• Fire Science and Engineering
• /
• v.27 no.1
• /
• pp.31-38
• /
• 2013

The pressurized smoke control system is important for fire safety in building because it is directly concerned with egress time of people. Even though the damper plays an essential role in the pressurized smoke control system, the phenomena of backflow smoke occurs for a certain the damper position. The research for a position of damper effects on distribution of air flow at the fire door is not performed. In this study, numerical simulation using FDS 5.5 was carried out to analyze the effect of the position of damper on flow distribution at the fire door. To simulate real situation, effects of opening and closing of fire door was considered. As a result, when HRR was between 200 kW and 400 kW, in the case which the damper was on the opposite wall of the fire door, the back flow to the vestibules was large compared to the two other cases of damper position. But when HRR was above 400 kW, Effect on damper position was not occurred.

• 한국방재학회:학술대회논문집
• /
• 2011.02a
• /
• pp.84-84
• /
• 2011

터널화재의 위험요소에 대한 해석을 위해서는 실제 상황을 재현한 실대형 실험이 가장 유용하겠지만 현실적으로 시간적, 공간적, 경제적인 제약이 따르기 때문에 CFD Modeling 기술의 이용 및 검증이 필요하고, 실제 상황에 가까운 현상의 재현을 위해서는 시뮬레이션의 정확도에 대한 향상이 필수적이다. 또한, CFD Modeling을 터널화재에 적용할 때 시뮬레이션의 질에 영향을 미칠 수 있는 요소들에 대한 결정이 선행되어야 한다. 우선, 터널의 기하학적 구조와 경계조건의 확립이 필요한데 필요한 정보를 얻기 위해서 어느정도 길이의 터널이 적절한지에 대해 생각할 필요가 있으며, 단면변화에 대한 결정을 통해 모델링을 수행하여야 한다. 모델링 작업이 선행된 후에 화재의 위치, 성장률, 최대 크기, 환기시스템 사항 등의 고려가 필요한데 이러한 조건들은 CFD Modeling의 결과에 직접적인 영향을 주기 때문에 충분한 사전조사가 이루어져야 하고, 각 사항들의 변수를 고려하여 다양한 화재시나리오의 도출이 가능할 수 있다. 마지막으로, 화재에서 발생된 열중 약 30%가 복사에 의해 주위 벽으로 전달될 수 있고 열은 연기가 가득찬 영역내에서 재분배될 수 있는데, 열전달 및 연기의 유동 등에 관한 자료를 기초로 화재현상에 대한 분석이 가능하다. 이러한 과정들을 통해 실제 상황에 가까운 설계화재 시나리오를 예측할 수 있다. 본 연구에서는 우리나라 최장대터널인 죽령터널에 대해 합리적인 가정을 통한 설계화재 시나리오를 기초로 화재시뮬레이션은 FDS(Fire Dynamics Simulator) 프로그램을 사용하여 화재 및 연기의 이동 양상을 분석하고, 피난시뮬레이션은 SIMULEX 프로그램을 사용하여 피난시간을 예측 함으로써 터널화재의 CFD Modeling에 의한 피난안전성을 검토하고자 한다.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 2011.04a
• /
• pp.361-366
• /
• 2011

본 연구에서는 무인운영이 예정되어 있는 경량철도 지하역사 화재 시 안전대책을 강구하기 위하여 다양한 시나리오의 화재상황을 모사하여 FDS 사용코드를 이용해 화재유동현상을 분석하였다. 해석경계조건은 전동차 내부공간을 포함한 지하 3개 층과 설계에 반영된 환기설비를 적용하였으며, 약 500만 개의 격자를 34개 블록으로 나누어 계산하였다. 비상탈출 동선을 파악하여 주요 위치에서 피난경로상의 각 층 바닥으로 부터 1 m 높이의 한계온도와 연기층의 도달시간을 시나리오 별로 분석하여 보았다.

• Journal of the Korean Society of Hazard Mitigation
• /
• v.8 no.5
• /
• pp.23-33
• /
• 2008

Extra dosed bridge among the Cabled-stayed bridges have been increasingly built in korea in recently. But such bridges were often damaged by fire due to car collison. In this study Extra dosed bridges among the cabled-supported bridges are selected to analysis model frequently to be designed and/or constructed in recent and furture in this study. COSMOS FloWorks 2007 software are used for Heat Transfer Analysis and Thermal Stress Analysis. The safety of wire, HDPE pipe and stainless steel pipe are investigated. In the case of the constant of the temperature of the heat source, the significant three variables for the analysis are selected for study : (1) the distance between the fire-proof bulk head and the heat source, (2) wind velocity, (3) the height of the end of Stainless steel pipe.

• Fire Science and Engineering
• /
• v.34 no.4
• /
• pp.36-44
• /
• 2020

It is necessary to predict the activation time of fire detectors accurately to improve the reliability for evaluating the required safe egress time (RSET) in performance-based fire safety design. In this study, problems of the plunge test, which is widely applied in assessing fire detectors, were examined through experiments and numerical simulations. In addition, a new shield-cup test method was proposed to address these problems. A fire detector evaluator (FDE) developed in a previous study was applied to ensure measurement accuracy and reproducibility. During the plunge tests, a significant measurement error was observed in the activation time of the smoke detector because of the rapid flow change when the detector was input. However, during the shield-cup tests, slight changes occurred in the flow inside the FDE when the detector as exposed to smoke. In conclusion, the proposed shield-cup test method is expected to be useful for evaluating the response characteristics of fire detectors more accurately in simulated fire environments.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 2011.11a
• /
• pp.490-493
• /
• 2011

공연과 스포츠 문화의 발전으로 한정된 구역에 불특정 다수의 사람들이 모이는 일이 빈번하게 일어나고 있다. 이에 비례하여 불특정 다수의 압사사고 역시 자주 일어나고 있다. 이러한 압사사고는 인도, 일본, 독일 등 세계 곳곳에서 일어나며, 국내에서도 자주 발생하는 압사사고는 단순히 안전불감증 문제로만 치부되어 특별한 과학적 해석이 행해지지 않는 문제점을 가지고 있다. 이러한 압사사고는 보행자의 심리와 물리적 충돌에 의한 힘에 의하여 일어나는 특징을 가지고 있다. 따라서 본 연구에서는 집합행동심리를 고려한 이산요소법을 활용하여 과밀상태하의 병목구간에서의 보행자 피난 유동 해석 연구를 진행한다. 연구의 변수로는 출구의 폭, 출구 각도 그리고 보행자의 혼란정도를 나타내는 Panic Factor가 선택되었다.

• Fire Science and Engineering
• /
• v.21 no.1 s.65
• /
• pp.1-6
• /
• 2007

This paper investigated the fire and smoke behavior in the compounded multiplex theater using FDS with various spacial and boundary conditions to ensure the fire safety of the multiplex. The results showed that more rapid temperature increase and smoke can be induced near the exit door for the lower fire load duo to the horizontal smoke movement. The overuse of fire resistants can generate more smoke while delaying combustion rate, which can give adverse effect to the evacuation. The mal-function of the exhaust fan would obstruct smoke exhaust but also retard the function of sprinkler head.

• Proceedings of the SAREK Conference
• /
• 2005.06a
• /
• pp.159-159
• /
• 2005

• Journal of the Korean Society of Hazard Mitigation
• /
• v.1 no.1 s.1
• /
• pp.157-163
• /
• 2001

The objective of the present study is to predict the characteristics of the fire and smoke propagations in a clean room. Numerical calculations have been performed by using the finite volume method to obtain temperature and velocity distributions in the clean room. In odor to account for the turbulent flow characteristics, the standard $k-{\varepsilon}$ model is used. From this study, it was found that the fire propagation could be fully developed only after 150 seconds when the ventilation system in the clean room was off. And the smoke mass fraction showed a similar distribution as the gas temperature. Since the simulated fire was proceeded up to $20{\sim}30%$ of the room within 60 seconds. it could be recommended that the occupants should be evacuated from the room within 30 seconds.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.22 no.10
• /
• pp.665-671
• /
• 2010

In the present study a 1D-3D numerical simulation was performed to analyze the fire safety in a rescue station of a long railroad tunnel equipped with a mechanical ventilation. The behavior of hot air was studied for the emergency operation mode of ventilation system in case of fire in the rescue station. The 1D simulation was carried out for entire tunnel region. Detailed 3D CFD simulation was performed for the rescue station area in the central region of the tunnel by using the result of the 1D simulation as the boundary condition of the 3D simulation. Various type of cross passage installation were evaluated for the prevention of smoke diffusion to suggest the optimized interval of the cross passages in the rescue tunnel.