Fire Simulation Research Articles

Self-compacting concrete strength evaluation using fire hawk optimization-based simulations

Self-compacting concrete strength evaluation using fire hawk optimization-based simulations

Modeling of Wildfire Digital Twin: Research Progress in Detection, Simulation, and Prediction Techniques

Wildfires occur frequently in various regions of the world, causing serious damage to natural and human resources. Traditional wildfire prevention and management methods are often hampered by monitoring challenges and low efficiency. Digital twin technology, as a highly integrated virtual simulation model, shows great potential in wildfire management and prevention. At the same time, the virtual–reality combination of digital twin technology can provide new solutions for wildfire management. This paper summarizes the key technologies required to establish a wildfire digital twin system, focusing on the technical requirements and research progress in fire detection, simulation, and prediction. This paper also proposes the wildfire digital twin (WFDT) model, which integrates real-time data and computational simulations to replicate and predict wildfire behavior. The synthesis of these techniques within the framework of a digital twin offers a comprehensive approach to wildfire management, providing critical insights for decision-makers to mitigate risks and improve emergency response strategies.

Enhancing wildfire detection: a novel algorithm for controllable generation of wildfire smoke images

Background The lack of wildfire smoke image data is one of the most important factors hindering the development of image-based wildfire detection. Smoke image generation based on image inpainting techniques is a solution worthy of study. However, it is difficult to generate smoke texture with context consistency in complex backgrounds with current image inpainting methods. Aims This work aims to provide a wildfire smoke image database for specific scenarios. Methods We designed an algorithm based on generative adversarial networks (GANs) to generate smoke images. The algorithm includes a multi-scale fusion module to ensure consistency between the generated smoke and backgrounds. Additionally, a local feature-matching mechanism in the discriminator guides the generator to capture real smoke’s feature distribution. Key results We generated 13,400 wildfire smoke images based on forest background images and early fire simulation from the Fire Dynamics Simulator (FDS). Conclusions A variety of advanced object detection algorithms were trained based on the generated data. The experimental results confirmed that the addition of the generated data to the real datasets can effectively improve model performance. Implications This study paves a way for generating object datasets to enhance the reliability of watchtower or satellite wildfire monitoring.

Planning and Evaluation of Water-Dropping Strategy for Fixed-Wing Fire Extinguisher Based on Multi-Resolution Modeling

The deployment of fixed-wing aircraft in fire-extinguishing operations represents a significant advancement in the domain of aviation emergency rescue. Addressing the challenge of enhancing firefighting efficacy, this study delves into the water-dropping strategies of fixed-wing extinguishers and provides a methodological framework for the strategic planning and assessment of water-dropping tactics, employing multi-resolution modeling. The formulation of the planning algorithm and the structure of the effectiveness evaluation index system are explained accordingly. The corresponding prototype system was designed, comprising four subsystems that utilized distinct resolution models: fire environment simulation, water-dropping point scheme planning, approaching path planning, and mission evaluation simulation. Case studies validate the system’s capability to forecast fire and smoke propagation, plan a water-dropping trajectory based on the fire line, optimize flight paths based on the trajectory, and simulate as well as evaluate the whole firefighting mission process. The above research comprehensively constructs the model, finishes the iterative optimization, and evaluates the water-dropping strategy by simulation. The technical path and methodological framework of studying water-dropping strategies are established. The outcomes of this study provide invaluable support for the parameter inversion design of the fixed-wing extinguisher, offering decision-making assistance to commanders and supplying training scenarios for new aviation crews.

Analytical study on fire resistance performance of precast concrete hollow-core slabs for electric vehicle fire in parking structures

This study evaluated the effects of fires that occur in internal combustion engine vehicles (ICEVs) and battery electric vehicles (BEVs) on the structural safety of hollow-core slabs (HCS) installed in parking structures. A fire simulation of a prototype parking structure was performed using the time–heat release rate curves of ICEVs and BEVs derived from fire experiments, and fire behavior and temperature history were derived according to the fire curve. Additionally, nonlinear finite element analysis was conducted using a general-purpose finite element analysis program, and the fire resistance performance of HCS was evaluated according to the fire curve and slab load ratio. In the case of a fire in ICEVs, the performance criteria of ISO 834–1 were met even at a slab load ratio of 0.7. However, in the case of a fire in BEVs, the standard for insulation was not met as the temperature change of the upper surface of HCS exceeded 180 K, and the load-bearing capacity was also not satisfied as the limiting deflection reached a slab load ratio of 0.7.

Research on the Propagation Law of Fire Smoke on the Working Face of a Belt Conveyor

In view of the spread and distribution of high-temperature toxic smoke on the working face during belt conveyor fires, the FDS was used to carry out numerical simulation, establish a belt conveyor fire simulation model, set up a variety of working conditions, and study the flue gas spread of the working face with different ignition source locations and different heat release rates. The results show that the flue gas reaching the working face varies greatly from different ignition source locations, and the smoke propagation time of the working face decreases first and then increases with the increase in the scale of the fire. The location of the fire source is from 0 to 700 m, and the visibility of the working face will drop to less than 3 m within 10 min, which seriously affects emergency evacuation; the maximum concentration of CO in the working face is proportional to the heat release rate, the fire source is less than 100 m away from the working face, and the temperature of the air inlet area of the working face is higher than 60 °C, which poses a great threat to personnel evacuation. When the fire source is less than 200 m away from the working face, the evacuees will encounter smoke damage on the working face, and when the fire scale reaches 4 MW and 6 MW, the CO concentration will have a great impact on the evacuation and make people incapacitated.

UNDERSTANDING THE LEVEL OF KNOWLEDGE AMONG NURSES ABOUT FIRE SAFETY IN TERTIARY CARE HOSPITAL LAHORE

Fire safety in healthcare facilities is an important but frequently disregarded part of hospital administration and patient care. Despite substantial study on different aspects of healthcare delivery, there is still a significant gap in understanding and measuring fire safety knowledge and practices among healthcare personnel, particularly in Pakistan's tertiary care facilities. Objective: The purpose of this study was to assess the degree of fire safety knowledge among medical personnel at a tertiary care hospital in Lahore, Pakistan, to identify any shortcomings that may affect their capacity to respond effectively in the event of a fire. Methods: A cross sectional quantitative descriptive study was conducted at Public Tertiary care hospital in Lahore involving 202 nurses. A customized questionnaire was administered to assess the participant’s fire safety knowledge, selected through successive sampling. Data analysis was performed using SPSS version 22.0, categorizing knowledge level as poor, average and good. Results: 85% of survey participants were aware of fire response procedures. However, only 15% knew the fire department contact numbers, and 25% were unaware that foam or water extinguishers are ineffective against grease fires. Additionally, a significant proportion of participants struggled to correctly identify different types of fire extinguishers (65%) and fire categories (50%). The finding underscore the importance of comprehensive fire safety training to address significant knowledge gaps. Conclusions: Healthcare institutions should develop comprehensive fire safety training programs that extend beyond basic emergency protocols. Regular fire drills and simulations should be held to check staff members' understanding and reinforce fire safety procedures. Administrators should examine and update fire safety protocols on a regular basis to reflect new technology, legislation, and lessons learnt from previous events.

Constitutive model and deterioration mechanisms of uniaxial compressive behavior for calcium aluminate cement-based UHPC under simulated fire temperatures

Constitutive model and deterioration mechanisms of uniaxial compressive behavior for calcium aluminate cement-based UHPC under simulated fire temperatures

Levels of Effectiveness of Water Curtain Equipment Applied When Mitigating Fire Compartment Installation of Logistics Facilities

Mock-up tests and fire simulations were performed to verify the effectiveness of water curtain equipment in mitigating fire compartment installation of logistics facilities. The radiant-heat-blocking effect of the water curtain equipment differed significantly based on the type of drencher head, and a blocking effect was observed. Additionally, the radiant temperature and heat flux were significantly reduced when the installation intervals of the drencher heads of the water curtain equipment were reduced. Therefore, improving the standards related to the water curtain equipment of logistics facilities, e.g., providing drencher head specifications, restricting the sizes of the openings, and narrowing the installation intervals of the drencher heads, is necessary to ensure the fire safety of water curtain equipment.

Assessing the Need for Additional Evacuation Measures in Deep Underground Stations

Underground railroad stations face evacuation challenges owing to the rapid spread of smoke and extended escape routes during fires. Evacuation in deeply underground domestic railroad stations relies solely on stairways, with no legal standards for additional evacuation methods. In contrast, international standards such as NFPA 130 and Japan’s Fire Protection Engineering Association (JAFPE) recommend using evacuation elevators as a supplementary means of evacuation. This study analyzed smoke behavior in deep underground railroad stations through fire simulations at the Soongsil University and Guryong station. It also examined additional evacuation measures to enhance evacuation safety through evacuation simulations. The results show that during a fire, smoke spread follows the same path as the passenger evacuation routes because of the chimney effect. Even with smoke control and ventilation systems in operation, smoke follows the same evacuation routes, such as stairways or escalators. Therefore, the study concluded that evacuation elevators should be installed as an additional means to improve evacuation efficiency, and placed in smoke-protected evacuation routes. The study also found that combining evacuation stairways and elevators significantly enhances the evacuation efficiency.

Where to start with climate-smart forest management? Climatic risk for forest-based mitigation

Abstract. Natural disturbances like windthrows or forest fires alter the provision of forest ecosystem services such as timber production, protection from natural hazards, and carbon sequestration. After a disturbance, forests release large amounts of carbon and therefore change their status from carbon sinks to carbon sources for some time. Climate-smart forest management may decrease forest vulnerability to disturbances and thus reduce carbon emissions as a consequence of future disturbances. But how can we prioritise the stands most in need of climate-smart management? In this study we adopted a risk mapping framework (hazard times vulnerability) to assess the risk to climate-related forest ecosystem services (carbon stock and sink) in forests prone to windthrow (in the Julian Alps, Italy) and forest fires (in the Apennines, Italy). We calculated hazard by using forest fire and windthrow simulation tools and examined the most important drivers of the respective hazards. We then assessed vulnerability by calculating current carbon stocks and sinks in each forest stand. We combined these values together with the calculated hazard to estimate “carbon risk” and prioritised high-risk stands for climate-smart management. Our findings demonstrate that combining disturbance simulation tools and forest carbon measurements may aid in risk-related decision-making in forests and in planning decisions for climate-smart forestry. This approach may be replicated in other mountain forests to enhance our understanding of their actual carbon vulnerability to forest disturbances.

Study on the Driving Factors of the Spatiotemporal Pattern in Forest Lightning Fires and 3D Fire Simulation Based on Cellular Automata

Lightning-induced forest fires frequently inflict substantial damage on forest ecosystems, with the Daxing’anling region in northern China recognized as a high-incidence region for such phenomena. To elucidate the occurrence patterns of forest fires caused by lightning and to prevent such fires, this study employs a multifaceted approach, including statistical analysis, kernel density estimation, and spatial autocorrelation analysis, to conduct a comprehensive examination of the spatiotemporal distribution patterns of lightning-induced forest fires in the Greater Khingan Mountains region from 2016–2020. Additionally, the geographical detector method is utilized to assess the explanatory power of three main factors: climate, topography, and fuel characteristics associated with these fires, encompassing both univariate and interaction detections. Furthermore, a mixed-methods approach is adopted, integrating the Zhengfei Wang model with a three-dimensional cellular automaton to simulate the spread of lightning-induced forest fire events, which is further validated through rigorous quantitative verification. The principal findings are as follows: (1) Spatiotemporal Distribution of Lightning-Induced Forest Fires: Interannual variability reveals pronounced fluctuations in the incidence of lightning-induced forest fires. The monthly concentration of incidents is most significant in May, July, and August, demonstrating an upward trajectory. In terms of temporal distribution, fire occurrences are predominantly concentrated between 1:00 PM and 5:00 PM, conforming to a normal distribution pattern. Spatially, higher incidences of fires are observed in the western and northwestern regions, while the eastern and southeastern areas exhibit reduced rates. At the township level, significant spatial autocorrelation indicates that Xing’an Town represents a prominent hotspot (p = 0.001), whereas Oupu Town is identified as a significant cold spot (p = 0.05). (2) Determinants of the Spatiotemporal Distribution of Lightning-Induced Forest Fires: The spatiotemporal distribution of lightning-induced forest fires is influenced by a multitude of factors. Univariate analysis reveals that the explanatory power of these factors varies significantly, with climatic factors exerting the most substantial influence, followed by topographic and fuel characteristics. Interaction factor analysis indicates that the interactive effects of climatic variables are notably more pronounced than those of fuel and topographical factors. (3) Three-Dimensional Cellular Automaton Fire Simulation Based on the Zhengfei Wang Model: This investigation integrates the fire spread principles from the Zhengfei Wang model into a three-dimensional cellular automaton framework to simulate the dynamic behavior of lightning-induced forest fires. Through quantitative validation against empirical fire events, the model demonstrates an accuracy rate of 83.54% in forecasting the affected fire zones.

Underground rescue path planning based on a comprehensive risk assessment approach

Fire incidents in underground environments, such as subway stations and shopping malls, pose significant hazards due to restricted ventilation and confined spaces. These conditions complicate rescue operations, particularly given the unpredictable nature of fires. Effective integration of fire risk assessment into rescue path planning is essential for ensuring both safety and operational efficiency. However, fire risk is inherently complex, varying across both temporal and spatial dimensions, and accurate assessment depends on precise fire situation inference. Despite advancements in fire simulation technologies, inconsistencies in geometric structures between computational units limit seamless integration with path planning models. Consequently, many existing studies rely on simplistic and less reliable linear fire inference models, compromising the safety of rescue operations. This paper addresses these challenges by proposing an underground rescue path planning method based on a comprehensive fire risk assessment, aimed at enhancing both safety and operational efficiency. A fire risk assessment approach, driven by fire situation inference, is introduced, employing a novel grid-matching transformation to capture the spatio-temporal dynamics of fire conditions using high-precision simulation software. Additionally, an improved A* algorithm is developed for real-time rescue path optimization, minimizing path risk based on the results of the risk assessment. The proposed method is validated through a detailed case study, demonstrating its effectiveness and reliability.

Stellar Metallicities and Gradients in the Faint M31 Satellites Andromeda XVI and Andromeda XXVIII

We present ∼300 stellar metallicity measurements in two faint M31 dwarf galaxies, Andromeda XVI (M V = −7.5) and Andromeda XXVIII (M V = –8.8), derived using metallicity-sensitive calcium H and K narrowband Hubble Space Telescope imaging. These are the first individual stellar metallicities in And XVI (95 stars). Our And XXVIII sample (191 stars) is a factor of ∼15 increase over literature metallicities. For And XVI, we measure 〈[Fe/H]〉=−2.17−0.05+0.05 , σ[Fe/H]=0.33−0.07+0.07 , and ∇[Fe/H] = −0.23 ± 0.15 dex Re−1 . We find that And XVI is more metal-rich than Milky Way ultrafaint dwarf galaxies of similar luminosity, which may be a result of its unusually extended star formation history. For And XXVIII, we measure 〈[Fe/H]〉=−1.95−0.04+0.04 , σ[Fe/H]=0.34−0.05+0.05 , and ∇[Fe/H]= −0.46 ± 0.10 dex Re−1 , placing it on the dwarf galaxy mass–metallicity relation. Neither galaxy has a metallicity distribution function (MDF) with an abrupt metal-rich truncation, suggesting that star formation fell off gradually. The stellar metallicity gradient measurements are among the first for faint (L ≲ 106 L ⊙) galaxies outside the Milky Way halo. Both galaxies’ gradients are consistent with predictions from the FIRE simulations, where an age–gradient strength relationship is the observational consequence of stellar feedback that produces dark matter cores. We include a catalog for community spectroscopic follow-up, including 19 extremely metal-poor ([Fe/H] < –3.0) star candidates, which make up 7% of And XVI’s MDF and 6% of And XXVIII’s.

Comparison of different geometry trees in fire simulation

AbstractWildfire simulations can help to better understand the dynamics and effects of forest fires. The basis of wildfire simulation is the tree-burning simulation. In this paper, the fire simulation of 7 different geometry Hungarian trees in the case of arson is presented. It was observed that the trees were burned down fast. The maximum mass loss rate and maximum heat release rate were larger as the tree was larger. The largest intensity fire could be observed in the case of the smallest tree. The maximum temperature was higher in the case of a large crown diameter. The maximum aerosol reached high pollutant concentrations. In the case of large crown height, the maximum CO2 concentration was higher. The results presented in this paper can be the basis of the following forest fire simulations.

Study on Multi-Parameter Variation of Smoke Flow in Inclined Roadway Fire

ABSTRACT Based on the fluid similarity theory, a “Mine inclined roadway fire simulation experimental system” with similarity ratio of 1:20 is established. The temperature, velocity, density and dynamic pressure of fire smoke under different inlet wind speed (0.5 m/s, 1.0 m/s, 1.5 m/s) were tested and analyzed, and the distribution of temperature, velocity, density and dynamic pressure of inclined roadway during fire was simulated and analyzed by Ansys numerical simulation software. The research shows that: The higher the inlet wind speed, the faster the heat diffusion and the temperature field tends to be flat and long, the wind speed changes in advance and the change is drastic, the gas density decreases, the dynamic pressure first decreases and then increases and then tends to stabilize, but the change trend of temperature, wind speed, gas density and pressure in the overall combustion process remains unchanged. The numerical analysis results are in good agreement with the experimental results. By studying the change law of smoke temperature, velocity, density and dynamic pressure of coal mine inclined roadway fire, the theory of coal mine roadway fire is further perfected, and the level of coal mine fire prevention and rescue is improved.

Forest management with fire simulation

In this work, we address a forest management problem for timber production with fire concerns, employing a novel simulation-based optimization approach wherein forest management is iteratively guided by the feedback from fire spread simulations.The forest management problem involves selecting an alternative prescription for each stand, subject to various restrictions (e.g. bounds on ecosystems services), to maximize the net present value. For each stand, prescriptions involve projecting forest conditions and outcomes using species-specific growth and yield models, combined with different fuel treatment scenarios. In each iteration, the optimization problem is solved. Fire travel times between adjacent points in a grid representing the forest are calculated, based on fuel models associated with the selected prescriptions and other conditions as wind and slopes. Fire spread is simulated for all potential ignitions. Fire paths with a rate of spread greater than a given threshold are identified and constraints are added to the forestry problem to exclude their associated prescriptions to be jointly selected. This problem is re-optimized and the process is repeated until there are no such paths.We describe computational experiments in a Portuguese forest showing how trade-offs between the net present value and the maximum fire rate of spread can be obtained. When too restrictive conditions are imposed on fire, the approach suggests a set of stands to become fire breaks. We also conducted experiments to demonstrate how the impact of the forest surroundings, as well as bounds on ecosystem services, can be evaluated with respect to these trade-offs.

Simulated fire and plant-soil feedback effects on mycorrhizal fungi and invasive plants

Simulated fire and plant-soil feedback effects on mycorrhizal fungi and invasive plants

A waypoint based approach to visibility in performance based fire safety design

In performance-based fire safety design, ensuring safe egress, e.g. by visibility of safety signs, is a crucial safety goal. Compliance with the building requirements is often demonstrated by simulations of smoke spread. Numerical models like the Fire Dynamics Simulator generally compute visibility as a local quantity using the light extinction coefficient, without the consideration of the actual light path to a safety sign. Here, visibility maps are introduced, providing an approach for post-processing fire simulation data. They indicate safe areas along egress routes, with respect to visibility. At each location, the available visibility is calculated using Jin’s empirical relation, as an integrated value of the extinction coefficient along the line of sight to the closest exit sign. The required visibility results from the distance between those points. Additional parameters like view angle or visual obstructions are considered. The presented method allows for temporal visibility assessment, e.g. in an ASET-RSET analysis.

An end-to-end framework for fire following earthquake simulation at regional scale: A case study on the 2024 Japan Noto Peninsula earthquake

Fire following earthquakes remains a significant and threatening hazard to communities in urban regions. Addressing this critical issue requires an effective simulation method that is suitable for widespread adoption. This paper presents a systematic end-to-end framework for simulating fire following earthquakes at a regional scale by integrating models and methods available in existing literature. Relevant theories and models are summarized and incorporated into the calculation workflow. The framework encompasses three key features: (1) GIS-based regional building data management, (2) physics-based fire simulation, and (3) high-fidelity visualization. The implementation of the framework is presented in a sequential and detailed manner, with a focus on its practicality and replicability. Each component of the workflow is designed to be adaptable, allowing for easy customization and improvement to accommodate unique site characteristics or the integration of new models through the introduction of sub-modules. To demonstrate the practicality of the proposed framework, a case study based on the recent 2024 Noto Peninsula earthquake in Japan is presented. The simulation results correspond well with the observed actual damage at the fire following earthquake disaster site, with an accuracy of 87.8 %, which validates the framework's accuracy and reliability in simulating fire following earthquakes.