Journal articles: 'Flame spread Fire'

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Yedinak, Kara M., Jack D. Cohen, Jason M. Forthofer, and Mark A. Finney. "An examination of flame shape related to convection heat transfer in deep-fuel beds." International Journal of Wildland Fire 19, no. 2 (2010): 171. http://dx.doi.org/10.1071/wf07143.

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Fire spread through a fuel bed produces an observable curved combustion interface. This shape has been schematically represented largely without consideration for fire spread processes. The shape and dynamics of the flame profile within the fuel bed likely reflect the mechanisms of heat transfer necessary for the pre-heating and ignition of the fuel during fire spread. We developed a simple laminar flame model for examining convection heat transfer as a potentially significant fire spread process. The flame model produced a flame profile qualitatively comparable to experimental flames and similar to the combustion interface of spreading fires. The model comparison to flame experiments revealed that at increasing fuel depths (>0.7 m), lateral flame extension was increased through transition and turbulent flame behaviour. Given previous research indicating that radiation is not sufficient for fire spread, this research suggests that flame turbulence can produce the convection heat transfer (i.e. flame contact) necessary for fire spread particularly in vertically arranged, discontinuous fuels such as shrub and tree canopies.

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Wotton, B. M., R. S. McAlpine, and M. W. Hobbs. "The effect of fire front width on surface fire behaviour." International Journal of Wildland Fire 9, no. 4 (1999): 247. http://dx.doi.org/10.1071/wf00021.

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To determine the effect of fire front width on surface fire spread rates, a series of simultaneously ignited experimental fires was carried out in a pine plantation. Fires were ignited in plots with widths ranging from 0.5 m to 10 m and were burned in low wind conditions. Flame lengths were small in all fires, ranging from 20 cm to 60 cm. Since pre-heating of the forest litter from flame radiation is assumed to be an important mechanism in the spread of low intensity, low wind surface fires, it then follows that the width of a flaming front should effect on the heating of the fuel to ignition temperatures. Total flame radiation was also measured at a point 50 cm ahead of the advancing flame front for a number of the fires. Experimental results indicate that a flame radiation measured ahead of the fire stays fairly constant once the flame width is between 2 and 5 m. Theoretical flame radiation calculations confirm this trend. Rates of spread between the 5 and 10 metre width fires also appear to be similar; this indicates that, for the type of fires studied, once flame width is greater than about 2 m, radiation from any extra width of fire front has little effect on spread rate.

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Finney, Mark A., Jack D. Cohen, Isaac C. Grenfell, and Kara M. Yedinak. "An examination of fire spread thresholds in discontinuous fuel beds." International Journal of Wildland Fire 19, no. 2 (2010): 163. http://dx.doi.org/10.1071/wf07177.

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Many fuel beds, especially live vegetation canopies (conifer forests, shrub fields, bunch-grasses) contain gaps between vegetation clumps. Fires burning in these fuel types often display thresholds for spread that are observed to depend on environmental factors like wind, slope, and fuel moisture content. To investigate threshold spread behaviours, we conducted a set of laboratory burn experiments in artificial fuel beds where gap structure, depth, and slope were controlled. Results revealed that fire spread was limited by gap distance and that the threshold distance for spread was increased for deeper fuel beds and steeper slopes. The reasons for this behaviour were found using a high-speed thermal camera. Flame movements recorded by the camera at 120 Hz suggested fuel particles experience intermittent bathing of non-steady flames before ignition and that fuel particles across the gap ignited only after direct flame contact. The images also showed that the flame profile within the fuel bed expands with height, producing greater horizontal flame displacement in deeper beds. Slope, thus, enhances spread by increasing the effective depth in the uphill direction, which produces wider flames, and thereby increases the potential flame contact. This information suggests that fire spread across discontinuous fuel beds is dependent on the vertical flame profile geometry within the fuel bed and the statistical properties of flame characteristics.

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Delichatsios, M. A. "Basic Polymer Material Properties for Flame Spread." Journal of Fire Sciences 11, no. 4 (July 1993): 287–95. http://dx.doi.org/10.1177/073490419301100401.

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We present and demonstrate the application of a systematic methodology for predicting fire spread and growth and for a relative fire hazard classification of materials for any scale and fire environment. This methodol ogy consists of three steps: (1) select laboratory test methods to perform flam mability measurements; (2) based on these measurements, obtain key flamma bility material properties which are precisely defined in this work; and (3) use these properties in a mathematical model of fire spread and growth to predict fire hazards. The complementary test methods we have selected and used are: (a) a general flammability test apparatus (such as NIST or FMRC) [1,2] modified to also provide pyrolysis measurements in an inert N2 atmosphere; (b) the Limited Oxygen Index (LOI) apparatus, which is used here as a tool for ob taining properties needed for creeping flame spread and extinction, including vitiated environments; and (c) a solid material smoke-point height apparatus [8], which is used to characterize the smokiness of the burning material needed to determine the radiation and smoke yield for arbitrary fire situations (wall fires, pool fires or ceiling fires) [8]. The use and proper interpretation of the Limited Oxygen Index apparatus can replace the LIFT [10] apparatus for deter mining in a more accurate and direct way the material properties required for creeping (vertical downward, lateral, horizontal) flame spread. The present methodology has been compared well with experiments in this work and else where [9], and it has been used to predict critical conditions for fire spread [11], not empirically as it is usually done, but based on first principles of fire spread, fire growth and burning, together with material flammability properties syste matically deduced from small-scale test measurements.

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Streeks, Tamara J., M. Keith Owens, and Steve G. Whisenant. "Examining fire behavior in mesquite - acacia shrublands." International Journal of Wildland Fire 14, no. 2 (2005): 131. http://dx.doi.org/10.1071/wf03053.

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The vegetation of South Texas has changed from mesquite savanna to mixed mesquite–acacia (Prosopis–Acacia) shrubland over the last 150 years. Fire reduction, due to lack of fine fuel and suppression of naturally occurring fires, is cited as one of the primary causes for this vegetation shift. Fire behavior, primarily rate of spread and fire intensity, is poorly understood in these communities, so fire prescriptions have not been developed. We evaluated two current fire behavior systems (BEHAVE and the CSIRO fire spread and fire danger calculator) and three models developed for shrublands to determine how well they predicted rate of spread and flame length during three summer fires within mesquite–acacia shrublands. We also used geostatistical analyses to examine the spatial pattern of net heat, flame temperature and fuel characteristics. The CSIRO forest model under-predicted the rate of fire spread by an average of 5.43 m min−1 and over-predicted flame lengths by 0.2 m while the BEHAVE brush model under-predicted rate of spread by an average of 6.57 m min−1 and flame lengths by an average of 0.33 m. The three shrubland models did not consistently predict the rate of spread in these plant communities. Net heat and flame temperature were related to the amount of 10-h fuel on the site, but were not related to the cover of grasses, forbs, shrubs, or apparent continuity of fine fuel. Fuel loads were typical of South Texas shrublands, in that they were uneven and spatially inconsistent, which resulted in an unpredictable fire pattern.

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Cruz, Miguel G., Richard J. Hurley, Rachel Bessell, and Andrew L. Sullivan. "Fire behaviour in wheat crops – effect of fuel structure on rate of fire spread." International Journal of Wildland Fire 29, no. 3 (2020): 258. http://dx.doi.org/10.1071/wf19139.

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A field-based experimental study was conducted in 50×50m square plots to investigate the behaviour of free-spreading fires in wheat to quantify the effect of crop condition (i.e. harvested, unharvested and harvested and baled) on the propagation rate of fires and their associated flame characteristics, and to evaluate the adequacy of existing operational prediction models used in these fuel types. The dataset of 45 fires ranged from 2.4 to 10.2kmh−1 in their forward rate of fire spread and 3860 and 28000 kWm−1 in fireline intensity. Rate of fire spread and flame heights differed significantly between crop conditions, with the unharvested condition yielding the fastest spreading fires and tallest flames and the baled condition having the slowest moving fires and lowest flames. Rate of fire spread in the three crop conditions corresponded directly with the outputs from the models of Cheney et al. (1998) for grass fires: unharvested wheat → natural grass; harvested wheat (~0.3m tall stubble) → grazed or cut grass; and baled wheat (<0.1m tall stubble) → eaten-out grass. These models produced mean absolute percent errors between 21% and 25% with reduced bias, a result on par with the most accurate published fire spread model evaluations.

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Bradstock, RA, and AM Gill. "Fire in Semiarid, Mallee Shrublands - Size of Flames From Discrete Fuel Arrays and Their Role in the Spread of Fire." International Journal of Wildland Fire 3, no. 1 (1993): 3. http://dx.doi.org/10.1071/wf9930003.

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Aspects of flammability of the major fuel arrays in a mallee shrubland community, and the basis for fire-spread in these discrete fuels, are examined and discussed. Relationships between plant size and weight of litter (shrubs and mallee eucalypts) or grass hummocks (Triodia irritans) were studied. Hummock mass was a function of hummock diameter and height. On ignition, maximum flame length was related to hummock height and diameter. For mallee eucalypts the mass of litter beneath individual plants was related to the diameter of the litter bed. Flame length was also related to litter bed diameter. In other species of shrubs, fires were not sustained independently. We hypothesize that T. irritans will play a major role in fire spread in communities because flames from hummocks will have the greatest ability to bridge gaps between fuel arrays (flames longer than in eucalypts). Size of hummocks will have an important bearing on propagation of fire across fuel-gaps. By contrast, the main role of eucalypts in fire-spread may be as a source of burning brands which initiate spot fires. There is scope to understand fire-spread in these communities on the basis of flame lengths (in conjunction with plant size) in relation to wind.

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Ke, Gao, Liu Zimeng, Jia Jinzhang, Liu Zeyi, Aiyiti Yisimayili, Qi Zhipeng, Wu Yaju, and Li Shengnan. "Study on Flame Spread Characteristics of Flame-Retardant Cables in Mine." Advances in Polymer Technology 2020 (February 10, 2020): 1–7. http://dx.doi.org/10.1155/2020/8765679.

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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.

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Wotton, B. Mike, James S. Gould, W. Lachlan McCaw, N. Phillip Cheney, and Stephen W. Taylor. "Flame temperature and residence time of fires in dry eucalypt forest." International Journal of Wildland Fire 21, no. 3 (2012): 270. http://dx.doi.org/10.1071/wf10127.

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Temperature profiles of flames were measured using arrays of thermocouples on towers located in experimental bushfires of varying intensity, carried out in dry eucalypt forest of different fuel age and structure. In-fire video of flame-front passage and time series data from very fine exposed thermocouples were used to estimate the duration of passage of the main flaming front in these experimental fires. Flame temperature measured at points within the flame was found to vary with height; maximum flame temperature was greater in the tall shrub fuel than in the low shrub fuel sites. A model to estimate flame temperature at any height within a flame of a specific height was developed. The maximum flame temperature observed was ~1100°C near the flame base and, when observation height was normalised by flame height, flame temperature exponentially decreased to the visible flame tip where temperatures were ~300°C. Maximum flame temperature was significantly correlated with rate of spread, fire intensity, flame height and surface fuel bulk density. Average flame-front residence time for eucalypt forest fuels was 37 s and did not vary significantly with fine fuel moisture, fuel quantity or bulk density.

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Butler, B., C. Teske, D. Jimenez, J. O'Brien, P. Sopko, C. Wold, M. Vosburgh, B. Hornsby, and E. Loudermilk. "Observations of energy transport and rate of spreads from low-intensity fires in longleaf pine habitat – RxCADRE 2012." International Journal of Wildland Fire 25, no. 1 (2016): 76. http://dx.doi.org/10.1071/wf14154.

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Wildland fire rate of spread (ROS) and intensity are determined by the mode and magnitude of energy transport from the flames to the unburned fuels. Measurements of radiant and convective heating and cooling from experimental fires are reported here. Sensors were located nominally 0.5 m above ground level. Flame heights varied from 0.3 to 1.8 m and flaming zone depth varied from 0.3 to 3.0 m. Fire ROS derived from observations of fire transit time between sensors was 0.10 to 0.48 m s–1. ROS derived from ocular estimates reached 0.51 m s–1 for heading fire and 0.25 m s–1 for backing fire. Measurements of peak radiant and total energy incident on the sensors during flame presence reached 18.8 and 36.7 kW m–2 respectively. Peak air temperatures reached 1159°C. Calculated fire radiative energy varied from 7 to 162 kJ m–2 and fire total energy varied from 3 to 261 kJ m–2. Measurements of flame emissive power peaked at 95 kW m–2. Average horizontal air flow in the direction of flame spread immediately before, during, and shortly after the flame arrival reached 8.8 m s–1, with reverse drafts of 1.5 m s–1; vertical velocities varied from 9.9 m s–1 upward flow to 4.5 m s–1 downward flow. The observations from these fires contribute to the overall understanding of energy transport in wildland fires.

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11

Fernandes, Paulo M., Hermínio S. Botelho, Francisco C. Rego, and Carlos Loureiro. "Empirical modelling of surface fire behaviour in maritime pine stands." International Journal of Wildland Fire 18, no. 6 (2009): 698. http://dx.doi.org/10.1071/wf08023.

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An experimental burning program took place in maritime pine (Pinus pinaster Ait.) stands in Portugal to increase the understanding of surface fire behaviour under mild weather. The spread rate and flame geometry of the forward and backward sections of a line-ignited fire front were measured in 94 plots 10–15 m wide. Measured head fire rate of spread, flame length and Byram’s fire intensity varied respectively in the intervals of 0.3–13.9 m min–1, 0.1–4.2 m and 30–3527 kW m–1. Fire behaviour was modelled through an empirical approach. Rate of forward fire spread was described as a function of surface wind speed, terrain slope, moisture content of fine dead surface fuel, and fuel height, while back fire spread rate was correlated with fuel moisture content and cover of understorey vegetation. Flame dimensions were related to Byram’s fire intensity but relationships with rate of spread and fine dead surface fuel load and moisture are preferred, particularly for the head fire. The equations are expected to be more reliable when wind speed and slope are less than 8 km h–1 and 15°, and when fuel moisture content is higher than 12%. The results offer a quantitative basis for prescribed fire management.

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Johnston, J. M., M. J. Wooster, and T. J. Lynham. "Experimental confirmation of the MWIR and LWIR grey body assumption for vegetation fire flame emissivity." International Journal of Wildland Fire 23, no. 4 (2014): 463. http://dx.doi.org/10.1071/wf12197.

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The temperature and emissivity of forest fire flames play a key role in understanding fire behaviour, modelling fire spread and calculating fire parameters by means of active fire thermal remote sensing. Essential to many of these is the often-made assumption that vegetation fire flames behave as grey bodies in the infrared (IR). Although the emissivity of flames and its relationship to flame depth has been measured experimentally using thermal imagers working in the long-wave IR (LWIR, 8–12µm), no published study has yet demonstrated relationships in the important mid-wave IR (MWIR, 3–5µm) spectral region, nor conclusively demonstrated that assumptions about grey body behaviour across these two important IR atmospheric windows fit well with reality. Our study explores these issues using measurements of boreal forest fuels burned with flame depths ranging from 0.2 to 4.2 m. Observations of two stable black body sources made through the differing flame depths were used to explore flame spectral emissivities and their relationship to flame depth. We found essentially the same relationship between flame emissivity and flame depth for both spectral regions, (extinction coefficient K=0.7 m–1), confirming that the grey body assumption for forest fire flames in the MWIR and LWIR atmospheric windows appears valid for the fire conditions encountered here.

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Mendes-Lopes, José M. C., João M. P. Ventura, and José M. P. Amaral. "Flame characteristics, temperature - time curves, and rate of spread in fires propagating in a bed of Pinus pinaster needles." International Journal of Wildland Fire 12, no. 1 (2003): 67. http://dx.doi.org/10.1071/wf02063.

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An extensive set of experiments was carried out in order to collect data to validate fire propagation models being developed in the context of an European research project. The experiments were performed in a dedicated burning tray (2.0 m × 0.70 m working section), where wind velocity, fuel moisture content and slope were varied to study fire propagation in beds of Pinus pinaster needles. All the runs were videotaped and, from the recordings, information on flame geometry (i.e. flame height, flame length and flame angle) and rate of spread was obtained. Temperature measurements were also carried out by a small tower of six thermocouples at different heights above the fuel bed. Results show that headfire rate of spread increases steeply with wind speed for wind-driven fires but does not depend on wind speed for backing fire spread rates. Rate of spread increases slightly with slope for up-hill propagation, and is not slope dependent for down-hill cases. Rate of spread decreases when fuel moisture content increases. Flame angle and flame height are also dependent on wind velocity, slope, and fuel moisture content. The importance of temperature for fire propagation is discussed, emphasizing the role of radiation heat transfer in the process. Correlations between temperature and other indicators of fire behaviour (namely the rate of spread) are presented. Results are discussed and compared. The results obtained provide a good database for the assessment of fire propagation models.

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Zhao, Kun, Xiao Dong Zhou, Fei Peng, Xiao Yu Ju, and Li Zhong Yang. "Experimental Study on Flame Spread over Inclined PMMA and PE Slabs." Key Engineering Materials 775 (August 2018): 390–94. http://dx.doi.org/10.4028/www.scientific.net/kem.775.390.

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The effects of orientation on flame spread over the upper surface of PMMA and PE slabs were studied through a series of experiments. For fuel inclined angles smaller than 75° in this study, flame spread would arrive a steady-state stage finally. The flame spread rate and the angle of the fire plume near pyrolysis front in the steady-state stage were measured to investigate the differences between flame spread over melting and non-melting solids. Compared to the flame spread over polymethyl methacrylate (PMMA), the melting behaviors of high density polyethylene (PE) significantly decrease the flame spread rate, which is mainly attributed to the decreased size of fire plume and reduced interactions between fire plume and solid surface. The angles of the fire plume in the steady-state stage under different fuel inclined angles were measured to better understand the melting effects on flame spread over the inclined solid surface.

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Anderson, W. R., E. A. Catchpole, and B. W. Butler. "Convective heat transfer in fire spread through fine fuel beds." International Journal of Wildland Fire 19, no. 3 (2010): 284. http://dx.doi.org/10.1071/wf09021.

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An extensive set of wind-tunnel fires was burned to investigate convective heat transfer ahead of a steadily progressing fire front moving across a porous fuel bed. The effects of fuel and environmental variables on the gas temperature profile and the ‘surface wind speed’ (gas velocity at the fuel bed surface) are reported. In non-zero winds, the temperature of the air near the fuel bed surface decays exponentially with distance from the fire front. In zero winds, the temperature decreases rapidly within a very short distance of the flame front, then decays slowly thereafter. The maximum air temperature decreases as the free stream wind speed, packing ratio and fuel moisture content increase. The characteristic distance of the exponential decay increases strongly with the free stream wind speed and decreases with the packing ratio and surface area-to-volume ratio of the fuel. The surface wind speed depends strongly on the free stream wind speed, and to a lesser extent on packing ratio, fuel bed depth and fuel moisture content. There are three general regimes for the surface flow: (1) a constant velocity flow of approximately half the free stream flow, far from the flame front; (2) an intermediate zone of minimum flow characterised by low or reversed flow; and (3) a region near the flame front where the velocity rises rapidly almost to the free stream velocity. The boundaries between the three regions move further from the flame front with increasing wind speed, in a way which is only slightly affected by fuel geometry.

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Zhou, Ru, Zhihao Chen, Yinke Fan, Zhengjiang Yu, Jianan Qian, and Juncheng Jiang. "Fire Spread Characteristics of Metal-Polyethylene Sandwich Panels." Buildings 11, no. 9 (September 5, 2021): 396. http://dx.doi.org/10.3390/buildings11090396.

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An experimental study was conducted to determine the characteristics of the flame spread and droplets of metal-polyethylene (PE) sandwich panels during combustion. The mass-loss rate, average flame height, temperature, and fire spread rate were investigated. The results showed that the fire spread rate, mass change of the droplets, average flame height, and temperature increased with an increase in the sample length, except for the mass loss rate of the 40 cm-long sample. The time interval between the droplets decreased, and the flame pulsation frequency increased. The relationship between the flame height and sample length was determined. During the combustion process, bending deformation and top flame phenomena occurred due to the shrinkage of the PE, which increased the fire risk. The distance between the outer surface of the expanded metal aluminum layer and the insulation panel increased with an increase in the panel length. A schematic diagram of the fire spread of the metal sandwich panel was established based on the observations and theoretical analysis. The mechanism and combustion behavior of the metal sandwich panels were determined to provide references for the construction of metal sandwich panels of exterior walls.

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Weise, David R., Eunmo Koo, Xiangyang Zhou, Shankar Mahalingam, Frédéric Morandini, and Jacques-Henri Balbi. "Fire spread in chaparral – a comparison of laboratory data and model predictions in burning live fuels." International Journal of Wildland Fire 25, no. 9 (2016): 980. http://dx.doi.org/10.1071/wf15177.

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Fire behaviour data from 240 laboratory fires in high-density live chaparral fuel beds were compared with model predictions. Logistic regression was used to develop a model to predict fire spread success in the fuel beds and linear regression was used to predict rate of spread. Predictions from the Rothermel equation and three proposed changes as well as two physically based models were compared with observed spread rates of spread. Flame length–fireline intensity relationships were compared with flame length data. Wind was the most important variable related to spread success. Air temperature, live fuel moisture content, slope angle and fuel bed bulk density were significantly related to spread rate. A flame length–fireline intensity model for Galician shrub fuels was similar to the chaparral data. The Rothermel model failed to predict fire spread in nearly all of the fires that spread using default values. Increasing the moisture of extinction marginally improved its performance. Modifications proposed by Cohen, Wilson and Catchpole also improved predictions. The models successfully predicted fire spread 49 to 69% of the time. Only the physical model predictions fell within a factor of two of actual rates. Mean bias of most models was close to zero. Physically based models generally performed better than empirical models and are recommended for further study.

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Rodríguez y Silva, Francisco, Mercedes Guijarro, Javier Madrigal, Enrique Jiménez, Juan R. Molina, Carmen Hernando, Ricardo Vélez, and Jose A. Vega. "Assessment of crown fire initiation and spread models in Mediterranean conifer forests by using data from field and laboratory experiments." Forest Systems 26, no. 2 (July 24, 2017): e02S. http://dx.doi.org/10.5424/fs/2017262-10652.

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Aims of study: To conduct the first full-scale crown fire experiment carried out in a Mediterranean conifer stand in Spain; to use different data sources to assess crown fire initiation and spread models, and to evaluate the role of convection in crown fire initiation.Area of study: The Sierra Morena mountains (Coordinates ETRS89 30N: X: 284793-285038; Y: 4218650-4218766), southern Spain, and the outdoor facilities of the Lourizán Forest Research Centre, northwestern Spain.Material and methods: The full-scale crown fire experiment was conducted in a young Pinus pinea stand. Field data were compared with data predicted using the most used crown fire spread models. A small-scale experiment was developed with Pinus pinaster trees to evaluate the role of convection in crown fire initiation. Mass loss calorimeter tests were conducted with P. pinea needles to estimate residence time of the flame, which was used to validate the crown fire spread model.Main results: The commonly used crown fire models underestimated the crown fire spread rate observed in the full-scale experiment, but the proposed new integrated approach yielded better fits. Without wind-forced convection, tree crowns did not ignite until flames from an intense surface fire contacted tree foliage. Bench-scale tests based on radiation heat flux therefore offer a limited insight to full-scale phenomena.Research highlights: Existing crown fire behaviour models may underestimate the rate of spread of crown fires in many Mediterranean ecosystems. New bench-scale methods based on flame buoyancy and more crown field experiments allowing detailed measurements of fire behaviour are needed.

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Dupuy, J. L., J. Maréchal, D. Portier, and J. C. Valette. "The effects of slope and fuel bed width on laboratory fire behaviour." International Journal of Wildland Fire 20, no. 2 (2011): 272. http://dx.doi.org/10.1071/wf09075.

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A set of 109 laboratory fires in Pinus halepensis fuel beds (1 kg m–2) was used to test the effects of slope (0°, 10°, 20°, 30°) and fuel bed width (1, 2, 3 m) on fire behaviour variables such as rate of spread, fuel consumption, flame residence time, temperatures and flame geometry. The qualitative behaviour of the fires is also reported. The 20° and 30° upslope fires are pointed in shape and fire whirls moving along the fire flanks in the direction of the fire head are systematically observed in 30° upslope fires. Flame residence time increases with increasing slope angle, and both slope angle and fuel bed width affect rate of spread. The slope effects observed in 10° and 20° slope angles and in the narrowest fuel beds (1 and 2 m) are similar to those predicted by operational models. However, the observed slope effect at the 30° slope angle is underestimated by these models, in particular in 3 m-wide fuel beds. Flame temperatures correlate closely with dimensionless height and flame lengths correlate closely with fire line intensity. Mechanisms that could explain the different effects observed are suggested and discussed.

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Li, Xia, and Xuan Jun Wang. "Research on the Flame Spread Characteristics of Safety Diesel Microemulsion." Advanced Materials Research 512-515 (May 2012): 2515–18. http://dx.doi.org/10.4028/www.scientific.net/amr.512-515.2515.

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The paper studies the flame spread characteristics of the diesel with safety performance by schlieren technology. The flame of fire spreading of the diesel includes flash fire flame which is blue and main flame which is orange. The main flame spread forward in the reciprocating and pulsatile pattern, while the flash fire flame spread with the level discontinuous pulsatile pattern. The water content in the diesel has notable restriction effect on the speed of the flame spreading, which is decreased with the increasing of the water content. But the micro-emulsified diesel can’t effectively restrain the spread speed when water content is below 3%. The microemulsified diesel whose water content being in the range of 3%~12% could be used in engine.

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Morandini, Frédéric, and Xavier Silvani. "Experimental investigation of the physical mechanisms governing the spread of wildfires." International Journal of Wildland Fire 19, no. 5 (2010): 570. http://dx.doi.org/10.1071/wf08113.

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One of the objectives of the present study is to gain a deeper understanding of the heat transfer mechanisms that control the spread of wildfires. Five experimental fires were conducted in the field across plots of living vegetation. This study focussed on characterising heat transfer ahead of the flame front. The temperature and heat flux were measured at the top of the vegetation as the fire spread. The results showed the existence of two different fire spread regimes that were either dominated by radiation or governed by mixed radiant–convective heat transfer. For plume‐dominated fires, the flow strongly responds to the great buoyancy forces generated by the fire; this guides the fire plume upward. For wind‐driven fires, the flow is governed by inertial forces due to the wind, and the fire plume is greatly tilted towards unburned vegetation. The correlations of the temperature (ahead of the flame front) and wind velocity fluctuations change according to the fire regime. The longitudinal distributions of the radiant heat flux ahead of the fire front are also discussed. The data showed that neither the convective Froude number nor the Nelson convection number – used in the literature to predict fire spread regimes – reflect the observed behaviour of wind‐driven fires.

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Lönnermark, Anders, and Haukur Ingason. "Fire Spread and Flame Length in Large-Scale Tunnel Fires." Fire Technology 42, no. 4 (April 24, 2006): 283–302. http://dx.doi.org/10.1007/s10694-006-7508-7.

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Cohen, Jack D. "Relating flame radiation to home ignition using modeling and experimental crown fires." Canadian Journal of Forest Research 34, no. 8 (August 1, 2004): 1616–26. http://dx.doi.org/10.1139/x04-049.

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Wildlandurban fire destruction depends on homes igniting and thus requires an examination of the ignition requirements. A physicaltheoretical model, based on severe case conditions and ideal heat transfer characteristics, estimated wood wall ignition occurrence from flame radiation heating and piloted ignition requirements. Crown fire experiments provided an opportunity for assessing model reliability. The crown fire experiments were specifically instrumented with wood wall sections and heat flux sensors to investigate direct flame heating leading to home ignition during wildland fires. The experimental results indicated that the flame radiation model overestimated the structure-to-flame distance that would result in wood wall ignition. Wall sections that ignited during the experimental crown fires did not sustain flaming after crown fire burnout. The experiments also revealed that the forest canopy attenuated the flame radiation as the crown fire spread within the forest plot. Ignition modeling and the associated crown fire experiments described the flame-to-structure distance scale associated with flame heating related to wall ignition.

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Nečas, Aleš, Jozef Martinka, Igor Wachter, Tomáš Štefko, Martina Hladová, Denis Benko, Karol Balog, and Libor Ševčík. "Impact of Selected Electrical Cables Slope on Flame Out Time and Flame Spread." Research Papers Faculty of Materials Science and Technology Slovak University of Technology 27, no. 44 (June 1, 2019): 41–47. http://dx.doi.org/10.2478/rput-2019-0004.

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Abstract The aim of the research described in this paper was to study the impact of the electrical cables slope on the flame out time and the flame spread rate. Measured cables were thermally loaded by methanol flame (diameter of the container was 106 mm) at seven different slopes with respect to the horizontal plane (the slopes were 0° – horizontal orientation, 15°, 30°, 45°, 60°, 75° and 90° - vertical orientation). The first tested electrical cable was a copper three-core power one resistant to the flame spread with circuit integrity of the cable system during 30 minutes under fire (cross-section of each core was 1.5 mm2). The second tested electrical cable was a copper two-core signal one resistant to the flame spread with circuit integrity of the cable system during 30 minutes under fire (cross-section of each core was 0.5 mm2). The first electrical cable did not show reaction to fire class. The reaction to fire class of the second tested cable was B2ca, s1, d1, a1. The obtained results proved that slope had virtually no impact on the flame out time and the flame spread over the tested cable surface (tested cables of all slopes stopped burning after 1 to 5 seconds after methanol flame burned out). Likewise, the flame spread was only negligibly beyond the border of flame action for each cable slope.

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Hasemi, Y., Masashi Yoshida, Y. Yokobayashi, and Takao Wakamatsu. "Flame Heat Transfer And Concurrent Flame Spread In A Ceiling Fire." Fire Safety Science 5 (1997): 379–90. http://dx.doi.org/10.3801/iafss.fss.5-379.

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An, Wei Guang, Lin Jiang, Jin Hua Sun, and K. M. Liew. "Effect of Sample Width on Downward Flame Spread over Typical Energy Conservation Material at a High Elevation Area." Applied Mechanics and Materials 664 (October 2014): 199–203. http://dx.doi.org/10.4028/www.scientific.net/amm.664.199.

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An experimental study on downward flame spread over extruded polystyrene (XPS) foam at a high elevation is presented. The flame shape, flame height, mass loss rate and flame spread rate were measured. The influences of width and high altitude were investigated. The flame fronts are approximately horizontal. Both the intensity of flame pulsation and the average flame height increase with the rise of sample width. The flame spread rate first drops and then rises with an increase in width. The average flame height, mass loss rate and flame spread rate at the higher elevation is smaller than that at a low elevation, which demonstrates that the XPS fire risk at the higher elevation area is lower. The experimental results agree well with the theoretical analysis. This work is vital to the fire safety design of building energy conservation system.

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Markus, E. S., A. Yu Snegirev, E. A. Kuznetsov, L. T. Tanklevskiy, and A. V. Arakcheev. "Simulation of flame spread over discrete fire load." Пожаровзрывобезопасность 28, no. 4 (August 2019): 29–41. http://dx.doi.org/10.18322/pvb.2019.28.04.29-41.

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Thomsen, Maria, Daniel C. Murphy, Carlos Fernandez-pello, David L. Urban, and Gary A. Ruff. "Flame spread limits (LOC) of fire resistant fabrics." Fire Safety Journal 91 (July 2017): 259–65. http://dx.doi.org/10.1016/j.firesaf.2017.03.072.

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Liu, Naian, Jinmo Wu, Haixiang Chen, Xiaodong Xie, Linhe Zhang, Bin Yao, Jiping Zhu, and Yanlong Shan. "Effect of slope on spread of a linear flame front over a pine needle fuel bed: experiments and modelling." International Journal of Wildland Fire 23, no. 8 (2014): 1087. http://dx.doi.org/10.1071/wf12189.

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This paper experimentally evaluates the effect of slope on spread of a linear flame front over a pine needle fuel bed in still air. The slope angle of the fuel bed varied from 0 to 32°. The fuel mass consumption in flaming fire spread, temperature over the fuel bed, velocities of the flow around the flame front and heat fluxes (total and radiant) near the end of the fuel bed were measured. The mass loss rate and rate of fire spread both increased with increasing slope, whereas the fuel consumption efficiency varied in the opposite way. It was shown that a weak reverse inflow and an upslope wind (induced by the flame itself) exist respectively ahead of and behind the flame front, and their significant difference in velocity (causing a pressure difference) plays an essential role in the forward tilting of the flame front. This mechanism promotes burning, especially on higher slopes. Natural convective cooling has a remarkable effect on the fuel pre-heating in the spread of linear flame fronts under slope conditions. A fire spread model for a linear flame front was developed to consider the natural convective cooling and the fuel consumption efficiency. The model agrees well with the experimental data on fire spread rate. Its reliability, especially for higher slopes, was verified by comparison with other models.

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de Groot, W. J., P. M. Bothwell, S. W. Taylor, B. M. Wotton, B. J. Stocks, and M. E. Alexander. "Jack pine regeneration and crown fires." Canadian Journal of Forest Research 34, no. 8 (August 1, 2004): 1634–41. http://dx.doi.org/10.1139/x04-073.

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The effect of crown fires on Pinus banksiana Lamb. regeneration was studied in separate forest- and cone-burning experiments. Nine plots (0.562.25 ha) of jack pine trees near Fort Providence, Northwest Territories, were burned using crown fires to determine the effects of fire intensity, rate of fire spread, depth of burn, and postfire duff depth on seed viability and regeneration. Fire intensities were 36 902 93 476 kW/m, and fire spread rates were 2470 m/min. Depths of burn were low (2.03.6 cm), and postfire duff depths averaged 2.05.5 cm. Postfire seed rain was highly variable (64634 seeds/m2), but seed viability was near 67% on all plots. Jack pine regeneration was also highly variable (779 seedlings/m2). In the cone-burning experiment, the germination rate increased from 41% (unheated cones) to 64% after 10 s of burning but decreased sharply after 30 s. Flame temperature did not significantly affect viability. Cone-burning results suggest that the postfire seed rain originated from the upper canopy, where flame duration was 515 s, and seed in the lower canopy was consumed by fire. Seed rain and regeneration were primarily influenced by understory fine fuel consumption (and therefore, fire intensity), tree height, and live crown base height.

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Zhou, Ning, Chun Ling Zhu, Yu Ting Bao, Guang Qi Ji, and Xuan Qing Qian. "Simulated Fire Testing of a Real Building with EPS Exterior Thermal Insulation Composite Systems (ETICS) Including Rock Wool Fire Barrier." Applied Mechanics and Materials 368-370 (August 2013): 868–72. http://dx.doi.org/10.4028/www.scientific.net/amm.368-370.868.

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In this paper, a three stories villa was build and furniture was arranged according to the actual usage condition. The scene that building caught fire and flames escaped from the window and spread upward along the facade cladding system was simulated to verify the actual effect of fire barrier. The results showed that the first fire barrier obviously prevented flame dispersing and can raise ETICS fire safe ability.

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Ivchenko, Ol'ga, and Kirill Pankin. "FIRE PROTECTION TEST OF ALUMINUM AND BORON COMPOUNDS FOR STRUGGLE AGAINST GROUND FIRES." Forestry Engineering Journal 10, no. 2 (July 6, 2020): 47–59. http://dx.doi.org/10.34220/issn.2222-7962/2020.2/5.

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The fight against ground forest fires includes three measures: (1) preventing the occurrence, (2) limiting the spread, and finally, if the first two did not help, (3) extinguishing the edge of the fire. It is impossible to completely eliminate the factors contributing to the onset and development of fires in these territories. Therefore, measures to prevent the free spread of fire will be the most effective ones. A method is proposed to prevent and limit the spread of ground fire by creating fire-retardant strips. These are areas covered with grass and plant debris, treated (by spraying) with aqueous solutions of aluminum hydrogels. The efficiency of the flame retardant properties of such strips has been studied during field experiments. It has shown that obvious signs of fire-retardant effect of aluminum hydrogel begin to appear at a concentration of 7 g/l, with a flow rate of 1 liter of solution per 1 m2 of the treated area. In this case, ground fire loses its stability and its speed decreases 2-3 times. The treatment of the plots with hydrogel solutions with a concentration of 14 g/l or more completely prevented the spread of the flame over the grass cover. In addition, attempts to force the site to burn (28 g/l) were unsuccessful. A water-soluble compound of boron - sodium tetraborate - with concentrations of 3.5-28 g/l does not have sufficient fire retardant action to stop the spread of ground fire.

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Knapp, Eric E., J. Morgan Varner, Matt D. Busse, Carl N. Skinner, and Carol J. Shestak. "Behaviour and effects of prescribed fire in masticated fuelbeds." International Journal of Wildland Fire 20, no. 8 (2011): 932. http://dx.doi.org/10.1071/wf10110.

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Mechanical mastication converts shrub and small tree fuels into surface fuels, and this method is being widely used as a treatment to reduce fire hazard. The compactness of these fuelbeds is thought to moderate fire behaviour, but whether standard fuel models can accurately predict fire behaviour and effects is poorly understood. Prescribed burns were conducted in young ponderosa pine (Pinus ponderosa Laws.) forests at two sites in northern California where the midstorey layer dominated by shrubs had been masticated. Surface fuels were raked from the base of a subset of trees before burning. Rate of spread and flame length were estimated for both backing and heading fires, soil heating measured with thermocouples and tree fire injury recorded. Standard fuel models often over-predicted rate of spread or under-predicted flame length. Custom models generally provided a better balance between the slow rates of spread and moderate flame lengths observed in prescribed burns. Post-fire tree mortality was most strongly associated with crown scorch and tree size; raking fuels from the base of trees did not improve survival. Under severe fire weather conditions, fire behaviour and effect models as well as observations from wildfires suggest that mastication may be more effective for moderating fire behaviour than reducing residual tree mortality. Treating masticated fuels with prescribed burns could potentially improve the resilience of stands to wildfire.

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Nelson Jr., Ralph M., and Carl W. Adkins. "A dimensionless correlation for the spread of wind-driven fires." Canadian Journal of Forest Research 18, no. 4 (April 1, 1988): 391–97. http://dx.doi.org/10.1139/x88-058.

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Data for the behavior of 59 experimental wind-driven fires were extracted from the literature for use in determining a correlation among several variables known to influence the rate of forest fire spread. Also included in the correlation were unpublished data from six field fires. This information consisted of behavior measurements on small-scale burns of artificial fuels in the laboratory and measurements on field fires in diverse fuels such as grass and logging slash. Fire intensities ranged from about 40 to 4600 kW/m. Dimensional analysis was used to derive three variables governing the fire spread process. These variables, rearranged into a dimensionless rate of spread and a dimensionless wind speed, are strongly correlated and lead to a simple expression for fire spread rate in terms of fuel consumption, ambient wind speed, and flame residence time.

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Wang, Lu, Yi Xing Bi, Wei Wu, and Da Jun Xu. "Large-Scale Experimental Investigation of the Fire Characteristics Parameters of Methanol in Coal Chemical Industry." Applied Mechanics and Materials 713-715 (January 2015): 2745–49. http://dx.doi.org/10.4028/www.scientific.net/amm.713-715.2745.

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A steel channel with the size of 30×2×1.2 m was made to simulate the full surface fire of 50000 m3methanol tank in coal-to-olefins industry. Some fire characteristic parameters of methanol were investigated, including flame spread rate, flame height, temperature distribution and radiation heat flux distribution. It is found that the flame spread rate of methanol is 1.98 m/s and the flame height could reach to 3.2 m. The temperature of methanol flame is first up and then down with the increase of height, while the highest temperature is 768oC. It is also found that the radiation heat flux of methanol flame is in the changes between 4.4 kW/m2and 12.2 kW/m2. The feature of methanol fire is different from the normal oil fire, which is worth for us to pay more attention.

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YAN, Weigang, Lin JIANG, Weiguang AN, Yang ZHOU, and Jinhua SUN. "Large scale experimental study on the fire hazard of buildings’ U-shape façade wall geometry." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 23, no. 4 (April 21, 2017): 455–63. http://dx.doi.org/10.3846/13923730.2016.1210671.

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Buildings have U-shape façade designs for certain purposes such as lighting. However, such designs may lead to a higher fire hazard. In this paper, large scale experiments of upward flame spread over XPS insulation material were conducted to investigate the fire hazard of building’s U-shape façade wall geometry. Comparison to previous laboratory scale experiments were also presented. Theoretical analysis was performed to reveal the mechanism of the U-shape geometry’s influences. It is found that such geometry design would increase the fire hazard of buildings: flame spread rate and flame height increased with U-shape’s geometrical factor. The results agreed with theoretical analysis. It is expected that the buildings’ U-shape façade wall geometry would greatly benefit flame spread for full scale applications and increase the fire hazard. Thus engineers should be careful with such façade wall designs, especially for residential building designs.

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YOKOBAYASHI, Yutaka, Yuji HASEMI, Masashi YOSHIDA, and Takao WAKAMATSU. "FLAME HEAT TRANSFER CORRELATIONS AND CONCURRENT FLAME SPREAD IN A CEILING FIRE." Journal of Architecture and Planning (Transactions of AIJ) 64, no. 519 (1999): 1–7. http://dx.doi.org/10.3130/aija.64.1_5.

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Xie, Qiyuan, Tai Gong, and Xinyan Huang. "Fire Zone Diagram of Flame-retardant Cables: Ignition and Upward Flame Spread." Fire Technology 57, no. 5 (May 22, 2021): 2643–59. http://dx.doi.org/10.1007/s10694-021-01133-x.

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Pickford, S., M. Suharti, and A. Wibowo. "A Note on Fuelbeds and Fire Behavior in Alang-Alang (Imperata Cylindrica)." International Journal of Wildland Fire 2, no. 1 (1992): 41. http://dx.doi.org/10.1071/wf9920041.

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Fire behavior on a 2 ha fire, inferred from physical evidence observed one week after the fire, was compared with fire behavior estimates obtained using the BEHAVE fire behavior prediction system and fuel measurements in Imperata cylindrica (Alang-alang) made in the same area. This fire probably burned under light winds (3-5 km), high relative humidity, and spread slowly with moderate flame lengths (approximately 100 m hr-1 spread rate, 0.5 - 0.7 m flame lengths). Although appar- ently killed by lethal crown and bole scorch, the young Acacia mangium overstory through which the fire burned resprouted vigorously and apparently survived.

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Tewarson, Archibald, and Domenic P. Macaione. "Polymers and Composites- An Examination of Fire Spread and Generation of Heat and Fire Products." Journal of Fire Sciences 11, no. 5 (September 1993): 421–41. http://dx.doi.org/10.1177/073490419301100504.

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Fiber reinforced composite (FRC) materials are used extensively because of their favorable physico-chemical properties and high strength- to-weight ratio. The use of composites in Army vehicles as a means of decreas ing weight and enhancing survivability, without reducing personnel safety, has been under study for some time. Although FRC materials are very attractive in terms of their physico-chemical properties, concern for possible fire hazard is understandable as organic polymers are one of the major constituents of the materials. A joint study thus was undertaken by the U.S. Army Materials Tech nology Laboratory (MTL) and the Factory Mutual Research Corporation (FMRC) to quantify flammability behavior of selected composite materials for the assessment of fire hazard. In the study, eight FRC materials, identified as MTL #1 to #8, were used. The FRC materials were 3 to 45 mm in thickness. The flammability behavior was examined by using the FMRC Flammability Apparatus (50 kW-Scale) and Ox ygen Index (OI) apparatus, Thermogravimetric Analysis (TGA) instrument, NBS smoke chamber (ASTM E 662), and Gas Chromatograph-Mass Spec trometer (GC-MS) instrument at MTL. This article presents results for ignition, flame spread, heat release rate, gen eration rates of products, light obscuration by smoke and flame extinction by Halon. In comparison to ordinary combustibles, such as cellulosics and most non fire retarded plastics, the eight FRC materials have higher resistance to ig nition (as indicated by the Thermal Response Parameter, TRP) and flame spread (as indicated by higher values of the Fire Propagation Index, FPI). The FPI values for the FRC materials, examined in this study, ranged from 3 to 13, indicating that for Group 1 FRC materials (FPI < 10), self-sustained flame spread beyond the ignition zone would be difficult, whereas for other Group 2 materials ( FPI ≥ 10), flame spread beyond the ignition zone would be ex pected, although at a slower rate. For Group 2 materials fire protection is re quired, which could be provided by techniques such as surface coating, surface lamination using highly fire resistant FRC materials, and others. Generation of heat, smoke, toxic and corrosive products is closely related to FPI. Within the FRC materials, examined in this study, differences were found between the generation rates of heat, smoke, and other products. Results for flame extinction by Halon 1301 are also discussed. The flame ex tinction data are consistent with the design of the current suppression system for the crew compartment of Army combat vehicles. The study suggests that the FPI concept and associated parameters related to generation of heat, smoke, toxic, and corrosive products, is a useful concept for realistic flammability quantification and screening of FRC materials and for use in the hazard assessment. This, however, needs to be validated by perform ing large-scale fire tests.

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Cruz, Miguel G., Andrew L. Sullivan, James S. Gould, Richard J. Hurley, and Matt P. Plucinski. "Got to burn to learn: the effect of fuel load on grassland fire behaviour and its management implications." International Journal of Wildland Fire 27, no. 11 (2018): 727. http://dx.doi.org/10.1071/wf18082.

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The effect of grass fuel load on fire behaviour and fire danger has been a contentious issue for some time in Australia. Existing operational models have placed different emphases on the effect of fuel load on model outputs, which has created uncertainty in the operational assessment of fire potential and has led to end-user and public distrust of model outcomes. A field-based experimental burning program was conducted to quantify the effect of fuel load on headfire rate of spread and other fire behaviour characteristics in grasslands. A total of 58 experimental fires conducted at six sites across eastern Australia were analysed. We found an inverse relationship between fuel load and the rate of spread in grasslands, which is contrary to current, untested, modelling assumptions. This result is valid for grasslands where fuel load is not a limiting factor for fire propagation. We discuss the reasons for this effect and model it to produce a fuel load effect function that can be applied to operational grassfire spread models used in Australia. We also analyse the effect of fuel load on flame characteristics and develop a model for flame height as a function of rate of fire spread and fuel load.

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Osorio, Andres F., Carlos Fernandez-Pello, David L. Urban, and Gary A. Ruff. "Limiting conditions for flame spread in fire resistant fabrics." Proceedings of the Combustion Institute 34, no. 2 (January 2013): 2691–97. http://dx.doi.org/10.1016/j.proci.2012.07.053.

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Khelloufi, K., Y. Baara, and N. Zekri. "Percolation and fire spread with power-law flame radiations." EPL (Europhysics Letters) 103, no. 2 (July 1, 2013): 26001. http://dx.doi.org/10.1209/0295-5075/103/26001.

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Morvan, Dominique. "A numerical study of flame geometry and potential for crown fire initiation for a wildfire propagating through shrub fuel." International Journal of Wildland Fire 16, no. 5 (2007): 511. http://dx.doi.org/10.1071/wf06010.

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The efficiency of fuel breaks installed in wildland–urban interfaces to reduce fire hazard depends strongly on the conditions of spread (rate of spread, flame height) of a surface fire through the shrub on the ground and also on the possibility of a transition for this fire from the understorey vegetation to the canopy. The aim of the present paper was to study (using numerical simulation with a physics-based model) the behaviour of surface fires propagating through Mediterranean shrub and to evaluate, from the characteristic dimensions of the flame, the onset of transition from a surface fire to a crown fire. The geometry of the flame was defined from the energy loss in the gas resulting from the radiation emission of soot particles, the flame contour was reconstructed from a threshold level fixed at 60 kW m–3. The numerical results were compared with experimental correlations of the geometry of the flame obtained for static and spreading fires. Extensive calculations were performed through a shrubland (Quercus coccifera and Brachypodium ramosum) for various fuel depths Hfuel ranging from 0.25 to 1.5 m and for wind speeds UH ranging from 1 to 10 m s–1. Then this study was extended to situations including a supplementary fuel layer representing the canopy of small trees (Pinus halepensis). The numerical results were analysed, introducing a dimensionless physical parameter, the Froude number, defined as the ratio between the inertial force due to the wind flow and the buoyancy. The results obtained with an upper fuel layer highlighted the role played by radiation heat transfer for the transition of surface fire to the crown. Some calculations were also carried out to study how a reduction of surface fuel on the ground can affect the vertical transition of the fire.

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Marsden-Smedley, JB, and WR Catchpole. "Fire Behaviour Modelling in Tasmanian Buttongrass Moorlands .II. Fire Behaviour." International Journal of Wildland Fire 5, no. 4 (1995): 215. http://dx.doi.org/10.1071/wf9950215.

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An experimental burning program was carried out in Tasmanian buttongrass moorlands to develop fire behaviour prediction models for improving fire management. A range of previously developed prediction models were examined, but none provided adequate fire behaviour predictions. Empirical models were then developed to predict rate of fire spread and flame height in flat terrain, using the variables site age, dead fuel moisture content and surface wind speed. The models should provide good predictions for low to moderate intensity fires and adequate predictions for high intensity wildfires.

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Finney, Mark A., and Sara S. McAllister. "A Review of Fire Interactions and Mass Fires." Journal of Combustion 2011 (2011): 1–14. http://dx.doi.org/10.1155/2011/548328.

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The character of a wildland fire can change dramatically in the presence of another nearby fire. Understanding and predicting the changes in behavior due to fire-fire interactions cannot only be life-saving to those on the ground, but also be used to better control a prescribed fire to meet objectives. In discontinuous fuel types, such interactions may elicit fire spread where none otherwise existed. Fire-fire interactions occur naturally when spot fires start ahead of the main fire and when separate fire events converge in one location. Interactions can be created intentionally during prescribed fires by using spatial ignition patterns. Mass fires are among the most extreme examples of interactive behavior. This paper presents a review of the detailed effects of fire-fire interaction in terms of merging or coalescence criteria, burning rates, flame dimensions, flame temperature, indraft velocity, pulsation, and convection column dynamics. Though relevant in many situations, these changes in fire behavior have yet to be included in any operational-fire models or decision support systems.

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Taylor, S. W., B. M. Wotton, M. E. Alexander, and G. N. Dalrymple. "Variation in wind and crown fire behaviour in a northern jack pine black spruce forest." Canadian Journal of Forest Research 34, no. 8 (August 1, 2004): 1561–76. http://dx.doi.org/10.1139/x04-116.

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Fire spread and flame temperature were examined in a series of nine experimental crown fires conducted in the Northwest Territories, Canada. Average rates of spread were 17.866.8 m·min1 (0.31.1 m·s1) over burning periods from about 1.510 min across 75 m × 75 m to 150 m × 150 m plots. Detailed maps of fire front progression revealed areas with higher rates of spread in the order of tens of metres in horizontal dimension and tens of seconds in duration in several of the fires, which is consistent with the influence of coherent wind gusts. Comparison of open and in-stand wind speed before and after burning suggests that defoliation in the canopy layer during burning would result in the flaming zone having greater exposure to the ambient wind. Estimates of flame front residence from video observations at the surface averaged 34 s; estimates from temperature measurements decreased significantly with height from 74 s at the surface to 31 s below the canopy.

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Chow, Wan, and Wai Leung. "Recommendation of tests for assessing flame spread of materials in Hong Kong." Thermal Science 11, no. 2 (2007): 53–66. http://dx.doi.org/10.2298/tsci0702053c.

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Performance-based design for passive building fire safety provisions is accepted by the authority in Hong Kong since 1998. This is also known as the "fire engineering approach", though the performance-based fire code is not yet available. To cope with the use of new building materials, appropriate flame spread tests on materials and components should be specified. After reviewing four standard tests in the literature, i.e. ASTM E1321-97a, BS476: Part 7: 1997, ASTM E84-99/NFPA 255, and ISO 9705: 1993(E), it appears that ISO 9705: 1993(E) is suitable for assessing the flame spread of materials. .

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Li, Jun Mei, Chen Chen Yin, Cheng Hu, Yan Feng Li, and Peng Xu. "Computational Study of Wind Effect on Window Flame Spread across the Exterior Wall of High-Rise Building." Applied Mechanics and Materials 438-439 (October 2013): 1898–902. http://dx.doi.org/10.4028/www.scientific.net/amm.438-439.1898.

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The fire in high-rise buildings is perhaps more dangerous than those occur in normal buildings because of the strong stack effect and wind effect on the fire. The wind effects on the wind flame spread across the exterior wall of the high rise building are studied in this paper by the numerical methods. The results show that high wind speed will change the wind flame spread direction and make the room inclined above the fire room more danger, especially the room at the same floor adjacent to the fire room. Special passive fire protection measures should be taken under these kinds of conditions.

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Tanskanen, Heidi, Anders Granström, Markku Larjavaara, and Pasi Puttonen. "Experimental fire behaviour in managed Pinus sylvestris and Picea abies stands of Finland." International Journal of Wildland Fire 16, no. 4 (2007): 414. http://dx.doi.org/10.1071/wf05087.

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Fire behaviour characteristics were studied in managed Pinus sylvestris L. and Picea abies L. Karst stands in a series of field burning experiments. Stand characteristics, surface fuel moisture content, mid-flame wind speed, rates of spread, flame heights, and torching were recorded. The Canadian Forest Fire Weather Index System (FWI System) and Finnish Fire Risk Index (FFI) were used to evaluate burning conditions and analyse the observed fire behaviour. Mid-flame wind speed was a good predictor (R2 = 0.96 for exponential curve) of the fire spread rates. Torching formed the strongest correlation with the height of the dead branch limit. An increase in predicted fire weather hazard from FWI 4 to FWI 20 (FWI = the FWI code of the FWI System) increased burn coverage remarkably in 15–45-year-old Pinus stands and to a lesser extent in Pinus and Picea clear-cuts, but did not affect 40–60-year-old Picea stands. The FFI was unable to predict burn coverage or any other fire behaviour characteristics.

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Journal articles on the topic 'Flame spread Fire'

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