scholarly journals Research Regarding Analysis of the Target Safety Standard for Fire Resistance Design and its Mode of Expression - Estimation for the Safety Standard Targeted by the Verification Method for Fire Resistance Performance - Chapter 4 Identification of Localized Fire Source and Calculation of Heat Release Rate

2008 ◽  
Vol 27 (3) ◽  
pp. 372-417
Author(s):  
Akiko Natori
2011 ◽  
Vol 332-334 ◽  
pp. 1335-1338
Author(s):  
Shu Gan Li ◽  
Xiao Ning Jiao ◽  
Qing Long Jia

This paper demonstrates the combustibility of PI needle punched nonwovens by Cone Calorimeter. Ignition parameter, heat release parameters, smoke and toxicity parameters and mass loss parameters of the fabric were obtained from it. It was found that ignition time is 38 s; the peak of heat release rate is 65 kW/m2; total heat release is 7 MJ/m2; smoke release rate is 1.5 L/s; smoke factor is 1.3 MW/m2 and mass lose rate is 73.3%. Therefore the results show that PI needle punched nonwovens has excellent fire-resistance performance.


2014 ◽  
Vol 580-583 ◽  
pp. 2667-2670
Author(s):  
Pei Hong Zhang ◽  
Xiao Wei Lu ◽  
Xiao Ming Zhang

The phenomenon of ghosting fire development in underground confined space is simulated to analyze the impacts of ghosting fire generation via some conditions -- different air vent sizes and different fire source areas. FDS is used to establish a physical model of underground fire laboratory in Northeastern University, the simulation is conducted by setting two parameters, the air vent size and the fire source area. The fire heat release rate, temperature, concentration of CO, O2 are measured to analyze the case of ghosting fire generation in underground confined space with different air vent sizes and different fire source areas. It’s most likely to generate ghosting fire when the simulating parameter is that the air vent size is 0.4m × 0.4m and the fire source area is 0.96m2. The conclusion is that increasing the air vent size is not a simple ascending and descending relationship with the occurrence time and duration time of the ghosting fire. Increasing the fire source area can improve the fire heat release rate effectively, and promote the formation of ghosting fire.


2021 ◽  
Vol 21 (2) ◽  
pp. 65-71
Author(s):  
Seunggoo Kang ◽  
Yi Chul Shin

In this study, to allow the flashover to occur, combustion tests were conducted by setting the conditions of a fire source using a large-scale compartment and changing the opening condition. As a result, the inside temperature of the compartment was measured under the fire source conditions. Moreover, according to the “Handbook on Design Calculation &#x0004d;ethods of Fire Behavior” by the Architectural Institute of Japan, the validity of the heat release rate required for the flashover to occur was verified through the correlation between <math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>Q</mi><mrow><mi>F</mi><mi>O</mi></mrow></msub><mo>/</mo><msub><mi>Q</mi><mrow><mi>v</mi><mi>m</mi><mi>a</mi><mi>x</mi></mrow></msub></math> and <math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>A</mi><mi>T</mi></msub><msup><mrow><mo>(</mo><mi>k</mi><mi>p</mi><mi>c</mi><mo>)</mo></mrow><mrow><mn>1</mn><mo>/</mo><mn>2</mn></mrow></msup><mo>/</mo><msub><mi>c</mi><mrow><mi>P</mi></mrow></msub><mn>0</mn><mo>.</mo><mn>5</mn><mi>A</mi><msup><mi>H</mi><mrow><mn>1</mn><mo>/</mo><mn>2</mn></mrow></msup></math>.


2019 ◽  
Vol 37 (3) ◽  
pp. 213-235
Author(s):  
Yanqiu Chen ◽  
Dong Wang ◽  
Junmin Chen

Heat transfer and smoke flow filling progress in a super-high atrium is studied in this article. The influences of heat release rate and fire source height were considered. It was found that the fire smoke layer could not reach the top of the atrium when the heat release rate was very low and the fire source was located at the bottom of the atrium. The temperature of smoke layer interface and Δ Tmax were linearly positively related to Q2/3, while Δ Pmax was quadratically positively related to Q2/3. At the top of the atrium, the temperature rise and fire source height were consistent with the Boltzmann model. As the fire smoke rose with a velocity, a relatively low-pressure area was generated below. The pressure variation in this area was negatively index-related to the fire source height.


2019 ◽  
Vol 38 (1) ◽  
pp. 75-95
Author(s):  
Haiquan Bi ◽  
Yuanlong Zhou ◽  
Honglin Wang ◽  
Qilin Gou ◽  
Xiaoxia Liu

With the rapid development of high-speed railways, safety hazards presented by train fires cannot be ignored. An effective design for protection against fire in high-speed trains is essential to ensure passenger safety. In this study, the cone calorimeter and ignition temperature tester were used to carry out combustion experiments on materials constituting the main components of the train. The heat release rate, smoke yield, CO yield, and ignition temperature of combustible materials were tested. Based on the experimental data of material combustion, a numerical model of the high-speed train carriage fire was simulated. The accuracy of the numerical simulation was verified by drawing a comparison with the full-scale train fire experiment in existing literature. The numerical simulation results revealed that when the fire source is present at the corner of the carriage end door, the fire develops to the maximum possible extent in approximately 25 min, with a peak heat release rate of approximately 38.4 MW. Increase in the carriage fire heat release rate and breakage of windows occur almost simultaneously. Improvement of the fireproof performance of windows can inhibit and delay the carriage fire development. For the flashover of carriage fire, the spread speed of the flashover area in the longitudinal direction inside the carriage is approximately 1.9 m/s. The end door area furthest from the fire source in the carriage has strong flashover, while the flashover in other areas is weak.


2013 ◽  
Vol 295-298 ◽  
pp. 2287-2293
Author(s):  
Huai Bing Zheng ◽  
Xu Jian Peng ◽  
Min Xia Zhang ◽  
Lin Ju

On condition that the heat release rate is 50kW•m-2, the volume of a gas velocity is 24 L•s-1, the combustibility of Pinus koraiensis、Pinus sylvestris var. mongolica、Picea koraiensis、Larix gmelinii in Heilongjiang Province were determined systematically through the use of the controlled atmosphere tapered calorimeter. Through the comparative analysis of the heat release rate and the smoke production rate and some orther burning parameters of the barks and the withered leaves, combine the moisture content of barks and withered leaves of each species, evaluate the fire resistance of this four coniferous species. The results shown: the heat release rate, HRR; total heat release, THR; specific extinction area and smoke produce rate are higher in the barks and withered leaves of Picea koraiensis but the fire performance index is low, these instructions that the fireproof performance is worse in Pinus sylvestris var. mongolica; each Picea koraiensis burning indexs of the Larix gmelinii is lower or the lowest, both the smoke production rate, SPR and the heat release rate, HRR are slow, the fire performance index is high. However, its absolute moisture content and relative moisture content is the highest, it’s flammble.So,we conclude its fire-resistance performance is higher, we could choose it as the fire-preventing priority screening tree species; the flammability of Pinus koraiensis and Pinus sylvestris var. mongolica between the above two species. the combustion characteristics of trees is the result of multiple factor joint, The difference between the different research results is resulted in the choice of the indexs, so it’s urgent need to establish a comprehensive and integrated evaluation index system.


Author(s):  
Xianjia Huang ◽  
Kun Bi ◽  
Jun Xiao ◽  
Lan Peng ◽  
He Zhu ◽  
...  

Multi-layer cable tray fire has special burning characteristics that the cable flame spreads horizontally along cable tray and propagates vertically from bottom layer to upper layer at the same time. With respect of accuracy and speed of calculation, simulation of multi-layer cable tray fire remains a challenge for fire models. In this paper, a method is proposed to simulate multi-layer cable tray fire. By developing a more accurate fire source description, this method can provide accurate simulation for multi-layer cable tray fire rapidly. In this method, Firstly, the heat release rate of each burning cable tray is evaluated by FLASH-CAT model. Based on the results from FLASH-CAT, a more accurate fire source definition for multiple lay cable tray is developed for zone model. Taking account of each burning cable tray considered as one fire source point, zone model is applied to predict the fire dynamics process. In order to validate this method, four-layer cable tray fire experiments and replicated experiments were carried out in a confined compartment. The histories of mass loss rate of cable tray and temperatures at the middle of compartment were recorded during the cable fire. From the replicated experimental results of total mass loss rate, it is concluded that the four-layer cable tray fire experiment has good repetition in this scenario. Vertical temperature profile shows that the fire circumstance generated by multiple-layer cable tray burning can be divided into upper hot layer and lower cool layer, which conforms to the basic assumption of zone model. As a consequence, the zone model can be applied to simulating multiple-layer cable tray fire. By comparing the experimental total heat release rate with predictions, it is found that characteristics of multiple-layer cable tray fire are well captured. On account of good prediction on overall heat release rate for multi-layer cable tray fire, predicted heat release rate for each burning cable layer by FLASH-CAT model is believed to be reliable. Then, each burning cable layer is set as one fire source and the heat release rate of each burning cable layer is input into zone model, respectively. The comparisons between simulations and experimental data show that the predicted upper layer temperature and lower layer temperature agree well with experimental data. As a result, it can be concluded that this method provides reliable prediction for multiple-layer cable tray fire rapidly.


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