Study on Heat Release Rate Model in Steel Bridge Highway Fire

With the rapid development of the highway industry, the steel structure as the main Long Span Bridge build more and more, the highways are carrying more and more traffic than before and vehicle fires are becoming more frequent. This paper, (which is based on previous literature on the behavior of fire, and the main research method of fire heat release-rate) proposes a mathematical model for the heat release-rate of highway fires. Using the fire numerical simulation software FDS to do an analysis of the temperature field of an open space formed by a 300 mw heat release-rate reveals that the maximum temperature decrease is non-linear when the height increase.

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Numerical Simulation on Spreading Characteristic of Coach Fire

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.518-523.1269 ◽

2012 ◽

Vol 518-523 ◽

pp. 1269-1272 ◽

Cited By ~ 3

Author(s):

Liang Yi ◽

Jie Chen

Keyword(s):

Fluid Dynamics ◽

Numerical Simulation ◽

Computational Fluid Dynamics ◽

Heat Release ◽

Heat Release Rate ◽

Fire Protection ◽

Release Rate ◽

Software Package ◽

Maximum Temperature ◽

Peak Heat Release Rate

The aim of this work is to study the burning characteristics of coach fire. With application of computational fluid dynamics (FDS software package), coach fires caused by arson are simulated under different ventilation conditions. Variation of heat release rate (HRR) and distribution of temperature are analyzed. Peak heat release rate of coach fire caused by arson in passenger carriage can reach about 24 MW and maximum temperature in the carriage is over 1000 °C. Results of this study can be referred for fire protection and rescue design of coach.

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Characteristics of fire in high-speed train carriages

Journal of Fire Sciences ◽

10.1177/0734904119894527 ◽

2019 ◽

Vol 38 (1) ◽

pp. 75-95

Author(s):

Haiquan Bi ◽

Yuanlong Zhou ◽

Honglin Wang ◽

Qilin Gou ◽

Xiaoxia Liu

Keyword(s):

Numerical Simulation ◽

Heat Release ◽

Heat Release Rate ◽

Release Rate ◽

Ignition Temperature ◽

High Speed ◽

Rapid Development ◽

Longitudinal Direction ◽

High Speed Train ◽

Fire Source

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.

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An improved model for estimating heat release rate in horizontal cable tray fires in open space

Journal of Fire Sciences ◽

10.1177/0734904118769810 ◽

2018 ◽

Vol 36 (3) ◽

pp. 275-290 ◽

Cited By ~ 5

Author(s):

Xianjia Huang ◽

He Zhu ◽

Lan Peng ◽

Zihui Zheng ◽

Wuyong Zeng ◽

...

Keyword(s):

Heat Release ◽

Heat Release Rate ◽

Release Rate ◽

Large Scale ◽

Open Space ◽

Local Error ◽

Bench Scale ◽

Improved Model ◽

Cable Fire ◽

Fire Experiments

Electric cable fires in nuclear power plants could be disastrous and have to be studied carefully for safety and economic considerations. Based on the results of previous work on large-scale and bench-scale cable fire testing, the Flame Spread over Horizontal Cable Trays model was modified and improved to estimate the heat release rate of large-scale cable fires using bench-scale measured data. The heat release rate per unit area measured in the cone calorimeter experiment is taken as the input, to avoid introducing any prediction uncertainties caused by inconsistent values of the heat of combustion and char yield of the cable. Cable fire experiments with vertical stacks of trays with one to three layers of cables were conducted in open space to assess the accuracy of the improved model. In comparing with the experimental results, predictions using the improved model are encouraging. The local error of prediction is less than 15% and the global error lies between 19.2% and 35.7%. In addition, three cable tray fire experiments with data available in the literature were used to validate the improved model. It is shown that the improved model had good predictions for these cable tray fires.

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Fire Safety Assessment of Epoxy Composites Reinforced by Carbon Fibre and Graphene

Applied Composite Materials ◽

10.1007/s10443-020-09824-4 ◽

2020 ◽

Vol 27 (5) ◽

pp. 619-639 ◽

Cited By ~ 1

Author(s):

Qiangjun Zhang ◽

Yong C Wang ◽

Constantinos Soutis ◽

Colin G. Bailey ◽

Yuan Hu

Keyword(s):

Mechanical Properties ◽

Heat Conduction ◽

Carbon Fibre ◽

Heat Release ◽

Heat Release Rate ◽

Release Rate ◽

Structural Integrity ◽

Composite Panel ◽

Maximum Temperature ◽

In Fire

Abstract This paper presents a coupled numerical investigation to assess the reaction to fire performance and fire resistance of various types of epoxy resin (ER) based composites. It examines the fire response of carbon fibre (CF) reinforced ER (CF/ER), ER with graphene nanoplatelets (GNP/ER) and CF reinforced GNP/ER (CF/GNP/ER). Thermal, physical and pyrolysis properties are presented to assist numerical modelling that is used to assess the material ability to pass the regulatory vertical burn test for new aircraft structures and estimate in-fire and post-fire residual strength properties. Except for the CF/GNP/ER composite, all other material systems fail the vertical burn test due to continuous burning after removal of the fire source. Carbon fibres are non-combustible and therefore reduce heat release rate of the ER composite. By combining this property with the beneficial barrier effects of graphene platelets, the CF/GNP/ER composite with 1.5 wt% GNP and 50 wt% CF self-extinguishes within 15 s after removal of the burner with a relatively small burn length. Graphene drastically slows down heat conduction and migration of decomposed volatiles to the surface by creating improved char structures. Thus, graphene is allowing the CF/GNP/ER composite panel to pass the regulatory vertical burn test. Due to low heat conduction and reduced heat release rate, the maximum temperatures in the CF/GNP/ER composite are low so the composite material retains very high in-fire and post-fire mechanical properties, maintaining structural integrity. In contrast, temperatures in the CF/ER composite are much higher. At a maximum temperature of 86 °C, the residual in-fire tensile and compressive mechanical strengths of CF/GNP/ER are about 87% and 59% respectively of the ambient temperature values, compared to 70% and 21% respectively for the CF/ER composite that has a temperature of 140 °C at the same time (but the CF/ER temperature will be higher due to continuing burning). Converting mass losses of the composites into char depth, the post-fire mechanical properties of the CF/GNP/ER composite are about 75% of the ambient condition compared to about 68% for the CF/ER composite.

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Numerical investigation on the smoke behaviour and longitudinal temperature decay in tilted tunnel fire with portal sealing

Indoor and Built Environment ◽

10.1177/1420326x211034894 ◽

2021 ◽

pp. 1420326X2110348

Author(s):

Jiaxin Li ◽

Yanfeng Li ◽

Junmei Li ◽

Quan Yang

Keyword(s):

Heat Release ◽

Heat Release Rate ◽

Release Rate ◽

Temperature Rise ◽

Ventilation System ◽

Emergency Evacuation ◽

Maximum Temperature ◽

Tunnel Fire ◽

Temperature Decay ◽

Tunnel Portal

Blocking the tunnel portal is one strategy in railway tunnel firefighting. In order to evaluate the effect of tunnel portal sealing ratio on fire behaviour, Fire Dynamics Simulator (FDS) was used to simulate tilted tunnel fire with different slope angles varying from 0% to 5%, heat release rate varying from 10 to 50 MW and sealing ratios varying from 0% to 75%. Results show that the experimental data of the temperature distribution inside the tilted tunnel were in good agreement with the simulation results. Moreover, the ceiling temperature rise decreases along the tunnel with the increase of the tunnel portal sealing ratio at initial stage and then tends to stabilize because of less oxygen supply when the heat release rate is relatively large. The maximum temperature rise decays exponentially along the tunnel ceiling with distance. The current model for temperature decay beneath the tunnel ceiling was proposed to be modified by taking the tunnel entrance sealing ratio into account. The predictions by the modified model agree well with the experimental measurement. The results could provide practical information and knowledge in ventilation system design and emergency evacuation for inclined railway tunnels.

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