• Journal of the Society of Disaster Information
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• v.17 no.1
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• pp.1-9
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• 2021

Purpose: The purpose of this study is to analyze the differential pressure and velocity to prevent smoke backflow of Stairways Apartment House fire, and verified the effectiveness of smoke velocity standards proposed by NFSC 501A. Method: The smoke control design of the stairways apartment house of the real model and the performance of the velocity to prevent smoke backflow according to the window opening conditions of the living room were analyzed using the CONTAM program. Result: Although the differential pressure performance of the apartment's smoke control system was satisfactory, it was found that Performance of velocity to prevent smoke backflow did not come out according to the opening condition of the living room window. Conclusion: In the case of Stairways Apartment House, it is necessary to review the method of making exceptions to the 'velocity to prevent smoke backflow' standard required by the National Fire Safety Codes(NFSC 501A)

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.7
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• pp.335-342
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• 2014

The big issue in fire and life safety protection in atriums is that hot smoke can spread vertically via the atrium openings, and impact atrium floors remote from the fire. Three different strategies to provide fire and life safety protection for atrium space were evaluated in this study, using the FDS model. Strategy A is the atrium protection approach addressed in the Korean Building Fire Protection Code, where atria are required to be enclosed with fire shutters from the $2^{nd}$ floor to the atrium top, and the ground floor is allowed to open to the atrium; in this case, no smoke control is required. Strategy B is the atrium protection approach, with smoke control provided in accordance with NFPA 92B; in this case, no atrium floor is enclosed. Strategy C is the atrium protection approach, in which some of the upper atrium floors are enclosed (the case of the top atrium floor being enclosed is evaluated in this study), and atrium smoke control is also provided to protect the lower atrium floors.

• International journal of advanced smart convergence
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• v.13 no.3
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• pp.367-375
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• 2024

Draft curtains are an important tool to reduce the spread of fire smoke in buildings. This paper mainly studies the influence of draft curtains on smoke spread in a hospital outpatient building with a spacious hall. The outpatient building of a county hospital in China is taken as the research object, and a fire simulation model is established based on PyroSim software. Four scenarios are designed: no draft curtains in the hall, draft curtains with a length of 1.5m in the hall, draft curtains with a length of 2.0m in the hall, and draft curtains with a length of 2.5m in the hall. At the same time, considering the worst situation, only the main emergency exit is opened, while the remaining emergency exits and windows are all closed, and the fire-fighting facilities are not activated. The detection point is set at the open emergency exit, 1.8m above the ground. Through the simulation of four scenarios, the effect of draft curtains on smoke spread is discussed from four aspects: smoke layer height, temperature, visibility, and CO concentration. The results show that draft curtains have a significant impact on the spread of smoke in a hospital outpatient building with a spacious hall. The longer the draft curtains are, the better the smoke-blocking effect. It should be noted that in the actual design, the length of the draft curtains should be considered without affecting the evacuation of personnel.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.398-403
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• 2009

The theoretical bases on characteristics of heat release rate in compartment of building for scenario of smoke management are introduced and the numerical applications to simple compartment model are carried out. The growth stage which is important for smoke management design is modelled as t-squared fire curve including fire growth coefficient with related to growth rate. The conditions for the happening of flashover is presented such as $600^{\circ}C$ of temperature or $20kW/m^2$ of radiation heat flux. After the flashover happen, the fire in compartment changes to fully developed fire having the characteristics of ventilation-controlled fire. As the result of numerical analysis to simple compartment model, the time to reach 900K under ceiling for condition of medium growth is twice for condition of fast growth.

• Fire Science and Engineering
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• v.20 no.4 s.64
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• pp.91-97
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• 2006

This study was executed to review feasibility on the calculation of critical velocity with a reduced model of an actual tunnel in order to establish the optimum fire protection system for a fire in road tunnels. In a scaled model about 1/29 of an actual tunnel based on the Froude scaling, critical velocity was calculated by visualizing smoke flow and analyzing correlation with temperature. In the experiment, critical velocities at which smoke backflow length became zero showed a small difference within about 5% compared to results calculated by the Kennedy formula, and the relation between smoke flow and temperature distribution appeared similarly without getting greatly influenced by changes in fire intensity.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.1
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• pp.65-70
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• 2023

In this paper, we used a deep learning model to detect and segment flame and smoke in real time from fires. To this end, well known U-NET was used to separate and divide the flame and smoke of the fire using multi-class. As a result of learning using the proposed technique, the values of loss error and accuracy are very good at 0.0486 and 0.97996, respectively. The IOU value used in object detection is also very good at 0.849. As a result of predicting fire images that were not used for learning using the learned model, the flame and smoke of fire are well detected and segmented, and smoke color were well distinguished. Proposed method can be used to build fire prediction and detection system.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.111-112
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• 2020

As buildings in South Korea become more skyscrapers, the risk of fire is also emerging. Thus, regulations, regulations, and guidelines are being improved to prevent the spread of smoke in the event of a fire in high-rise buildings, but research on smoke flow and pressure distribution in vertical spaces is insufficient. Therefore, in this study, the temperature of each floor in the vertical space according to the size of the fire is measured through the miniature model experiment, and the pressure difference is calculated to establish the basic data for the improvement of the performance of domestic air supply facilities in the future. Thus, a scale model of one-sixth the size of the actual building was produced to measure the temperature, and the pressure difference was derived by substituting the value for the expression. The pressure difference varies depending on the size of the cause of the fire, and it is believed that the differential pressure and conditions of the building should be taken into account before calculating the supply volume for the analysis of the pressure difference according to the size of the cause of the fire in the event of fire.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.4
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• pp.344-350
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• 2006

The present study investigates the characteristics of fire-driven heat flows and gas concentration in a compartment fire by using the modified VHS model (MVHS). The main idea of this model is to add some source terms for combustion products and oxygen consumption to the original VHS model for providing more accurate and useful information on gas concentration distributions as well as thermal fields. It is found that the present MVHS model shows fairly good agreement with the experimental data and the eddy breakup combustion model. The tilting angle of fire plume calculated by MVHS is larger than that of EBU model because the fire source of VHS is affected by ventilating flow less than EBU. However, this discrepancy is apparently reduced in the downstream region of fire source.

• Journal of the Society of Naval Architects of Korea
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• v.47 no.3
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• pp.454-461
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• 2010

The new SOLAS regulation permits the alternative design approach for the approval of designs which deviate from those where prescriptive rules apply. The new approach is being promoted by recent advances of noble designs such as those employing large public spaces in passenger ships. From the respect of fire safety, it is needed to show that the level of safety of new design is equivalent to what can be achieved from the prescriptive rules where the fire simulation is regarded to be the essential tool. This paper provides an overview of the process of performance-based design of the smoke extraction system in a cafeteria of a ROPAX. FDS, a CFD fire simulation software is used to show that the field-model software can improve the fire safety over what are expected from prescriptive rule sets or zone-model application.

• Korean Journal of Remote Sensing
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• v.38 no.5_3
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• pp.967-977
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• 2022

The occurrence and intensity of wildfires are increasing with climate change. Emissions from forest fire smoke are recognized as one of the major causes affecting air quality and the greenhouse effect. The use of satellite product and machine learning is essential for detection of forest fire smoke. Until now, research on forest fire smoke detection has had difficulties due to difficulties in cloud identification and vague standards of boundaries. The purpose of this study is to detect forest fire smoke using Level 1 and Level 2 data of Geostationary Environment Monitoring Spectrometer (GEMS), a Korean environmental satellite sensor, and machine learning. In March 2022, the forest fire in Gangwon-do was selected as a case. Smoke pixel classification modeling was performed by producing wildfire smoke label images and inputting GEMS Level 1 and Level 2 data to the random forest model. In the trained model, the importance of input variables is Aerosol Optical Depth (AOD), 380 nm and 340 nm radiance difference, Ultra-Violet Aerosol Index (UVAI), Visible Aerosol Index (VisAI), Single Scattering Albedo (SSA), formaldehyde (HCHO), nitrogen dioxide (NO₂), 380 nm radiance, and 340 nm radiance were shown in that order. In addition, in the estimation of the forest fire smoke probability (0 ≤ p ≤ 1) for 2,704 pixels, Mean Bias Error (MBE) is -0.002, Mean Absolute Error (MAE) is 0.026, Root Mean Square Error (RMSE) is 0.087, and Correlation Coefficient (CC) showed an accuracy of 0.981.