scholarly journals Study on Flame Spread Characteristics of Flame-Retardant Cables in Mine

2020 ◽  
Vol 2020 ◽  
pp. 1-7 ◽  
Author(s):  
Gao Ke ◽  
Liu Zimeng ◽  
Jia Jinzhang ◽  
Liu Zeyi ◽  
Aiyiti Yisimayili ◽  
...  
Keyword(s):  
Wind Speed ◽  
Flame Retardant ◽  
Fire Spread ◽  
Experimental Results ◽  
Experiment Platform ◽  
Mine Fires ◽  
Actual Environment ◽  
Combustion Experiment ◽  
Fire Loads ◽  
Cable Fire

Polymer combustion is an important factor in mine fires. Based on the actual environment in a mine tunnel, a cable combustion experiment platform was established to study the regularities of the cable fire spread speed and smoke temperature under different conditions, including various fire loads and ventilation speeds. The flame change and molten dripping behaviour during the fire spread process were also analyzed. The experimental results show that the flame-retardant cable can be ignited and continuously burnt at a certain wind speed, but the combustion can be restrained at high wind speed. The combustion speed of the flame-retardant cable is affected by the fire load and ventilation speed. The combustion droplets can change the shape of the flame, which can consequently ignite other combustible materials. The analysis of the experimental results provides an important basis for the prevention of tunnel fires.

Effects of Wind on the Heat Flow of FPSO Topsides Subject to Fire: An Experimental and Numerical Study

2010 ◽  
Author(s):  
Joon Young Yoon ◽  
Seong Hwan Kim ◽  
Gwon Cheol Yu ◽  
Jung Kwan Seo ◽  
Bong Ju Kim ◽  
...  
Keyword(s):  
Thermal Diffusion ◽  
Numerical Study ◽  
Wind Tunnel Test ◽  
Experimental Results ◽  
Test Facility ◽  
Test Model ◽  
Cfd Simulations ◽  
Fire Engineering ◽  
Diffusion Characteristics ◽  
Fire Loads

The aim of this paper is to examine the effect of wind on the thermal diffusion characteristics of floating production storage and offloading (FSPO) topside models subject to fire. It is motivated by the need to identify the fire loads on FPSO topsides, taking into account the effects of wind speed and direction. The results of an experimental and numerical study undertaken for these purposes are reported here. This paper is part of Phase II of the joint industry project on explosion and fire engineering of FPSOs (EFEF JIP) [1]. An experiment was performed on a 1/14-scale FPSO topside model using a wind tunnel test facility. The locations of the heat source of the fire were varied, as were the speed and direction of the wind, and the temperature distribution was measured. Computational fluid dynamics (CFD) simulations using the ANSYS CFX program were performed on the test model, with the results obtained compared with the experimental results. It is concluded that wind has a significant effect on the thermal diffusion characteristics of the test model and that the CFD simulations are in good agreement with the experimental results. The insights developed in this study will be very useful for the fire engineering of FPSO topsides.

Experimental and Theoretical Investigation of Performance of a Solar Chimney Model, Part I: Experimental Investigation

2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Essaied M Shuia ◽  
Bashir H Arebi ◽  
Ibrahim A abuashe
Keyword(s):  
Experimental Data ◽  
Wind Speed ◽  
Solar Radiation ◽  
Air Temperature ◽  
Solar Collector ◽  
Experimental Results ◽  
Internal Diameter ◽  
Solar Chimney ◽  
Air Velocity ◽  
Collector Temperature

This paper presents the experimental data that was collected from small pilot solar chimney. The experimental data together with ambient conditions are used to evaluate the performance and study the behavior of the solar chimney; this data will be used for comparison with theoretical models in another paper [part II). The solar chimney prototype was designed and constructed at the Subrata Faculty of Engineering-Libya. The data were collected over several days of June 2011. The solar chimney system contains two main components; the solar collector and the solar chimney. The solar collector root‘ has a circular area of126 m3, the solar chimney is a PVC tube with internal diameter of 0.2 m and the total height of chimney is 9.3 m. The measurements include the intensity of solar radiation inside/outside the collector, temperature and velocity of air at the entrance of the chimney, temperature and speed of wind outside the collector, temperature of the ground inside collector al1d temperature measurements of air at speci?c points at different levels throughout the collector. Solar irradiance was found to affect the chimney temperature and subsequently affects chimney air velocity. The experimental results showed that temperature differences of (30 - 45°C) were recorded between the ambient temperature and that of air inside the chimney in the middle of the day, where the highest air temperature of 73.4°C was recorded at the entrance of the solar chimney. The maximum air velocity of 3.6 m/s was recorded inside the solar chimney at noon on 9 June. Wind speed outside the collector had a small effect on the speed of the air inside the chimney and tends to change slightly, hence, can neglect influence of wind speed on the performance of the system. Also the experimental results indicate that such type of system can trap a suf?cient amount of solar radiation, which elevates the air temperature to a suf?cient value able to generate enough air ?ow to operate a wind turbine to produce electricity; this means the solar chimney system for electricity production can work in the north-western part of Libya in the summer time at least.

Project Vesta: Fire in Dry Eucalypt Forest

2008 ◽  
Author(s):  
JS Gould ◽  
WL McCaw ◽  
NP Cheney ◽  
PF Ellis ◽  
IK Knight ◽  
...  
Keyword(s):  
Wind Speed ◽  
Fire Spread ◽  
Fire Behaviour ◽  
Understorey Vegetation ◽  
Eucalypt Forest ◽  
Age Related ◽  
Vegetation Structures ◽  
Eucalypt Forests ◽  
The Relationship ◽  
New Algorithms

Project Vesta was a comprehensive research project to investigate the behaviour and spread of high-intensity bushfires in dry eucalypt forests with different fuel ages and understorey vegetation structures. The project was designed to quantify age-related changes in fuel attributes and fire behaviour in dry eucalypt forests typical of southern Australia. The four main scientific aims of Project Vesta were: To quantify the changes in the behaviour of fire in dry eucalypt forest as fuel develops with age (i.e. time since fire); To characterise wind speed profiles in forest with different overstorey and understorey vegetation structure in relation to fire behaviour; To develop new algorithms describing the relationship between fire spread and wind speed, and fire spread and fuel characteristics including load, structure and height; and to develop a National Fire Behaviour Prediction System for dry eucalypt forests. These aims have been addressed through a program of experimental burning and associated studies at two sites in the south-west of Western Australia.

Fire-growth modelling using meteorological data with random and systematic perturbations

2007 ◽  
Vol 16 (2) ◽  
pp. 174 ◽  
Author(s):  
Kerry Anderson ◽  
Gerhard Reuter ◽  
Mike D. Flannigan
Keyword(s):  
Wind Speed ◽  
Growth Model ◽  
Forest Fires ◽  
Meteorological Data ◽  
Random Perturbation ◽  
Weather Forecast ◽  
Fire Spread ◽  
Fire Growth ◽  
Hourly Data ◽  
Systematic Perturbation

The focus of this investigation is to quantify the effects of perturbations in the meteorological data used in a fire-growth model. Observed variations of temperature, humidity, wind speed, and wind direction are applied as perturbations to hourly values within a simulated weather forecast to produce several forecasts. In turn, these are used by a deterministic eight-point fire-growth model to produce an ensemble of possible final fire perimeters. Two studies were conducted to assess the value of applying perturbations. In the first study, fire growth using detailed, one-minute data was compared to growth based on the more commonly used hourly data. Results showed that the detailed weather produced fire growth larger and wider than the hourly based data. By applying perturbations, variations in the flank and back-fire spread were captured by the random-perturbation model while the forward spread fell within the 20 to 30% probability prediction. A sensitivity analysis based on the observed variations showed that wind speed accounted for a 44% difference in area burned, while temperature accounted for only a 16% difference. In the second study, case studies were conducted on four observed forest fires in Wood Buffalo National Park. Results showed that daily fire-growth predictions using simulated weather forecasts over-predicted fire growth using actual hourly weather observations by 27%. Systematic-perturbation models best compensated for this with most fire growth falling within the predicted range of the models (52 out of 63 days).

A cellular automata model to link surface fires to firebrand lift-off and dispersal

2013 ◽  
Vol 22 (4) ◽  
pp. 428 ◽  
Author(s):  
Holly A. Perryman ◽  
Christopher J. Dugaw ◽  
J. Morgan Varner ◽  
Diane L. Johnson
Keyword(s):  
Wind Speed ◽  
Wildland Fire ◽  
Fire Spread ◽  
Fuel Moisture ◽  
Fuel Loading ◽  
Cellular Automata Model ◽  
Rate Of Spread ◽  
Lift Off ◽  
Fuel Moisture Content ◽  
Spot Fires

In spite of considerable effort to predict wildland fire behaviour, the effects of firebrand lift-off, the ignition of resulting spot fires and their effects on fire spread, remain poorly understood. We developed a cellular automata model integrating key mathematical models governing current fire spread models with a recently developed model that estimates firebrand landing patterns. Using our model we simulated a wildfire in an idealised Pinus ponderosa ecosystem. Varying values of wind speed, surface fuel loading, surface fuel moisture content and canopy base height, we investigated two scenarios: (i) the probability of a spot fire igniting beyond fuelbreaks of various widths and (ii) how spot fires directly affect the overall surface fire’s rate of spread. Results were averages across 2500 stochastic simulations. In both scenarios, canopy base height and surface fuel loading had a greater influence than wind speed and surface fuel moisture content. The expected rate of spread with spot fires occurring approached a constant value over time, which ranged between 6 and 931% higher than the predicted surface fire rate of spread. Incorporation of the role of spot fires in wildland fire spread should be an important thrust of future decision-support technologies.

Experimental Study of Cable Fire Spread in Electronic Cabinet

2013 ◽  
Vol 664 ◽  
pp. 964-969
Author(s):  
Chao Zhou ◽  
Xin Qun Wang ◽  
Jun Qin ◽  
Lu Yi Chen ◽  
Gang Xuan Lao ◽  
...  
Keyword(s):  
Experimental Study ◽  
Fire Spread ◽  
Ventilation Rate ◽  
Electronic Cabinet ◽  
Cable Fire ◽  
Real Scale ◽  
Fire Experiments

Three cases of cables fire experiments with different ventilation rate in real scale electronic cabinet have been carried out. In each experiment, five cables with 14mm in out diameter and four copper conductors with 1650mm in length were used. the insulation and cover of the cables was combustible .Temperature of the fire cables, CO ,O2as well as temperature in different location in the center of the cabinet in the fire cabinet were measured as a function of time. The key role of the ventilation rate on the temperature in the center of the cabinet and the concentration of CO and O2were clearly shown, but the influence on fire spread of cable fire was not so much significantly.

Flame retardance of modified graphene to pure cotton fabric

2017 ◽  
Vol 36 (2) ◽  
pp. 111-128 ◽  
Author(s):  
Hong Liu ◽  
Yang Du ◽  
Guohai Yang ◽  
Guoqing Zhu ◽  
Yunji Gao ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Flame Retardant ◽  
Cotton Fabric ◽  
Combustion Process ◽  
Experimental Results ◽  
Graphene Oxides ◽  
Nitrogen Doped ◽  
Nitrogen Doped Graphene ◽  
Doped Graphene ◽  
Phosphorus Doped

Phosphorus- and nitrogen-doped graphene oxides are conveniently obtained by the modification of as-prepared graphene oxide and characterized by scanning electron microscopy, X-ray powder diffraction, Fourier-transform infrared, and ultraviolet–visible spectra. The combustion performances of pure cotton fabric, respectively, enriched with graphene oxide, phosphorus-doped graphene oxide, and nitrogen-doped graphene oxides, are tested and evaluated. The results show that phosphorus-doped graphene oxide acts as the most promising flame retardant, which can effectively reduce the burning rate and heat release rate of the combustion process, with excellent smoke suppression effect. Based on the relevant parameters obtained from the experimental results of phosphorus-doped graphene oxide, Simtec simulation is operated to demonstrate vertical combustion of thin fabric before and after flame-retardant treatment, and the results are consistent with the trend of the experimental results and suggest a magnifying effect of phosphorus-doped graphene oxide.

scholarly journals Combustion properties and thermal decomposition kinetics of flame retardant silk fabrics treated by phytic acid and silica sols

2018 ◽  
Vol 22 (4) ◽  
pp. 1665-1671 ◽  
Author(s):  
Yun-Bo Chen ◽  
Chun Liu ◽  
Shao-Li Zhang ◽  
Guo-Qiang Chen ◽  
Tie-Ling Xing
Keyword(s):  
Thermal Decomposition ◽  
Flame Retardant ◽  
Phytic Acid ◽  
Kinetics Model ◽  
Combustion Properties ◽  
Before And After ◽  
Combustion Experiment ◽  
Silk Fabrics ◽  
Silica Sols ◽  
Kinetics Of

In order to obtain the flame retardant silk fabric, silica sols and phytic acid were prepared and applied to the silk fabrics. Vertical combustion experiment, thermogravimetric analysis, Fourier transform infrared spectra and smoke density test were used to investigate the combustion behavior, thermal property, and kinetics model of silk fabrics before and after flame retardant finish. The results showed that the sol coating on silk fabrics could increase the carbon residue and hinder the spread of flame when burning, and the tensile strength of treated silk was slightly damaged. Furthermore, the kinetics model of silk thermal decomposition conformed to Avrami-Erofeev model.

scholarly journals Experimental and Numerical Studies on Major Pyrolysis Properties of Flame Retardant PVC Cables Composed of Multiple Materials

Materials ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1712 ◽  
Author(s):  
Sun-Yeo Mun ◽  
Cheol-Hong Hwang
Keyword(s):  
Sensitivity Analysis ◽  
Flame Retardant ◽  
Thermo Gravimetric Analysis ◽  
Fire Spread ◽  
Reference Temperature ◽  
Gravimetric Analysis ◽  
Fire Dynamics ◽  
Cable Structure ◽  
Pyrolysis Reaction ◽  
Multiple Materials

Flame retardant cables were investigated using thermo-gravimetric analysis to measure the reference temperature and reference rate required for a fire spread simulation using a Fire Dynamics Simulator (FDS). Sensitivity analysis was also performed to understand the effects of the reference temperature and rate on the pyrolysis reactions. A two-step pyrolysis reaction was typically observed regardless of the cable type, and each pyrolysis reaction could be attributed to single or multiple components depending on the cable type and reaction order. Although the structures, compositions, and insulation performances of the cables differed considerably, the reference temperatures of the two-step pyrolysis reaction were extremely similar regardless of the cable type. Conversely, the reference rates of the different types of cables varied significantly. The sensitivity analysis results indicate that the mean values of the reference temperature and rate are sufficient to simulate the pyrolysis reactions of flame retardant cables. The results obtained herein also suggest that the heat transfer and pyrolysis reaction path associated with the multi-layered cable structure may be more important for accurately determining the ignition and fire spread characteristics, which are attributable to differences in cable structure, composition, and insulation performance.

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