjugate heat transfer between wall and gas flow. The numerical model is consisted of a rectangular enclosure of $L{\times}W{\times}H=1.5{\times}1.5{\times}2.0m$ and a water mist nozzle that be installed 1.8m from fire pool. In the study, the parameters of nozzle for simulation are the droplet size and the spray velocity. Finally, the droplet size influences to fire flume on fire suppression than spray velocity because of the effect of terminal velocity, and the optimal condition for fire suppression is that the droplet size and the spray velocity are $100{\mu}m$ and 20m/s, respectively.

• Journal of Power System Engineering
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• 제13권5호
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• pp.25-33
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• 2009

In the present study, the numerical investigation has been carried out to see the effects of water mist sprays on the fire suppression mechanism. The special-purposed program named as FDS was used to simulate the interaction of fire plume and water mists. This program solves the fire-driven flows using LES turbulence model, the mixture fraction combustion model, the finite volume method of radiation transport for a non-scattering gray gas, and conjugate heat transfer between wall and gas flow. The computational domain was composed of a rectangular space dimensioned as $L{\times}W{\times}H=4.0{\times}4.0{\times}2.5\;m^3$ with a mist-injecting nozzle installed 1.0 m high from the fire pool. In this paper, two types of nozzles were chosen to compare the performance of the fire suppression. Numerical results showed that the nozzle, type A, with more orifices having smaller diameters had poorer performance than the other one, type B because the flow injected through side holes deteriorated the primary flow. The fire-extinguishing time of type A was 2.6 times bigger than that of type B.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 한국화재소방학회 2010년도 추계학술발표회 자료집
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• pp.163-166
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• 2010

여객선 선실 등 선박 거주구역에 사용되는 노즐의 열응답 특성에 관한 실험적 연구를 수행하였다. IMO(국제해사기구)의 수계소화설비 성능평가 기준에 따르면 구주구역에 설치되는 소화시스템의 노즐은 조기 반응 응답 특성을 확보하여야 한다. 본 연구에서는 glass bulb의 선정과 풍동실험을 통해 반응 응답 값을 측정하였으며, 노즐 헤드 형상의 개선을 통해 IMO 기준이 요구하는 RTI(반응시간지수) < $50ms^{1/2}$의 조건을 만족하는 노즐 헤드를 개발하였다.

• Journal of Advanced Marine Engineering and Technology
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• 제37권8호
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• pp.946-952
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• 2013

Large scale fire tests were conducted to develop water mist nozzles as a component of fixed water- based fire fighting systems for Ro-Ro spaces and special category spaces. Fire scenarios for this system consist of two cases which are for cargo fire in a simulated truck and for passenger vehicle fire, and each case has 3 different tests according to the position between fixed water mist nozzles and fire source. Every experiment proceeded for 30 minutes and acceptance criteria were based on gas temperature, fuel package's damage and ignition of targets. This study primarily dealt with the experimental results of cargo fire and focused on fire suppression capability in accordance with discharge pressure, flow rate and flow characteristics like swirl and penetration of the developed water mist nozzles. It appeared that low pressure water mist nozzles with about 40 L/min were able to control fire occurred in Ro-Ro spaces.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 한국화재소방학회 2008년도 춘계학술논문발표회 논문집
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• pp.139-143
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• 2008

• Journal of ILASS-Korea
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• 제11권4호
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• pp.199-204
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• 2006

Numerical investigation has been performed to simulate the spray characteristics in mist-spray fire suppression nozzles in sense of design parameters. Two key shape factors in nozzle orifices. i.e. diameter and length are chosen as simulation parameters. Commercial softwares, FLUENT and FDS with the proper modelings were applied as numerical tools. Main performances of nozzles, i.e., K-factors, spray angles, droplet size, jet velocities and fire suppression time are analyzed for each parameter to find optimal design conditions.

• Journal of computational fluids engineering
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• 제11권4호
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• pp.56-61
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• 2006

Numerical simulation has been performed to investigate the characteristics of the mist flow through the fire suppression nozzles. The commercial CFD software, FLUENT with the proper modeling was applied for analyzing both the internal and external flow of the spray nozzles. Computations were made for the full cone nozzle in the operation range of the low pressure and high flow-rate. To validate the present computational procedure, numerical results are compared with measurements in terms of K-factor, SMD, axial spray velocity and spray angles. Numerical results suggested that the present numerical model can be used as an adequate tool for a design purpose of mist-spray nozzles.