Concentration Distribution Research Articles

Identification of serum metabolites associated with polybrominated diphenyl ethers (PBDEs) exposure in papillary thyroid carcinoma: a case–control study

As the most common endocrine cancer, thyroid cancer (TC) has sharply increased globally over the past three decades. The growing incidence of TC might be counted by genetics, radiation, iodine, autoimmune disease, and exposure to environmental endocrine–disrupting chemicals (EDCs). Polybrominated diphenyl ethers (PBDEs), being typical EDCs, have been widely utilized in plastics, electronics, furniture, and textiles as flame retardants since the 1980s, and research has indicated a significant correlation between their exposure and the risk of TC. Even so, PBDEs exposure impact on the metabolic signature for TC remains unexplored. In this study, eight congeners of PBDEs were determined in serum from 111 patents with papillary thyroid cancer (PTC) and 111 healthy participants based on case–control epidemiology using gas chromatography–atmospheric pressure chemical ionization–tandem mass spectrometry (GC-APCI–MS/MS). Based on the tertile distribution of total PBDEs concentrations in 59 participants, metabolomics analysis was further performed by ultra-high performance liquid chromatography coupled to hybrid quadrupole–Orbitrap MS. In the partial correlation analysis, the 29 identified metabolites were correlated with PBDEs exposure (P < 0.05). In addition, PBDEs disrupted the metabolism of glycerophospholipids, sphingolipids, taurine, and hypotaurine, indicating that neurotransmitters, oxidative stress, and inflammation are the vulnerable pathways affected in PTC. Furthermore, (±)-octopamine and 5-hydroxyindole, both of which modulate the actions of neurotransmitters, emerged as potential disturbed metabolite markers for TC following exposure to PBDEs. This study analyzed the impact of PBDEs on PTC in terms of the metabolic changes and further explored possible biomarkers, which helped us have a deep understanding of the possible mechanism of the effects of PBDEs on TC.

Numerical Simulation of the OFA Effect on Combustion in a 600 MWe Boiler with Centrally Fuel Rich Burners

ABSTRACT With the rapid development of renewable energy, the traditional coal-fired power generation plays an important role in peak regulation, which requires the boilers to operate at low load or even ultra-low load. In order to investigate the effect of over-fire air (OFA) ratio on the flow, temperature and component concentration distribution and the furnace exit parameters for utility boilers at ultra-low loads, a 600 MWe utility boiler with centrally fuel rich (CFR) burner technology is taken as the object of study, and numerical simulations are carried out for five operating conditions with different OFA ratios (0%–40%) at 25% of the boiler’s maximum continuous rating (BMCR) load. The results show that no obvious high-temperature region is formed in the furnace and the flow field distribution in the furnace exit area is not conducive to the stable combustion of pulverized coal when the OFA ratio is 0% and 10%. When the OFA ratio is 30%, the area of the high-temperature region in the furnace reaches its maximum. When the OFA ratio is 40%, the furnace exit NO concentration is only 94.54 ppm. With the increase of the OFA ratio from 0% to 40%, the temperature of the flue gas at the furnace exit decreases by more than 100 K, which may affect the stable operation of the Selective Catalytic Reduction (SCR) denitrification equipment. Taking into consideration the flow in the furnace, the combustion, the NO x emission, and other factors, the recommended OFA ratio is 20% ~30%.

Study on Vertical Distribution of Sediment Concentration in the Tidal Estuary

The vertical distribution of sediment concentration in estuaries is the core issue of suspended sediment transport. At present, there are many researches on the vertical distribution of sediment concentration in rivers, and a lot of results have been achieved, but that in estuaries is seldom studied. The Yellow River Estuary (YRE) and the Qiantang River Estuary (QRE) are typical tidal estuaries with strong erosion/deposition and high concentration in China. Under the action of alternating tidal flow, the suspended sediment transport shows significant time-varying and non-equilibrium transport characteristics. The vertical distribution of sediment concentration is quite different from that of ordinary rivers. This paper analyzes the vertical distribution of sediment concentration under the action of tidal currents based on the theory of sediment movement and diffusion. Compared with equilibrium sediment transport, the vertical distribution of sediment concentration only differs by one vertical distribution coefficient. Based on the analysis of the measured data, it is found that the vertical distribution of sediment concentration in the YRE and QRE is mostly exponential. Firstly, the multivariate relationship between the vertical distribution coefficient and the sediment saturation and suspension index is established by means of the measured water and sediment data of the QRE. The correlation coefficient &amp;lt;I&amp;gt;R&amp;lt;/I&amp;gt;&amp;lt;sup&amp;gt;2&amp;lt;/sup&amp;gt; was above 0.64, which has a good correlation. Finally, the established relationship was validated using measured water and sediment data from the YRE, and the results were basically consistent, indicating that the established formula for vertical distribution of sediment concentration is suitable for general tidal estuaries, and has a certain reference value for the simulation of sediment transport in the YRE and QRE.

Performance enhancement of vanadium redox flow battery with novel streamlined design: Simulation and experimental validation

Electrolyte utilization and the consequent concentration polarization significantly limit the potential increase in power density and contribute to electrode degradation in vanadium redox flow batteries during cycling. This study investigates a novel curvature streamlined design, drawing inspiration from natural forms, aiming to enhance the performance of vanadium redox flow battery cells compared to conventional square and rectangular flow-through cell designs. The simulated 3D single-cell model shows a notably superior uniformity in both current and species' concentration distribution within the streamlined design compared to the square and rectangular shapes. Experimental analysis conducted on 3D-printed flow frames demonstrated 2 % enhanced energy efficiency and 47 % improved capacity when compared to rectangular design at 150 mA cm−2, all achieved with minimal increase in pressure drop.

Information extraction of seasonal dissolved oxygen in urban water bodies based on machine learning using sentinel-2 imagery: An open access application in Baiyangdian Lake

Water bodies are crucial components of urban ecology. The development of rapid and timely water-quality assessment tools using easily measured variables is essential for the health management of urban water bodies. In this study, we focused on the dissolved oxygen (DO) of Baiyangdian Lake using 251 sets of empirically measured water quality data and corresponding Sentinel-2 satellite images. Nine machine learning algorithms were then used to develop a rapid detection algorithm for the spatial distribution of the DO concentration in Baiyangdian Lake. This study successfully applied these methods to invert the DO concentration in Baiyangdian Lake during spring, summer, and autumn. The results indicated that extra tree regression (ETR) provided the most accurate and stable results for inverting the DO concentration among the nine machine learning methods. In contrast, AdaBoost regression (ABR), Bayesian ridge regression (BRR), and support vector machines (SVM) exhibit relatively poor regression performance and lack sensitivity to DO concentrations. Moreover, the DO concentration in Baiyangdian Lake ranged from approximately 0 to 12 mg/L, with notable spatiotemporal variations. The highest overall DO concentration was observed in the spring, particularly in the southern region. The DO concentration significantly decreased during summer compared to that in spring, with higher values in the southwestern area and lower values in the northern region. The DO concentration reached its lowest value in autumn, with slightly higher values in the southern region. This study focused on the estimation and inversion of DO concentrations in the water bodies of Baiyangdian Lake. By introducing and comparing the performances of commonly used machine learning models, a rapid estimation of the DO concentration was achieved, thereby overcoming the limitations of traditional water quality monitoring methods in DO inversion. It not only intuitively explained the temporal and spatial variation patterns of DO concentration but also laid a foundation for further in-depth exploration of the interactions between DO and other water quality parameters.

Ventilation performance of induction displacement units in indoor spaces within cold regions

Efficient ventilation systems play a crucial role in reducing occupants' exposure to indoor contaminants, including particles potentially carrying viruses like SARS-CoV-2. Displacement ventilation systems have demonstrated their effectiveness in improving indoor air quality during cooling modes. However, traditional displacement ventilation systems often struggle to achieve satisfactory distribution of contaminant concentrations during heating modes. To address this issue, this study focused on enhancing the ventilation performance of a dual-coil displacement-induction unit. Through a combination of experimental measurements and computational fluid dynamic (CFD) techniques, the study examined airflow and contaminant concentration distributions in an environmental chamber conditioned by these units. The results demonstrated good agreement between measured and simulated data, validating the CFD model. Further evaluation in a 25-occupant classroom under cold outdoor conditions showed that the dual-coil unit could achieve satisfactory ventilation performance in heating modes with proper design, comparable to traditional displacement ventilation in cooling modes. Additionally, the unit's versatility allows it to accommodate a wide range of air conditioning applications, from heating to cooling, making it a promising solution for displacement ventilation in various environments.

A comprehensive evaluation of crumb rubber modified asphalt-aggregate interfacial behavior and the effect of water: Molecular dynamics simulation and experimental investigation

The incorporation of crumb rubber (CR) makes the asphalt-aggregate interfacial properties highly complex and uncertain, while water is a key environmental factor causing interfacial failure. This paper aims to evaluate the characteristics of crumb rubber modified asphalt (CRMA)-aggregate interaction and the interfacial failure mechanism under the influence of different material properties and water at ambient temperature. Firstly, the CRMA-aggregate interfacial behavior before and after water intrusion is investigated using molecular dynamics simulations at the molecular scale. Next, the failure process and characteristics of the CRMA-aggregate interface were analyzed using the disk-shaped compact tension (DCT) test at the macro scale. Finally, the effect of water intrusion on the interface failure mode was analyzed through image processing. The results show that CR enhances binder cohesion and significantly affects its adhesion to aggregates with high CaO and MgO contents regardless of the presence of water. The asphalt concentration distribution on the CaO and MgO surfaces is more concentrated with higher peak concentration, leading to superior interfacial adhesion and water damage resistance with binder, while Al2O3 and SiO2 were inferior. The use of asphalt with higher creep stiffness, high-strength alkaline aggregates, and smaller CR particle size is beneficial for enhancing the CRMA binder-aggregate interfacial fracture performance. Water intrusion severely affected the interfacial adhesion, resulting in a significant increase in the proportion of adhesion failure, which is the main cause of the deterioration of the interface properties. The findings of this study provide insights into the factors affecting the CRMA-aggregate interfacial behavior, which facilitate the accurate design and application of high-strength durable CRMA mixtures.

Experimental Study on Explosion Characteristics and Consequences for Homogeneous and Inhomogeneous Methane-Air Mixtures within a Kitchen

ABSTRACT Owing to the effect of a non-uniform concentration distribution, natural gas leakage explosion accidents usually cause different degrees of damage inside residential kitchens. According to the similarity principle, a reduced-scale experiment setup of a kitchen was established. Uniform and non-uniform explosion experiments for methane-air mixtures with concentrations of 7.7%, 9.5%, and 11.2% were performed. The flame propagation behavior and pressure evolution characteristics were analyzed for homogeneous and inhomogeneous methane-air mixtures. In addition, two dimensionless coefficients, namely macroscopic and directional non-uniformity coefficients, were introduced to quantify the uneven distribution of gas concentration within the kitchen. Furthermore, the flame development process and pressure evolvement characteristics were compared between homogeneous and inhomogeneous methane-air mixtures in a fuel-lean, chemical equivalence concentration and fuel-rich state. The results show that the macroscopic non-uniformity coefficients are 0.0998, 0.0653, and 0.0571 on the fuel-lean, chemical equivalence concentration and fuel-rich conditions, respectively. It indicates that the greatest non-uniformity of methane concentration distribution within the kitchen is represented on the fuel-lean condition. The concentration gradient could obviously reduce the explosion overpressure in the fuel-lean condition, whereas it would not significantly decrease the explosion overpressure in the chemical equivalence concentration or fuel-rich condition. It means that the greater the non-uniformity coefficient is, the more significant the effect on the overpressure peak is.

Spatial Mapping of Air Pollution Hotspots around Commercial Meat-Cooking Restaurants Using Bicycle-Based Mobile Monitoring

Mobile measurement techniques are increasingly utilized to monitor urban emissions, regional air quality, and air pollutant exposure assessments. This study employed a bicycle measurement method to obtain the detailed distribution of air pollutant concentrations in roadside, commercial, residential, and recreational areas. The study area is located in Chuncheon, South Korea, with approximately 280,000 residents. Black carbon (BC), PM2.5, and NO2 were monitored using portable devices equipped on an electric bicycle. Results showed that in the evening (6–8 p.m.), the concentrations were higher in both commercial and residential areas compared to the background location, while concentrations were notably elevated only in roadside areas in the morning (8–10 a.m.). Spatial mapping of measured concentrations revealed that the highest concentrations corresponded to areas with densely operated charbroiling meat-cooking restaurants. Additionally, it was confirmed that BC and PM2.5 emitted from the commercial areas influenced nearby recreational areas (e.g., streamside roads). In conclusion, this study demonstrated that air pollutant hotspots resulting from human activities, such as dining at commercial restaurants, significantly worsen the local air quality on a small scale. Efforts to reduce the uncontrolled emissions of air pollutants from charbroiling meat-cooking restaurants are necessary.

Abnormal erythrocyte-related parameters in children with Pb, Cr, Cu and Zn exposure.

The link between exposure to a particular heavy metal or metalloid and the development of anemia is well established. However, the association between combined exposure to multiple heavy metal(loid)s and anemia in children is still lacking in evidence. In this study, a total of 266 children aged3 to7 were recruited from Guiyu, China. Inductively coupled plasma mass spectrometry (ICP-MS) was used to measure bloodheavy metal(loid)concentrations. Blood cell count, hemoglobin (HGB), mean corpuscular hemoglobin (MCH), mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), hematocrit (HCT), and red blood cell distribution width (RDW) were measured by an automated hematology analyzer. Erythrocyte-related parameters were negatively correlated with the Cu and Cu/Zn ratios and positively correlated with Cr, Ni, Zn, and Se by Spearman correlation analysis. Only blood Cu level was negatively correlated with HGB [β = -2.74, (95% Cl: -4.49, -0.995)], MCH [β = -0.505, (95% Cl: -0.785, -0.226)], MCV [β = -1.024, (95% Cl: -1.767, -0.281)], and MCHC [β = -2.137, (95% Cl: -3.54, -0.734)] by multiple linear regression analysis. TheBayesian Kernel Machine Regression (BKMR) model analysis indicated a negative correlation between the combined exposure to Cu, Zn, Pb, and Cr and MCH and MCV. The single-factor analysis showed a considerable statistical difference only with Cu on MCV, MCH, and HGB. Furthermore, the interaction analysis highlighted the interdependent effects of Cu and Zn, Pb and Zn, and Cr and Zn on MCH and MCV levels. Additionally, the oxidation and/or antioxidation reactions may play a significant role in the development of metal(loid)-induced anemia risk. It is crucial to investigate the effects of co-exposure to multiple heavymetal(loid)elements on anemia, especially the interrelationships and mechanisms among them.

Experimental investigation and molecular dynamics study on the influence of non-ionic fluorocarbon solutions on the fast-wetting mechanism of coal dust

To explore methods for enhancing the wetting performance of coal dust to mitigate its hazards, this study selected four different structures of non-ionic fluorocarbon solutions: perfluorinated propyl acrylate (PFPA), perfluorooctyl acrylate (PFTA), perfluorooctyl sulfonyl phenyloxy ethyl methylacrylate (PPM), and perfluoro propanoic acid (PFA). The dynamic wetting performance and mechanisms of these solutions on coal dust were measured and analyzed through kinetic calculations. The results indicate that all four fluorocarbon solutions achieve optimal wetting performance at a concentration of 0.3 %. Comprehensive analysis shows that their wetting ability follows the order PFPA > PFTA > PPM > PFA. Further analysis reveals that coal dust treated with PFPA shows an increase in structures such as COOH and CO. The relative concentration distribution indicates partial overlap between the fluorocarbon solution and water, with an overlap range of 8.2 Å. Additionally, the maximum diffusion coefficient is 0.577 Å/ps, and the system’s adsorption energy is the highest at −5757.25 kcal/mol.

CFD modeling investigation of oxy-fuel combustion application in an industrial-scale FCC regenerator

The increase in atmospheric CO2 concentration and its consequential impact on climate change have elicited increased public concern. The refinery units including fluid catalytic cracking (FCC) generate substantial quantities of CO2. To mitigate the emission from the FCC process, oxy-fuel combustion has emerged as a prospective carbon capture and storage technology. This study presents the first trial for the modeling investigation of a 70 kt/a industrial FCC regenerator under the scenario of retrofitting it with oxy-fuel combustion technology. Employing the Eulerian-Eulerian model, a CFD model integrating heat transfer and coke combustion reactions has been established. The detailed hydrodynamics, temperature, and species concentration distribution inside the regenerator are obtained under both air-firing and oxy-firing conditions, which are further compared to exploit the possibility of oxy-fuel combustion retrofitting. As has been found, decreases in gas temperature and carbon conversion rate were observed for 21 % O2/79 % CO2 atmosphere in comparison to the air reference case due to the differences in gas properties between N2 and CO2. This discrepancy resulted in a drop of 17 K in dilute phase temperature and 2 K in dense phase temperature. The bed density also exhibited a large with the oxy-firing conditions, with notable observations revealing a lower bed density below a height of 4.2 m, transitioning to a higher density above said height. Sensitivity analysis was also conducted for three principal operating parameters, including superficial gas velocity, oxygen partial pressure, and catalyst circulation rate. An increase of oxygen partial pressure to 27 % or a decrease of the catalyst circulation rate to 20.7 kg/s proved effective in achieving the same temperature profile and even a slightly better carbon conversion in comparison to air-firing regeneration.

Experimental and numerical studies of the fuel concentration distribution within the near-wall area in a compact space for a gas turbine combustor

Interstage combustion is known for its small axial distance, high combustion efficiency and low lean blowout boundary. However, in a compact space, the distance between the fuel injection location and the wall is confined, and the high-temperature wall may affect the fuel distribution and in turn affect the combustion efficiency. In this study, an experiment of kerosene single-droplet evaporation was conducted, and the fuel distribution in an interstage combustor was numerically simulated. The experimental results showed that the evaporation rate of fuel droplets decreased with increasing distance from the high-temperature wall, and the influence of the lower wall on fuel evaporation was greater than that of the sidewall. The fuel evaporation rate at the high-temperature position within the nonuniform wall temperature field was relatively high. The numerical simulation results indicated that with increasing temperature, the effect of the wall on fuel evaporation increased, as did the uniformity of the fuel distribution. The direction of the temperature gradient imposed the greatest effect on the fuel distribution under nonuniform temperature conditions. This will facilitate the selection of the optimal ignition location within the cavity to achieve efficient combustion. Moreover, it's possible to control the fuel distribution by adjusting the wall temperature.

Indoor Concentration Distributions of Ammonia and Sulfur-Based Odorous Substances According to Types of Laying Hen Houses in South Korea

Indoor Concentration Distributions of Ammonia and Sulfur-Based Odorous Substances According to Types of Laying Hen Houses in South Korea

Measurement of engine exhaust plume temperature and concentration distributions with tomographic absorption spectroscopy and learning-based absorbance recovery

Measuring the spatial distribution of temperature and species concentration is important to the thermodynamic analysis and validation of modern combustion systems. In this work, we developed a measurement method based on tomographic absorption spectroscopy (TAS) for the quantitative measurement of two-dimensional distributions of gas temperature and concentration. A learning-based absorbance recovery method was proposed and incorporated into TAS to address the baseline error induced distortion of absorbance and improve the accuracy of single path measurement. The developed TAS system, consisting of 12 laser beams, was demonstrated on a diesel fueled small turbojet engine. Temperature and H2O concentration distributions of the exhaust plume were measured with laser wavelength scan rates of 20 kHz. Temperature variations in microsecond-scale were captured and the time-averaged center temperature agreed well with thermocouple measurements. The developed TAS method demonstrates the feasibility of real-time and accurate tomographic imaging for practical combustion flows, which could be effectively applied for widespread combustion diagnostics.

Design and experiment of a lightweight cloud particle imager

Abstract Accurate in-situ measurement of cloud microphysical parameters such as particle diameter, number concentration and droplet spectrum distribution are of great significance in cloud physics, climate change, numerical weather forecasting and weather modification. This work describes the design and characterization of a newly developed in situ measurement instrument for cloud and fog named lightweight cloud particle imager (LCPI). The basic measurement principle of LCPI is based on scattering light imaging of particles in a dark field. A ring LED lighting source was designed to improve the image quality. Field measurements were carried out at a high-altitude research station on Lushan Mountain. The measured size distributions showed good agreement with parallel measurements of a cloud droplet spectrometer (fog monitor-120). The field data also showed that LCPI was able to measure the size distribution of cloud droplets from 5 to 300 μm with a high spatial resolution. In addition, another observation experiment carried out in the Tuli River weather station showed that LCPI also had the ability to acquire clear images of ice crystal particles larger than 10 μm. Thus, LCPI provides an opportunity to simultaneously quantify the microphysical structure of different cloud types.

Characteristics of heat transfer in corrosion products deposited on the surface of pressurized water reactor fuel elements

The occurrence of porous deposits on the core surface during the operation of a pressurized water reactor can seriously affect its heat transfer characteristics and increase the surface temperature of the cladding. Continued heat transfer deterioration causes subcooled boiling and boron enrichment within porous deposits, leading to axial power anomalies in the core, and the study of porous deposits is beneficial to improving the economics and safety of reactor operation. In this paper, a two-dimensional boiling unit model of a porous deposits was established using COMSOL software to couple heat conduction, darcy flow, solute transport and chemical reactions in a multiphysics field to reasonably predict the temperature field, velocity field, boric acid concentration distribution, and PH distribution within the porous deposits. On this basis, the influence of different parameters (porosity, boiling unit radius of porous deposits, heat flow density) on the maximum effective thermal conductivity, the pattern of thermal parameters (temperature, superheat, percentage of subcooled boiling, and saturation temperature) on the chimney boundary are analyzed. The results show that localized superheating, maximum boric acid concentration and subcooled boiling occur at the bottom of the porous deposits. There is a negative correlation between the porosity and the percentage of subcooled boiling area, and a positive correlation between the radius of the porous deposits and the heat flow density and the percentage of subcooled boiling area.

Numerical simulation of high-pressure jet fire in on-board hydrogen storage cylinders under fire conditions

Hydrogen fuel cell vehicles (HFCVs) may cause fires in the event of an accident. When the high-pressure hydrogen storage cylinders are exposed to fire for a long time, there will be a risk of catastrophic consequences such as leakage, jet fire and explosion. Fire test is the main method to study the safety performance of hydrogen storage cylinders. During the firing process, the wall and internal temperature of the hydrogen storage cylinder rise gradually, and the thermally activated pressure relief device (TPRD) of the cylinder reaches a certain temperature and then releases high-pressure hydrogen to prevent the cylinder from bursting. As the hydrogen storage cylinder is in the fire environment, the release of high-pressure hydrogen will be ignited to form a jet fire and cause damage to personnel and equipment. In this paper, CFD software Fluent was used to numerically simulate the local fire test of the hydrogen storage cylinder with high-temperature air as the fire source. The variation law of cylinder wall temperature, gas temperature and pressure inside the cylinder, and the activation of TPRD were analyzed. At the same time, on the basis of the fire test simulation, a high-pressure hydrogen jet fire simulation numerical model caused by the TPRD action was established. The velocity field, temperature field and hydrogen concentration distribution of the jet fire were obtained, and the overpressure generated by the jet fire and the flame length size were analyzed. The results show that the high-pressure hydrogen released by TPRD was ignited under the fire condition to produce a jet flame and generated an overpressure in the jet direction, and the influence range of the overpressure was smaller than the influence range of the jet flame.

Highly efficient wide-bandgap perovskite solar cells prepared by fixing charge passivation in the interface layer

The severe stress on the surface of the wide-bandgap perovskite film will extend to the carrier transport layer (CTL)/metal electrode interface, leading to increased roughness of the CTL surface. This, in turn, adversely affects carrier transfer at the interface and compromises device stability. To address this issue, we devised a localized contact structure wherein molybdenum oxide (MoOx) interlayers of specific thickness were vacuum-deposited at the CTL/metal electrode interface to change the path of carrier transfer. Characterizations of the MoOx localized contact structure were done by Kelvin probe force microscopy, capacitance–voltage (C–V), electrochemical impedance spectroscopy, and x-ray photoelectron spectroscopy. It was observed that MoOx interlayer can generate negative fixed charges at hole transport layer/Ag interface, which changes the carrier concentration distribution, enhances the built-in voltage, and promotes the transfer of carriers near the interface. Compared to wide-bandgap perovskite solar cells (WB-PSCs, Eg = 1.65 eV) lacking the MoOx localized contact structure, the efficiency of the optimized device increased to 20.5%, accompanied by enhancements in overall performance parameters. Notably, the thermal and light stability of the unpackaged devices have been significantly improved.

Experimental and Numerical Study on the Plasma-Laser-Induced Ignition of Strut Stabilizer at Different Locations

The minimum ignition equivalence ratio of the strut stabilizer is an important parameter in the design of integrated afterburners. The ignition location significantly affects the ignition equivalence ratio and flame propagation, and therefore, it should be deeply studied. The ignition equivalence ratio and flame propagation at different axial ignition locations downstream of the strut stabilizer are studied in this paper. When the ignition distance is approximately the bluff body trailing edge width, a lower ignition equivalence ratio is required for ignition, and the flame propagates faster through the entire combustion chamber. For different ignition locations, the generated flame kernel at different locations all first propagates to the shear layer. Subsequently, the unilateral flame rapidly extends, ultimately igniting the entire combustion chamber. The flame propagation trajectory depends on the ignition location controlled by the non-reacting flow field and the distribution of kerosene concentration. The flame propagation trajectory mainly includes three paths: (1) the flame kernel is directly downstream the shear layer when the ignition location is close to the tail edge of the stabilizer, (2) the flame propagates upstream into the shear layer in a U-shape when the ignition location is far from the stabilizer but still in the recirculation zone, and (3) the flame propagates upstream into the recirculation zone and shear layer in a U-shape when the ignition location is outside the recirculation zone. In addition, the time for flame propagation to the shear layer is directly related to the ignition performance when the ignition location is within the recirculation zone. If the flame reaches the shear layer in a longer time, there will be more energy loss during the flame propagation process, and the ignition performance will deteriorate. The speed of the flame-trailing edge extension is directly related to the ignition fuel-air ratio, and the downstream extension of the flame is mainly affected by the turbulence velocity in the shear layer.