Fire Spread Research Articles

Analysis and evaluation of the burning characteristics of six commonly used herbaceous species in Beijing.

Surface vegetations are one of the key factors affecting the spread of green space fires. To explore the combustibility of commonly used local surface layer herbaceous species in Beijing, and to provide a reference for the construction and management of urban green space, we comprehensively evaluated the combustibility of Carex giraldiana, Carex breviculis, Liriope spicata, Iris lactea, Iris tectorum, and Buffaloe dactyloides, with the entropy weight method and K-mean cluster analysis based on the principal component analysis method. We measured the combustion characteristics indicators (blade ignition point, combustion time and heat release rate), physical and chemical indicators (leaf moisture content and crude fat content), and biological characteristics indicators (blade thickness and unit load) during the key period of fire prevention. The results showed that blade thickness and ignition point got the highest weight and affected the overall combustibility most. Peak heat release rate and ignition time had the lowest weight and minimal impact on the overall combustibility. The combustibility of the six species followed an order of B. dactyloides > C. breviculmis > L. spicata > C. giraldiana > I. lactea > I. tectorum. Results of the clustering analysis showed that the combustion ability of B. dactyloides, C. breviculmis, and L. spicata were in class Ⅰ, with the strongest combustion ability; C. giraldiana was in class Ⅱ; I. lactea and I. tectorum were in class Ⅲ, with the lowest flammability. As widely used surface vegetations, critical attention should be paid on B. dactyloides, C. breviculmis and L. spicata for fire prevention in winter and spring.

Experimental study of fire exposed expanded polystyrene (EPS) insulation protected by selected coverings

Insulation products made of expanded polystyrene (EPS) are commonly utilized in buildings. However, Norwegian building regulations restrict the use of such combustible insulation due to an increased risk of fire spread and generation of smoke and toxic gases. Installation of fire protection coverings has been adopted as a mitigation strategy to address these safety risks. Notably, the current regulations lack pre-approved solutions describing what is considered an adequate protection of combustible insulation. The present study investigated the fire protection properties of selected coverings used to protect EPS insulation in inner walls. Eight comparative fire tests were conducted using an indicative fire resistance test furnace. The test specimens consisted of EPS blocks mounted on a wooden frame and covered with one or two layers of selected board coverings. The specimens were positioned vertically within the test furnace, and each fire test lasted for 10 or 15 min. Test results revealed that only two configurations consisting of either two layers of 12.5 mm gypsum boards or a combination of 12 mm oriented strand board (OSB) and 12.5 mm gypsum board showed no evidence of damage to the EPS substrate after a 15-min fire exposure. Consequently, the findings suggest that a total covering thickness of at least 24.5 mm, comprising two layers of boards, is necessary to prevent adverse effects on EPS insulation. Furthermore, fire tests conducted on coverings with introduced damages and defects showed that the affected area around the damages and defects were limited. For the standard EPS substrate, this area extended from 28 mm to 90 mm, while for the fire-retardant EPS substrate from 28 mm to 75 mm after a 10-min fire exposure. These results suggest that minor physical failures in the covering have limited impact on the fire safety of the system.

Real-time forest fire detection, monitoring, and alert system using Arduino

<div align="center"><span>Early fire detection is critical to protecting forests from wildfires and enabling rapid responses to minimize fire spread. Existing forest fire detection methods cannot quickly detect forest fires and evaluate the fire risk of these sensitive areas. Hence, this research aims to develop a real-time forest fire detection, monitoring, and alert system. The development of the</span><span> system started with assembling temperature and humidity sensors, a smoke sensor, an Arduino microcontroller, and a wireless fidelity module. Then, a fire monitoring and alert system was developed using Blynk. From the sensitivity flame sensor analysis with the fire, the flame sensor detected the <span>presence of fire up to 60 cm. The sensor also indicated high temperature (45 °C)</span> and low humidity (53.4%) at noon. Low temperature (29 ℃) and high humidity (88.4%) were identified in the morning. Moreover, the highest carbon dioxide (CO<sub>2</sub>) concentration of 1,800 ppm was recorded when the smoke from the fire was detected. The global positioning system module shows the accurate real-time location of the system displayed in the Blynk application. In conclusion, this system can detect and monitor early forest fires in real-time and can alert the authorities to protect forests from wildfires.</span></div>

Research on accurate fire detection & early warning model for lithium-ion battery packs

To improve the fire detection & early warning accuracy for lithium-ion battery packs and reduce false alarms and missing reports, the fire occurrence mechanism and cause factors of lithium-ion battery packs were analyzed, the calculation method of these characteristic parameters and basic judgment conditions of thermal runaway occurrence were explored, and then a thermal runaway-induced fire spread model of lithium-ion battery packs was established. Next, the scheme and model for accurate detection and early warning of lithium-ion battery pack fire was designed. Furthermore, an accurate fire detection & early warning model of “characteristic parameter sorting and screening + comprehensive conditional judgment + grading implementation” was proposed. Experimental results demonstrate that the accurate fire detection & early warning model for lithium-ion battery packs built in this study would be feasible.

Wildfire spreading prediction using multimodal data and deep neural network approach

Predicting wildfire spread behavior is an extremely important task for many countries. On a small scale, it is possible to ensure constant monitoring of the natural landscape through ground means. However, on the scale of large countries, this becomes practically impossible due to remote and vast forest territories. The most promising source of data in this case that can provide global monitoring is remote sensing data. Currently, the main challenge is the development of an effective pipeline that combines geospatial data collection and the application of advanced machine learning algorithms. Most approaches focus on short-term fire spreading prediction and utilize data from unmanned aerial vehicles (UAVs) for this purpose. In this study, we address the challenge of predicting fire spread on a large scale and consider a forecasting horizon ranging from 1 to 5 days. We train a neural network model based on the MA-Net architecture to predict wildfire spread based on environmental and climate data, taking into account spatial distribution features. Estimating the importance of features is another critical issue in fire behavior prediction, so we analyze their contribution to the model’s results. According to the experimental results, the most significant features are wind direction and land cover parameters. The F1-score for the predicted burned area varies from 0.64 to 0.68 depending on the day of prediction (from 1 to 5 days). The study was conducted in northern Russian regions and shows promise for further transfer and adaptation to other regions. This geospatial data-based artificial intelligence (AI) approach can be beneficial for supporting emergency systems and facilitating rapid decision-making.

Analysis of Fire Alarm Performance Effectiveness in MV. Rajakarta

Fires on ships pose a high risk due to limited access to help from land and firefighting equipment. To minimize these risks, it's important to maximize the effectiveness of the fire alarm system. This can be done by quickly detecting any smoke or fire using the alarm system and taking immediate action before the fire spreads. A qualitative descriptive method was used in this research to investigate the decline in the working function of fire alarms. The research focused on the problems with fire alarm smoke detectors and the correct maintenance methods. The findings of the research indicate that the lack of maintenance and repair of the fire alarm system are the main factors that cause the decline in the capability of fire alarm sensors. To ensure that the fire alarm system works properly, it should be routinely and periodically maintained. This will help to prevent any potential issues and ensure that the alarm system is always functioning at its best.

Atmospheric turbulence observed during a fuel-bed-scale low-intensity surface fire

Abstract. The ambient atmospheric environment affects the growth and spread of wildland fires, whereas heat and moisture released from the fires and the reduction of the surface drag in the burned areas can significantly alter local atmospheric conditions. Observational studies on fire–atmosphere interactions have used instrumented towers to collect data during prescribed fires, but a few towers in an operational-scale burn plot (usually > 103 m2) have made it extremely challenging to capture the myriad of factors controlling fire–atmosphere interactions, many of which exhibit strong spatial variability. Here, we present analyses of atmospheric turbulence data collected using a 4 × 4 array of fast-response sonic anemometers during a fire experiment on a 10 m × 10 m burn plot. In addition to confirming some of the previous findings on atmospheric turbulence associated with low-intensity surface fires, our results revealed substantial heterogeneity in turbulent intensity and heat and momentum fluxes just above the combustion zone. Despite the small plot (100 m2), fire-induced atmospheric turbulence exhibited strong dependence on the downwind distance from the initial line fire and the relative position specific to the fire front as the surface fire spread through the burn plot. This result highlights the necessity for coupled atmosphere–fire behavior models to have 1–2 m grid spacing to resolve heterogeneities in fire–atmosphere interactions that operate on spatiotemporal scales relevant to atmospheric turbulence. The findings here have important implications for modeling smoke dispersion, as atmospheric dispersion characteristics in the vicinity of a wildland fire are directly affected by fire-induced turbulence.

Different wildfire types promoted two-step terrestrial plant community change across the Triassic-Jurassic transition

Frequent wildfires associated with emplacement of the Central Atlantic Magmatic Province (CAMP) are thought to have been important drivers of two significant changes in terrestrial plant communities and diversity during the Triassic-Jurassic Mass Extinction (TJME, ca. 201.51 Ma). ​However, it remains to be investigated whether these two changes are potentially related to different wildfire types. To better understand this relationship, we used a new method to reanalyze fossil pollen and spores across the Triassic-Jurassic transition in the Jiyuan Basin from the North China Plate. Results show that two peaks in wildfire frequency experienced different types of wildfires, with each linked to significant changes in plant communities and diversity losses. In the first wildfire peak, canopy fires dominated and are accompanied by significant losses of canopy forming plants, while in the second wildfire peak, ground cover fires dominated accompanied by significant losses of ground cover plants. ​Changes in atmospheric humidity conditions were an important control on the two different wildfire peaks. Relatively humid climatic conditions corresponded to the prevalence of canopy fires and hindered the spread and development of ground cover fires in wet surface conditions. Conversely, relatively arid climatic conditions corresponded with the prevalence of ground cover fires in dry surface environments. Our results provide a potential relationship between terrestrial plant communities and wildfire types, which is important to further understanding of terrestrial environmental and floral changes driven by Large Igneous Provinces.

Evaluation of Fire Spread and Suppression Techniques in Micro-Mobility Battery Packs

Lithium-ion battery packs used in micro-mobility devices, such as e-bikes and e-scooters can lead to substantial safety hazards should a single cell go into thermal runaway. In this paper we explore the extent and severity of e-mobility battery fires resulting from a single cell thermal runaway failure and evaluate various suppression techniques a user may attempt to implement if they experience a battery fire at home. We tested a household water hose as well as different fire blankets deployed both before the forced thermal runaway event and after initiation. The water hose was unable to supply a sufficient amount of water to extinguish the thermal event, however, the average pack temperature was decreased and the cell-to-cell propagation rate was slowed. Neither fire blanket tested was able to contain the flames or debris ejected from the battery packs and both acted to hold in the heat from the event, increasing the temperature, rather than allowing it to dissipate. In addition, we also demonstrated how various design approaches, such as added thermal insulation between cells, can help prevent cell-to-cell propagation and reduce the severity of a battery pack failure.

Flame inhibition using nanotechnology

Flame inhibition is significant as it directly contributes to fire safety and prevention. Effective flame inhibition can reduce the spread and intensity of fires, protecting lives, property, and the environment. The research focused on the significant role of nanomaterials, specifically aluminum oxide (Al₂O₃), in improving fire retardation and enhancing fire inhibition performance. Nanoparticles can be used in flame inhibition, as they might merge two flame inhibition techniques: cooling and physical barriers. They offer unique properties due to their small size and high surface area, which can enhance their effectiveness in disrupting the combustion process. Nanoparticles can act as heat sinks, absorbing heat and reducing the temperature of the combustion zone (cooling method). They can also catalyze the formation of non-combustible gases or form a protective layer on the material's surface (physical method). Due to these properties, nanoparticles are increasingly studied and utilized for advanced flame retardant systems. Experimental work was carried out to accomplish the goal of the research. The fire inhibition test was performed within a pressure range between 3.2 and 5.3 cm of Hg, corresponding to a fuel-oxygen ratio of 9.3 % to 14.8 %, respectively. A novel nanoparticle material was involved in this analysis, including Al₂O₃. Based on the research analysis, the critical research results revealed that Al₂O₃ employment as a fire inhibitor provided a more enhanced impact of fire retardance and flame inhibition compared with conventional retardation materials, reflected in more sustainability and less adverse environmental effects.Furthermore, the experimental findings indicated that the flammability limits range between a lower flammability limit of approximately 9.3 % and an upper one of 14.8 % under specified amounts of pressure and temperature. In addition, increasing the inhibitor quantity could raise the lean flammability limit. Raising the nanomaterial mass would extend the flammability limits, altering the concentration of these nanoparticles to increase inhibitory effectiveness and change the lower and upper flammability limits.The study concluded that adjusting nanoparticle concentrations can significantly alter inhibitory effectiveness. The novelty lies in the use of a novel nanoparticle material, demonstrating improved sustainability and effectiveness in fire retardation of a highly flammable gaseous mixture.

Horizontal fire spread by foam-backed, polypropylene carpet

An eight year old boy was badly injured by a fire in his bedroom in May 2005. He spent his ninth birthday in intensive care and died a month later. This case study discusses a missing link into the pattern of fire development which made it difficult to identify the point of ignition. An absence of burning to the floor and isolated areas of burning seemed incongruous with the general pattern of fire development. Several fire investigation texts suggest that carpet cannot spread fire by itself; those texts that do mention the possibility, do not describe the mechanism in detail, nor what evidence an investigator might expect to see after the fire.Experimentation with samples of carpet gave good insight into the mechanism and its effects, thereby providing the missing link by which to connect the areas of burning and identify the point of origin. If elements of the mechanism described in this paper are known, a reader could discern enough from the many papers available to support a working hypothesis but as yet, there is no single paper that describes the phenomenon mechanistically from start to finish, especially to those who have not encountered elements of it before; hence, this paper presents some novel findings.The test involved polypropylene fibre carpets with integral polyurethane foam underlay, a very common type of carpet owing to its low cost and high durability. This is, therefore, an important mechanism of fire spread for fire investigators to be aware of and to understand. As this is a case study, rather than a research paper, the matters are dealt with empirically so the author cautions that when considering this mechanism in a new matter, the investigator should make their own tests of its validity.

Spatial and temporal patterns of forest fires in the Central Monte: relationships with regional climate

BackgroundNatural and anthropogenic wildfires burn large areas of arid and semi-arid forests with significant socio-economic and environmental impacts. Fire regimes are controlled by climate, vegetation type, and anthropogenic factors such as ignition sources and human-induced disturbances. Projections of climate and land-use change suggest that these controlling factors will change, altering fire regimes in the near future. In the southern Central Monte, Mendoza, Argentina, the factors that modulate the fire temporal and spatial variability are poorly understood. We reconstructed the fire history of southeast of Mendoza from 1984 to 2023 and investigated the relationships between fire extent and climate variability at seasonal and interannual scales. Burned areas were determined using Google Earth Engine by processing Landsat 5-TM, Landsat 7-ETM+ , and Landsat 8-OLI-TIRS sensor imagery.ResultsThe region exhibited high spatial and temporal variability in fire occurrence, being a mosaic of areas with different fire histories and recovery times. Between 1985 and 2023, fire recurrence ranged from sites unburned to sites with up to 14 fires. The occurrence of large fires was strongly favored by a combination of a year with abundant spring–early summer precipitation, which favors fuel accumulation, followed by a year of low spring–early summer precipitation. Precipitation and burnt area showed a very pronounced 6–7 year cycle, suggesting a dominant climatic control on fire occurrence.ConclusionsFire distribution in southeastern Mendoza forests is not homogeneous, resulting in a mosaic of patches with different fire histories. This heterogeneity may be related to vegetation patterns and land use. The temporal variability of fires is strongly influenced by climate variability, which would promote fuel production and subsequent drying. Large fires are concentrated in periods of high interannual precipitation variability. Climate change scenarios predict an increase in temperature and precipitation variability in the region, suggesting future changes in fire dynamics. Our results contribute to the development of fire guidelines for southeastern Mendoza forests, focusing on periods of wet years followed by dry years that favor fire occurrence and spread.

Trends and impacts of temperature and fire regimes in South Africa’s coastal national parks: implications for tourism

Climate change poses significant risks on coastal national park-based tourism through its effect on accessibility, comfort levels, and spatiotemporal changes of attractions. Wildfires and extreme temperatures have become issues of concern. Due to the widespread occurrence of fires in national parks along coastal areas and the noticeable changes in temperature regimes, more needs to be done to deepen understanding of their trends and impacts and devise appropriate management regimes. This study analyses the trends and impacts of fires and temperature-related variables in six coastal South African national parks, namely Agulhas, Garden Route, West Coast, Table Mountain, Namaqua, and Addo Elephant National Park. The triangulation and convergence model of the mixed-methods research design was adopted as the inquiry strategy. Data on statistical weather variables from the South African Weather Services and the National Aeronautics and Space Administration were used to calculate temperature trends using Mann–Kendall trend tests and homogeneity analysis. Data collection included questionnaire surveys, key informant interviews, field observations, and document analysis. The study observed statistically significant (p < 0.05) changes in temperature-related variables in all coastal national parks. There is also an increase in the intensity and spatial spread of fires, resulting in increased fire damage over time. Despite the current efforts of the coastal parks to manage wildfires and the changing climatic patterns, the fire and temperature regimes are threatening the biophysical environment with resultant effects on tourism and the economic viability of the national parks. The need to reengineer the fire suppression mechanisms and temperature-resilient tourism facilities has been observed.

Fire regimes of the Southern Appalachians may radically shift under climate change

BackgroundIncreased drought due to climate change will alter fire regimes in mesic forested landscapes where fuel moisture typically limits fire spread and where fuel loads are consistently high. These landscapes are often extensively modified by human land use change and management. We forecast the influence of varying climate scenarios on potential shifts in the wildfire regime across the mesic forests of the Southern Appalachians. This area has a long history of fire exclusion, land use change, and an expanding wildland urban interface. We considered interactions among climate, vegetation, and anthropogenic influences to forecast future fire regimes and changes to the forest structure. We used climate scenarios representing divergent drought patterns (overall drought trend and interannual variability) within a process-based fire model that captures the influence of climate, fuels, and fire ignition on wildfire patterns and suppression.ResultsCompared to simulations using historical climate (1972–2018), future total burned area (2020–2100: 782,302.7 (716,655.0–847,950.3) ha) increased by 42.3% under high drought variability (1,134,888.4 (1,067,437.2–1,202,339.6) ha), 104.8% under a substantial increase in drought trend (1,602,085.7 (1,511,837.5–1,692,334.0) ha), and 484.7% when combined (4,573,925.0 (4,434,910.5–4,712,939.5) ha). Landscape patterns of fire exclusion and suppression drove the spatial variability of fire return intervals (FRI). Our projections indicate wide spatial variability in future fire regimes with some areas experiencing multiple fires per decade while others experience no fire. More frequent fires corresponded with increased oak prevalence and a reduction in the biomass of mesic hardwoods and maple; however, mesic hardwoods remained prevalent under all fire intervals because of their contemporary dominance.ConclusionsOur study illustrates how future drought–fire–management interactions and a history of fire exclusion could alter future fire regimes and tree species composition. We find that increasing trends in drought magnitude and variability may increase wildfire activity, particularly in areas with minimal fire suppression. In ecosystems where fuel moisture (and not load) is the standard limitation to fire spread, increased pulses of drought may provide the conditions for more fire activity, regardless of effects on fuel loading. We conclude the effects of climate and human management will determine the novel conditions for both fire regime and ecosystem structure.

Brief communication: The Lahaina Fire disaster – how models can be used to understand and predict wildfires

Abstract. Following the destructive Lahaina Fire in Hawaii, our team has modeled the wind and fire spread processes to understand the drivers of this devastating event. The results are in good agreement with observations recorded during the event. Extreme winds with high variability, a fire ignition close to the community, and construction characteristics led to continued fire spread in multiple directions. Our results suggest that available modeling capabilities can provide vital information to guide decision-making and emergency response management during wildfire events.

Revealing Three-Dimensional Variations in Fuel Structures in Subtropical Forests through Backpack Laser Scanning

Wildfire hazard is a prominent issue in subtropical forests as climate change and extreme drought events increase in frequency. Stand-level fuel load and forest structure are determinants of forest fire occurrence and spread. However, current fuel management often lacks detailed vertical fuel distribution, limiting accurate fire risk assessment and effective fuel policy implementation. In this study, backpack laser scanning (BLS) is used to estimate several 3D structural parameters, including canopy height, crown base height, canopy volume, stand density, vegetation area index (VAI), and vegetation coverage, to characterize the fuel structure characteristics and vertical density distribution variation in different stands of subtropical forests in China. Through standard measurement using BLS point cloud data, we found that canopy height, crown base height, stand density, and VAI in the lower and middle-height strata differed significantly among stand types. Compared to vegetation coverage, the LiDAR-derived VAI can better show significant stratified changes in fuel density in the vertical direction among stand types. Among stand types, conifer-broadleaf mixed forest and C. lanceolata had a higher VAI in surface strata than other stand types, while P. massoniana and conifer-broadleaf mixed forests were particularly unique in having a higher VAI in the lower and middle-height strata, corresponding to the higher surface fuel and ladder fuel in the stand, respectively. To provide more informative support for forest fuel management, BLS LiDAR data combined with other remote sensing data were advocated to facilitate the visualization of fuel density distribution and the development of fire risk assessment.

Inorganic-Organic Antioxidant Gel for Preventing the Spread of Forest Fires

ABSTRACT It is easier and cheaper to prevent forest fires than to extinguish them, therefore, the development of long-lasting and environmentally friendly fire-retarding materials is highly desirable to prevent the spread of forest fires. In this study, soluble carboxymethyl starch replaced insoluble carboxymethyl cellulose to improve the compressive strength of inorganic gel and overcome the weakness of fragility. When the concentration of polymer carboxymethyl starch and crosslinking agent aluminum citrate were 0.5% and 0.3%, respectively, the inorganic/organic composite gel showed the best comprehensive performance (including gelation time, water retention, seepage velocity and strength). Additionally, the antioxidant tannin was introduced into the inorganic/organic gel, which effectively inhibited the oxidation of wood flour, making its inhibition rate reached 23.1%, about twice that of pure inorganic gel. This is mainly attributed to the ability of tannin to inhibit the oxidation process of active groups, including carbon-oxygen, hydroxyl, and methyl of the wood powder, thereby enhancing the flame resistance of the composite gel. Probable mechanism of forest fire suppression by the antioxidant composite gel is proposed, which involves oxygen isolation, evaporative cooling, and chain reaction inhibition.

The Effect of Fire on Multiple Tree Species in the Eastern Deciduous Forest

Fire is a disturbance that serves to maintain the diverse mosaic of vegetation in the Eastern Deciduous Forest. However, our ability to reconstruct fire occurrence from hardwood tree scars still lags far behind our expertise in reconstructing fire history from conifers in the western United States. This study examines the fidelity of fire scaring in multiple tree species in the Big Oaks National Wildlife Refuge in Indiana, which is located in the central hardwood region of the Eastern Deciduous Forest. All 15 species, except for red oak, showed evidence of past fires, and most samples recorded multiple fire events. No fire scars were recorded in the latewood of the samples. Most of the fires scars occurred in the earlywood (May) suggesting the dormant season fires are likely associated with fires in March to April before the growing season begins. No synchronous fires were recorded across all sites, but fires occurred in 1981, 1982, 1984, 1985, and 1988 across multiple sites. This suggests that these were larger spreading fires. Establishment pulses were documented in association with fire events in 1981, 1984, and 1995, suggesting that fire may benefit the establishment or root sprouting of some hardwood species. Fourteen of the fifteen species that we sampled preserved fire scars, suggesting that the diverse suite of species in the Eastern Deciduous Forest is a viable sampling pool for examining fire history across this forest type.

Consequences analysis of a natural gas pipeline: The case of the trans‐Anatolian natural gas pipeline

AbstractIndustrial accidents include fire, explosion, and toxic substance spread involving hazardous substances. They threaten the health of many people, cause permanent or long‐term pollution of the natural environment, cause a high degree of property damage, and require a large‐scale emergency response. Pipelines that transfer hazardous chemicals over a large area are risky for industrial accidents. In this study, we aimed to analyze the consequences of a possible industrial accident at the Edirne Ipsala compressor station in the trans‐Anatolian natural gas pipeline (TANAP). Analyses were carried out with the ALOHA software on two hypothetical scenarios: In Scenario 1, the chemical escapes from the pipe without the gas burning; and in Scenario 2, the chemical escapes from the pipe with the gas burning (jet fire). In the analysis of overpressure effects, TNT EM and TNO MEM were used besides the software. The largest effect distance (≈5000 m) was determined in the flammable area as a result of Scenario 1, and the prominent hazard property of the chemical was supported. The overpressure effects obtained with TNO MEM and the software were compatible with each other, but the values obtained with TNT EM were less severe and quite different. In the analysis of overpressure effects, it is shown that the ALOHA software provided more conservative results and that buildings would collapse and lethal effects might occur at a distance of 1000 m from the source. ALOHA produced outputs integrated with GIS by providing thermal radiation and toxic effect threat zones as well as overpressure effects. ALOHA turns out to be a more convenient and practical tool for risk assessment studies and emergency plans.

Large eddy simulations fire modeling of JIS A 1310 façade calibration test with respect to sidewall

AbstractThe full‐scale façade standard test is widely employed as a comprehensive method to assess the façade fire spread. Within this approach, the calibration test without combustible façade decouples the intricate interaction between gas‐phase combustion and material pyrolysis, which simplifies diagnostics and provides an ideal scenario for model validation. This paper presents large eddy simulations (LES) accompanied by comparisons of calibration tests in accordance with JIS A 1310. The calibration tests were conducted to obtain the flame morphologies, gas‐phase temperature, and heat flux of over‐ventilated façade fires, and the LES modeling is complemented by the modified eddy dissipation model for combustion, the one‐equation model for the sub‐grid scale turbulence, and the discrete ordinate method with the gray mean absorption‐emission approach for thermal radiation. The accuracy of LES data is discussed by comparing with measurements, and the mesh resolution is optimized as 2.5 cm for achieving mesh independency with good qualitative agreement. Furthermore, simulations are conducted to investigate the impact of sidewall distances on façade flame spread. The results highlight that the enhancement of sidewall in façade flame spread occurs under external heat release rate, and the 0.2 m sidewall distance for the designated JIS test is identified as a critical threshold increasing façade thermal load.