Fire Power Research Articles

Smoke dispersion test and emergency control plan of fire in mine roadway during downward ventilation

To explore the wind flow turbulence and smoke flow diffusion law during the mine downward ventilation fire, two similar experimental platforms of a inclined single pipe test device and a loop system multiple pipe test device were built. The change data of the air flow in the pipeline during the fire period under different air volumes were measured. The evolution process of downward ventilation fire in the whole roadway network domain in Dayan Mine was simulated, and the emergency plan was put forward. The results show that in the experiment, the combustion intensity of the fire source is positively correlated with the ventilation power, and the fire wind pressure increases with the increase of the inclination angle of the pipeline. The throttling effect of the fire area and the combustion of the fire source together make the air volume in the pipeline change rapidly. The critical wind speed that makes the downward ventilation flow fire wind pressure equal to the fan power is 1.8 m s−1. The stronger the fan capacity, the stronger the ability of the main air path to overcome the resistance of the fire zone and maintain the original state. In the simulation, the most dangerous place when the downward ventilation fire smoke is reversed is the area (weak flow area) in the mine tunnel network where the ventilation power is weaker than the fire wind power. This study can provide a theoretical basis for the formulation of emergency plans for mine fire accidents.

Evaluating the Thermal Performance of Steam Condenser Heat Exchanger in a Coal Fired Power Plant System

Evaluating the Thermal Performance of Steam Condenser Heat Exchanger in a Coal Fired Power Plant System

A Novel Emergency Lighting System Design Eliminating Extra Phase Line Installation

The emergency lighting system (ELS) is mandatory to be installed at the commercial, residential, and public buildings and must be activated automatically in the case of disasters such as fire, earthquake, flood, hurricane, and electricity power outage situations. Conventional ELS must use an extra phase line to charge its battery as well as to detect the presence of an emergency condition. It is costly to use an additional phase line in the electrical system and requires a new system configuration in the existing systems. In this study, an ELS design is proposed that eliminates the need for additional phase line installation by using power line communication (PLC) circuitry. Additionally, LED lamp is preferred instead of fluorescent lamp due to their advantages. The proposed ELS detects the presence of emergency and power outage conditions and then charges the battery of the system through the PLC.

Biomass burning CO, PM and fuel consumption per unit burned area estimates derived across Africa using geostationary SEVIRI fire radiative power and Sentinel-5P CO data

Abstract. We present the first top-down CO fire emissions inventory for Africa based on the direct relation between geostationary satellite-based fire radiative power (FRP) observations and polar-orbiting satellite observations of total column carbon monoxide (TCCO). This work significantly extends the previous Fire Radiative Energy Emissions (FREM) approach that derived total particulate matter (TPM) emission coefficients from FRP and aerosol optical depth (AOD) observations. The use of satellite-based CO observations to derive biome-specific CO emission coefficients, ECCOb, addresses key uncertainties in the use of AOD observations to estimate fire-generated CO emissions including the requirement for a smoke mass extinction coefficient in the AOD to TPM conversion and the large variation in TPM emission factors – which are used to convert TPM emissions to CO emissions. We use the FREM-derived CO emission coefficients to produce a pan-African CO fire emission inventory spanning 2004 to 2019. Regional CO emissions are in close agreement with the most recent version of GFED(v4.1s), despite the two inventories using completely different satellite datasets and methodologies. Dry matter consumed (DMC) and DMC per unit burned area are generated from our CO emission inventory – the latter using the 20 m resolution Sentinel-2 FireCCISFD burnt area (BA) product for 2019. We carry out an evaluation of our FREM-based CO emissions by using them as input in the WRF-CMAQ chemical transport model and comparing simulated TCCO fields to independent Sentinel-5P TROPOMI TCCO observations. The results of this evaluation show FREM CO emissions to generally be in good agreement with these independent measures – particularly in the case of individual fire-generated CO plumes, where modelled in-plume CO was within 5 % of satellite observations with a coefficient of determination of 0.80. Modelled and observed total CO, aggregated over the full model domain, are within 4 % of each other, though localised regions show an overestimation of modelled CO by up to 50 %. When compared to other evaluations of current state-of-the-art fire emissions inventories, the FREM CO emission inventory derived in this work shows some of the best agreement with independent observations. Updates to previously published FREM TPM emissions coefficients based on this methodology are also provided, along with a similar evaluation as conducted for CO. The methodology described in this work is forming the basis of a forthcoming near-real-time fire emissions product from Meteosat to be issued by the EUMETSAT LSA SAF (https://landsaf.ipma.pt/en/, last access: 19 December 2022).

Properties of pervious concrete incorporating fly ash as partial replacement of cement: A review

Disposing fly ash in to landfill of coal fire power plant initiated environmental and health problems. A lot of researchers have conducted research to study the addition of fly ash (FA) as cement replacement in pervious concrete (PC). The aim of this paper was to review the impact of adding FA as partial substitution of cement in PC. The experimental outcomes from different previous studies have indicated that the void content and permeability of PC decreased with adding FA due to filler effect of FA. The optimum substitution level of cement with FA was obtained to be 10–30%. However, with increasing the level of replacement affects the hydration procedure resulting lower strength. PC containing FA showed higher abrasion resistance and lower drying shrinkage compared to normal PC. It can be concluded that using FA as partial substitution of cement would be environmentally friendly in association with more sustainable PC.

Effect of incident light beam conditions on firing characteristics of the radial-firing optical fiber tip

Effect of the incident light beam conditions, such as the beam profile, the beam size, and the incident angle on the beam propagation and the firing characteristics of the radial-firing optical fiber tip comprised of conically shaped air pocket was investigated by the simulation using the ray-tracing method. Regardless of the different Gaussian profiles of the incident beam, no significant difference in the maximum firing angle but a little increase in the firing power was found with the increase of the axial distance of the Gaussian profile. With the increase of the incident beam size, no significant difference in the maximum firing angle was found but the relative firing power decreased and the extent of the power decrease depended on the numerical aperture (NA) of the fiber. On the other hand, the incident beam angle (BA) dependence of the firing power was significant, decreased to 65.9% and 31.9% for the RFF tip of NA 0.12 and NA 0.22, respectively, with the increase of the incident BA from 0 deg to 12 deg but the maximum firing angles did not show much decrease, smaller than 5 deg. The present modified simulation considering the incident light beam size and angle clearly showed the very close power distribution of the firing beam with respect to the firing angle obtained by the experimental results.

One year of near-continuous fire monitoring on a continental scale: Comparing fire radiative power from polar-orbiting and geostationary observations

Geostationary and polar-orbiting remote sensors have different opportunities to observe wildfires. While polar-orbiting sensors have been favoured in wildfire observations, geostationary sensors offer a higher observation frequency. Here, we assess the utility of the Himawari-8 AHI geostationary product and compare it to established polar-orbiting observations from TERRA/AQUA MODIS and SNPP VIIRS for 12 months of fire activity in Australia (2019–2020). Fire Radiative Power (FRP) estimates from AHI (BRIGHT/AHI) are compared to the MODIS (MOD14/MYD14) and VIIRS (VNP14IMG) polar-orbiting products, through varying spatial and temporal aggregations. Results suggest that all products capture similar wildfire dynamics across the continent. For near-simultaneously observed hotspots, the agreement is high between BRIGHT/AHI and the individual polar-orbiting products (r = 0.74–0.77, p < 0.01). Land cover and region-specific comparisons show similar FRP estimate distributions between products, although with scale differences due to the varying spatial resolutions. Derived diurnal FRP cycles on the other hand, highlight the dense temporal information that BRIGHT/AHI offers in contrast to the other products. This is further emphasized with individual event comparisons, where BRIGHT/AHI reports fire activity continuously while the polar-orbiting products only offer fragmented observations when available. In conclusion, AHI observes similar spatiotemporal patterns and FRP estimation distributions to MODIS and VIIRS during different seasons across Australia. While BRIGHT/AHI’s coarser spatial resolution underestimates the FRP estimations captured by its counterparts, its higher observation frequency demonstrates significant advantages. This analysis further raises the confidence in BRIGHT/AHI for continuous wildfire monitoring across Australia while revealing new opportunities that take advantage of its denser observation record.

Designing a modified Tchar stove and evaluation of its thermal performance

In this research, we have developed an energy-efficient modified version of the traditional Tchar stove for household use. The gasifier and charcoal stoves of a traditional Tchar have been incorporated into a single structure by movable fuel bed and pot support for the ease of operation .Traditional Tchar stove utilizes unidirectional preheated secondary air stream, which is unable to reach the flame core efficiently, and results in poor combustion. The modified Tchar stove under this study was designed with the provision of two preheated secondary air streams from opposite direction for crossflow mixing of secondary air and gaseous fuel for improved combustion. The characteristics parameters of the modified Tchar stove were measured following the standard water boiling test (WBT) method to compare with previously reported models. The high power (cold start), and simmering phases were used in WBT for the evaluation of the thermal performance of the modified Tchar stove. The thermal efficiency of the Tchar stove was 39.64±2.29% for the cold start high power phase and 51±3.12% for the low power simmering phase, respectively. In the cold start high power phase, the specific energy consumption values ranged from 1465.99 to 1855.9 kJ/liter. The thermal efficiency of the modified Tchar stove increased with decreasing firepower (kW). The designed stove allows enhanced heat transfer both at low and high fire power with its moveable structure. Moreover, it gives better combustion due to the cross-flow air mixing, which makes it a better alternative compared to the traditional Tchar stove.

Fire Influence on Regional to Global Environments and Air Quality (FIREX‐AQ)

AbstractThe NOAA/NASA Fire Influence on Regional to Global Environments and Air Quality (FIREX‐AQ) experiment was a multi‐agency, inter‐disciplinary research effort to: (a) obtain detailed measurements of trace gas and aerosol emissions from wildfires and prescribed fires using aircraft, satellites and ground‐based instruments, (b) make extensive suborbital remote sensing measurements of fire dynamics, (c) assess local, regional, and global modeling of fires, and (d) strengthen connections to observables on the ground such as fuels and fuel consumption and satellite products such as burned area and fire radiative power. From Boise, ID western wildfires were studied with the NASA DC‐8 and two NOAA Twin Otter aircraft. The high‐altitude NASA ER‐2 was deployed from Palmdale, CA to observe some of these fires in conjunction with satellite overpasses and the other aircraft. Further research was conducted on three mobile laboratories and ground sites, and 17 different modeling forecast and analyses products for fire, fuels and air quality and climate implications. From Salina, KS the DC‐8 investigated 87 smaller fires in the Southeast with remote and in‐situ data collection. Sampling by all platforms was designed to measure emissions of trace gases and aerosols with multiple transects to capture the chemical transformation of these emissions and perform remote sensing observations of fire and smoke plumes under day and night conditions. The emissions were linked to fuels consumed and fire radiative power using orbital and suborbital remote sensing observations collected during overflights of the fires and smoke plumes and ground sampling of fuels.

An experimental study on fire characteristics of urban complex underground space based on BIM

AbstractCompared with the space on the ground, if there is a fire in the urban complex underground space, the loss will be greatly harmful. In addition, the complex underground space is usually connected with other large space areas and densely populated. Once a fire occurs in the complex underground space, it will cause huge property losses and casualties. In order to reduce the risk of fire, it is necessary to deeply understand the development rules and characteristics of fire in the complex underground space of the city. This article has mainly carried on the following work: (I) A particularly complex model of the multi‐storey subway station was built. On this basis, three groups of comparative experiments were conducted to study the effects of fire power, fire location and smoke control system on fire development, and the conclusion that fire location is the most important factor for fire development was obtained; (II) In order to explore the entire space fire and the local space fire, CFD (Computational Fluid Dynamics) is used to build a large‐size fire model and a small‐size fire model respectively; (III) Multiple detector data as temperature slices were built, and it is expected to make full use of the simulation data to deduce the important index of fire location in the early stage of fire. All of the works in this paper will provide reference experimental data for the prevention and firefighting of a sudden fire in the complex underground space.

Influence of the Long-Range Transport of Siberian Biomass Burnings on Air Quality in Northeast China in June 2017.

Biomass burning (BB) emits a large volume of trace gases and aerosols into the atmosphere, which can significantly affect the earth's radiative balance and climate and has negative impacts on air quality and even human health. In late June 2017, an intense BB case, dominated by forest and savanna fires, occurred in Siberia, and it affected the air quality of Northeast China through long-range transport. Here, multisatellite remote-sensing products and ground-based PM2.5 measurements are used to evaluate the influence of the Siberian smoky plume on Northeast China. The results show that the BB was intense at the early stage when the daily fire count and average fire radiative power exceeded 300 and 200 MW, respectively. The maximum daily fire count reached 1350 in Siberia, and the peak value of instantaneous fire radiative power was as high as 3091.5 MW. High concentrations of CO and aerosols were emitted into the atmosphere by the BB in Siberia. The maximum daily mean values of the CO column concentration and aerosol optical depth (AOD) increased by 3 × 1017 molec·cm2 and 0.5 compared with that during the initial BB stage. In addition, the BB released a large number of absorptive aerosols into the atmosphere, and the UV aerosol index (UVAI) increased by five times at the peak of the event in Siberia. Under the appropriate synoptic conditions and, combined with pyroconvection, the smoky plume was lifted into the upper air and transported to Northeast China, affecting the air quality of Northeast China. The daily mean values of CO concentration, AOD, and UVAI in Northeast China increased by 6 × 1017 molec·cm2, 0.5, and 1.4, respectively, after being affected. Moreover, the concentration of the surface PM2.5 in Northeast China approximately doubled after being affected by the plume. The results of this study indicate that the air quality of Northeast China can be significantly affected by Siberian BBs under favorable conditions.

Vast ecosystem disturbance in a warming climate may jeopardize our climate goal of reducing CO2: a case study for megafires in the Australian ‘black summer’

A warming climate is one of the most important driving forces of intensified wildfires globally. The unprecedented wildfires broke out in the Australian ‘Black Summer’ (November 2019–February 2020), which released massive heat, gases, and particles into the atmosphere. The total carbon dioxide (CO2) emissions from wildfires were estimated at ∼963 million tons by using a top-down approach based on direct satellite measurements of CO2 and fire radiative power. The fire emissions have led to an approximately 50–80 folds increase in total CO2 emission in Australia compared with the similar seasons of 2014–2019. The excess CO2 from wildfires has offset almost half of the global anthropogenic CO2 emission reductions due to the Corona Virus Disease 2019 in 2020. When the wildfires were intense in December 2019, they caused a 1.48 watts per square meter additional positive radiative forcing above the monthly average in Australia and the vicinity. Our findings demonstrate that vast ecosystem disturbance in a warming climate can strongly influence the global carbon cycle and hamper our climate goal of reducing CO2.

Sustainable Life Cycle Analysis (LCA) approach and Reduction of Potential Slagging, Fouling and Corrosion Problems in Boilers of Power Generation Systems at Coal - Fired Power Plants

Sustainable Life Cycle Analysis (LCA) approach and Reduction of Potential Slagging, Fouling and Corrosion Problems in Boilers of Power Generation Systems at Coal - Fired Power Plants

The relationship between wind speed and satellite measurements of fire radiative power

Background Satellite fire radiative power (FRP) products are a potential source of wildland fire growth measurements that could be used with gridded or observed weather data to study meteorological influences on wildfire behaviour. There is little research to date examining how FRP relates to weather. Aims The goal of this study is to explore the relationship between satellite wildland fire FRP measurements and wind speed. Methods We examine GOES-16 FRP data from the summer of 2018 in California, comparing it with winds from the CANSAC reanalysis to understand the relationship between wind and FRP. Examination focuses on statistical distribution of the data and results of two different approaches to relating FRP and wind speed. Key results FRP is log-normally distributed, and there are significant consequences to using conventional statistical techniques that assume normality. We propose an alternative framing of the wind speed–FRP relationship to preserve more information about the FRP distribution. Conclusions Use of FRP data for meaningful understanding of fire–weather interactions requires attention to the nature of the FRP empirical distribution. Implications Applying our alternative approach to relating wildland fire FRP to weather has the potential to retain much more information than conventional approaches, but requires careful examination of the FRP data in each study.

Development of Ammonia Combustion Technology Development for Coal Fired Power Station

Development of Ammonia Combustion Technology Development for Coal Fired Power Station

Visual Fire Power: An Algorithm for Measuring Heat Release Rate of Visible Flames in Camera Footage, with Applications in Facade Fire Experiments

This paper presents a novel algorithm, called Visual Fire Power, for measuring the heat release rate of a turbulent flame using video footage taken from two cameras, located at an approximate right angle to each other and at a known distance from the fire. By measuring the time-averaged volume of the fire, Visual Fire Power can measure heat release rate in situations where traditional calorimetry may be impractical (such as experiments outdoors), as well as uniquely providing a method for comparing the heat release rates of different flames in the same experiment, e.g. externally venting flames from different windows of the same compartment. The algorithm was benchmarked against synthetic data and calculated the volume of common solids with approximately 30% uncertainty. The relationship between volume and heat release rate was then calibrated from videos of burners at known heat release rates. These experiments were used to calculate the Orloff-DeRis constant gamma, which linearly relates flame volume and heat release rate. The value for gamma was found to be 1505pm 183 kW/m3. The algorithm was demonstrated on recordings of a standard Polish facade fire test. Improving the range of data measured in both fire testing and fire experiments could help to increase our knowledge of fire dynamics and provide better data for researchers and engineers in the future.

A Thermodynamic Study of a Conventional 500 MW Coal Fired Power Plant Hybridized with Solar Energy

In this work, an effort is made to evaluate the performance improvement and harmful emission reduction of a 500 Megawatt conventional coal-fired thermal power plant by installing a parabolic solar trough at the low pressure heater for regeneration. Here, parabolic solar troughs are used in place of LP heaters for heating the feed water before it enters the economizer of the boiler. As a result, the steam flow rate through turbines will increase, which boosts the work output and also decreases the overall coal consumption, resulting in a huge reduction of harmful emissions of various gases as well as a reduction in the investment cost on coal. As an outcome, the objective of this research is to develop a thermodynamic model that can be used to quantify improvements in network output, total thermal efficiency, and daily coal consumption while reducing ash generation, SO2, and CO2 emissions.

China under Western Aggression: Discourse Transformations, Identity Shifts, and National Reconstruction

Abstract Following the Opium Wars, traditional notions of China as encompassing “all under heaven” (tianxia 天下) and the “Sino-barbarian dichotomy” (huayi 華夷) could no longer be sustained. Under the pressure and intimidation of the Great Powers’ advanced warships and fire power, the Qing government signed the unequal treaties and China was forced to adopt Western conceptual reasoning, discursive language, and rules of conduct. Western knowledge and lexicon was successively translated into Chinese, affecting transformations in local discourse and society. As part of this process, Japanese texts, which contained a great volume of Chinese characters, became an important medium for the transmission of Western epistemology. During the first Opium War between China and England, the cultural and political hegemony of the Great Powers were demonstrated through debates over interpretations of the Chinese character yi 夷. During the Late Qing, Chinese intellectuals drew on their foundations in traditional Chinese lexicon to understand and adopt the foreign-derived words zhongzu 種族 (race) and minzu 民族 (nation). This process reflects both shifts in how Chinese people regarded collective identity and the various presumptions underlying state-building visions.

Characteristics of False-Positive Active Fires for Biomass Burning Monitoring in Indonesia from VIIRS Data and Local Geo-Features

In this study, we explored the characteristics of thermal anomalies other than biomass burning to establish a zone map of false-positive active fires to support efficient ground validation for firefighters. We used the ASCII file of VIIRS active fire data (VNP14IMGML), which provides attributes of thermal anomalies every month from 2012 to 2020 in Indonesia. The characteristics of thermal anomalies other than biomass burning were explored using fire radiative power (FRP) values, confidence levels of active fire, fire pixel areas, and their allocations to permanent geographical features (i.e., volcano, river, lake, coastal line, road, and industrial/settlement areas). The Tukey test showed that there was a significant difference between the mean FRP values of the other thermal anomalies, type-1 (active volcano), type-2 (other static land sources), and type-3 (detection over water/offshore), at a confidence level of 95%. Most thermal anomalies other than biomass burning were in the nominal confidence level with a fire pixel area of 0.21 km2. High spatial images validated these thermal anomaly types as false positives of biomass burning. A zone map of potential false-positive active fire for biomass burning was established in this study by referring to the allocation of thermal anomalies from permanent geographical features. Implementing the zone map removed approximately 13% of the VIIRS active fires as the false positive of biomass burning. Insights gleaned through this study will support efficient ground validation of actual forest/land fires.

Mathematical models for estimate of the ecological consequences of the impact of the pyrogenic factor on forest ecosystems

There is a need for the development of simple analytical mathematical models of the burning of large forest areas, necessary for the assessment of the ecological consequences of the impact of the pyrogenic factor. Purpose. Develop mathematical models describing the spread of large-scale forest fires aimed at estimate the ecological consequences of the impact of the pyrogenic factor. Methods. Analytical review of research on the problem, theoretical and computational, mathematical modeling. Results. The results of the main parameters analysis of large forest areas combustion are presented. These include the area covered by the fire, the duration of the fire, the burnout time, the specific mass of combustible materials, the energy and power of combustion, the specific calorific value, the intensity of combustion, the movement speed of the combustion front, the influx of combustible materials, etc. Simple analytical mathematical models of large forest areas combustion have been established. These include the following models: a model with a constant growth rate of the fire area, a two-dimensional model, a model with sectorial movement of the combustion front, a model with a linear growth of the length of the combustion front, a model with a quadratic growth of the change rate of the fire area, and a generalized model. A new fire intensity classification has been proposed, containing 1–7 points from extremely low to extreme intensity. The maximum area covered by the fire (10–100 thousand km2), combustion energy (1–10 EJ) and combustion power (0.1–1 PW) have been estimated. Conclusions. Simple analytical mathematical models of the combustion process of large forest surface areas, which are necessary for quantitative assessment of the ecological consequences of fires, have been developed.