Combustion and Flame最新文献

{"title":"Study of chemiluminescence of methane–air flame stabilized on a flat porous burner","authors":"Anastasia Moroshkina, Evgeniy Sereshchenko, Vladimir Mislavskii, Vladimir Gubernov, Sergey Minaev","doi":"10.1016/j.combustflame.2024.113755","DOIUrl":"10.1016/j.combustflame.2024.113755","url":null,"abstract":"<div><div>In this work, the spatial distribution and spectral characteristics of the chemiluminescence of chemically excited species, OH<span><math><msup><mrow></mrow><mrow><mo>∗</mo></mrow></msup></math></span> and CH<span><math><msup><mrow></mrow><mrow><mo>∗</mo></mrow></msup></math></span>, are experimentally and numerically studied by using a stationary premixed methane–air flame stabilized on the surface of a flat porous burner for various equivalence ratio and normal pressure. Numerical simulations are carried out using detailed reaction mechanisms, and the experimental study includes high-resolution spatial and spectral optical measurements. Despite the data reported in the literature, it is found that (i) the rotational degrees of freedom of OH<span><math><msup><mrow></mrow><mrow><mo>∗</mo></mrow></msup></math></span> and CH<span><math><msup><mrow></mrow><mrow><mo>∗</mo></mrow></msup></math></span> are not in thermal equilibrium with the surrounding gas and therefore cannot be used to measure flame temperature; (ii) there is no direct correlation between the heat release rate and the distribution of OH<span><math><msup><mrow></mrow><mrow><mo>∗</mo></mrow></msup></math></span> and CH<span><math><msup><mrow></mrow><mrow><mo>∗</mo></mrow></msup></math></span>; (iii) the detailed reaction mechanisms not only quantitatively, and also qualitatively differ in description of the OH<span><math><msup><mrow></mrow><mrow><mo>∗</mo></mrow></msup></math></span> and CH<span><math><msup><mrow></mrow><mrow><mo>∗</mo></mrow></msup></math></span> concentrations. Since the chemically excited species are well localized in a direction normal to the flame surface, they are demonstrated to be a very accurate markers of flame location. The shape of the combustion front can be reconstructed and resolved up to the accuracy of tens of microns, which is very important for estimation of blow-off critical parameters and measurement of the laminar burning velocity.</div><div><strong>Novelty and significance statement</strong></div><div>Currently, there is a growing interest in the development of sensors for combustion control systems, including active control and suppression of instabilities, in combustion chambers of various devices and engines based on chemiluminescence of excited reaction species. The possibility of non-invasive determination of parameters such as flame temperature, stoichiometry, heat release rate location, etc. using this technique is discussed. We have found that most of these parameters cannot be estimated either due to fundamental limitations or insufficient knowledge of the reaction kinetics involved in the production of these species. Nevertheless, since OH* and CH* are well localized in the direction normal to the flame surface, they can be used as very accurate markers of flame shape and position, allowing us to reconstruct the flame surface to within tens of microns resolution, which is very important for estimating blow-off critical parame","PeriodicalId":280,"journal":{"name":"Combustion and Flame","volume":"270 ","pages":"Article 113755"},"PeriodicalIF":5.8,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Realization of a standing normal detonation for hypersonic propulsion","authors":"Adam Kotler ,&nbsp;Anthony Morales ,&nbsp;Sheikh Salauddin ,&nbsp;Daniel Rosato ,&nbsp;Mason Thornton ,&nbsp;Hardeo M. Chin ,&nbsp;Zachary White ,&nbsp;Kareem Ahmed","doi":"10.1016/j.combustflame.2024.113780","DOIUrl":"10.1016/j.combustflame.2024.113780","url":null,"abstract":"<div><div>A standing normal detonation mode of combustion consisting of a normal shock coupled with heat release is realized in an experimental high-speed reacting-flow facility. The normal detonation is stabilized using a 2D ramp where the high-enthalpy freestream Mach number and reactant composition is equivalently matched to the Chapman-Jouguet (CJ) consumption speed of the detonation, at <em>M_∞/M_CJ</em> = 1.06. High resolution optical measurements of OH* chemiluminescence and density gradients from schlieren clearly show the close-coupling between the normal shock and the heat release of the standing detonation. A ZND analysis have been conducted using the boundary conditions where the induction length is found to closely matches the experimentally measured induction length. The agreement between the induction length scales and the freestream Mach number to detonation CJ Mach number confirm the realization of a standing detonation mode of combustion.</div></div>","PeriodicalId":280,"journal":{"name":"Combustion and Flame","volume":"270 ","pages":"Article 113780"},"PeriodicalIF":5.8,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Publication / Copyright Information","authors":"","doi":"10.1016/S0010-2180(24)00473-5","DOIUrl":"10.1016/S0010-2180(24)00473-5","url":null,"abstract":"","PeriodicalId":280,"journal":{"name":"Combustion and Flame","volume":"269 ","pages":"Article 113764"},"PeriodicalIF":5.8,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142424850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Automatization of theoretical kinetic data generation for tabulated TS models building - Part 1: Application to 1,3-H-shift reactions","authors":"F.C. Destro,&nbsp;R. Fournet,&nbsp;R. Bounaceur,&nbsp;V. Warth,&nbsp;P.A. Glaude,&nbsp;B. Sirjean","doi":"10.1016/j.combustflame.2024.113731","DOIUrl":"10.1016/j.combustflame.2024.113731","url":null,"abstract":"<div><div>Estimation of kinetic parameters is a key aspect of chemical combustion modeling and several approaches were developed to approximate unknown data. In this work, a code in Python was developed to build tables of transition state (TS) models automatically for intramolecular H-shift reactions in alkyl radicals. The code generates the kinetic rules for all the possible combinations of methyl-substituted reactions based on the structures of the minimal, non-substituted, reactant, TS, and product. The code is able to create and differentiate multiple transition state configurations, considering the axial and equatorial positions for the cyclic substituents and including all the possible pathways for the reactions, which is shown to be an important feature in performing accurate automatic kinetic calculations. Each structure is automatically submitted to geometry optimization and electronic energy calculations, as well as the relaxed scans of the torsional modes identified by the code. From the results of electronic calculations, the rate constants for each pathway are obtained automatically by the application of the transition state theory with tunneling corrections, in a defined temperature range. The kinetic coefficients, as well as the modified Arrhenius parameters, are then assembled and organized to create a final table that connects the kinetic data with TS structure characteristics. These tables can be directly applied as a kinetic data source for reaction mechanism development. The ability of the code to generate reliable rate constants was tested for 1,3-H-shift reactions and the results were compared with theoretical data manually produced, and showed a good agreement. In particular, the code was able to create all the transition state configurations, with an exhaustive description of all possible reaction pathways, using a rigorous and systematic counting based on symmetry, stereocenters, and diastereomers. The proposed method leads to more accurate results on these aspects, compared to repetitive hand calculations of dozens of rate constants.</div></div>","PeriodicalId":280,"journal":{"name":"Combustion and Flame","volume":"270 ","pages":"Article 113731"},"PeriodicalIF":5.8,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Turbulent spray combustion modeling in reduced tabulation parameter space by similarity mapping","authors":"Qun Hu,&nbsp;Lipo Wang","doi":"10.1016/j.combustflame.2024.113749","DOIUrl":"10.1016/j.combustflame.2024.113749","url":null,"abstract":"<div><div>To overcome the modeling challenge from the coupling between liquid vaporization and chemical reaction in turbulent spray combustion, a similarity mapping approach is implemented to reduce the flamelet tabulation parameters. In the framework of Eulerian–Lagrangian multiphase large eddy simulations (LES), such a modeling idea is developed upon the conventional flamelet/progress variable model. The flamelet library is constructed from a series of quasi one-dimensional spray counterflow solutions, integrated with the multiple solution modes. Test cases, including the laminar spray counterflow flame and Sydney turbulent spray flame, indicate that this newly proposed model is in principle favorable to improve the numerical predictability with acceptable computational cost. Overall, the flame structure can be appropriately captured, showing better performance compared with some reported results.</div></div><div><h3>Novelty and significance statement</h3><div>A newly proposed similarity mapping spray flamelet/progress variable (SMFPV) model is implemented for turbulent spray combustion. In SMFPV, the number of entry parameters of the flamelet library is reasonably reduced and two-way coupling between flame and evaporation can be realized. Thus in principle, SMFPV is favorable to improve the numerical predictability with acceptable computational cost. Simulation results of test cases justify the modeling idea.</div></div>","PeriodicalId":280,"journal":{"name":"Combustion and Flame","volume":"270 ","pages":"Article 113749"},"PeriodicalIF":5.8,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of the NO formation characteristics and ammonia-N/coal-N transformation mechanism of ammonia-coal co-combustion in O2/CO2 atmosphere","authors":"Ping Chen ,&nbsp;Huichun Wang ,&nbsp;Longxiang Qiao ,&nbsp;Mingyan Gu ,&nbsp;Kun Luo ,&nbsp;Jianren Fan","doi":"10.1016/j.combustflame.2024.113756","DOIUrl":"10.1016/j.combustflame.2024.113756","url":null,"abstract":"<div><div>Exploring the characteristics of NO formation during ammonia-coal co-combustion is crucial for achieving clean combustion. O₂/CO₂ atmosphere is an effective way to achieve low nitrogen combustion of pulverized coal, but the effect of O₂/CO₂ atmosphere on NO formation characteristics of ammonia-coal co-firing is still unclear. This work used high-temperature furnace experiments to investigate the conversion characteristics of fuel-N in ammonia-coal co-combustion under CO₂ atmosphere and conducted quantum chemistry calculations to investigate the molecular pathways of fuel-N oxidation. The experimental results showed that the higher temperature and oxygen concentration results in earlier occurrence of the peak and completion of NO in ammonia-coal co-combustion. Compared to N₂ atmosphere, CO₂ has an inhibitory effect on NO generation in ammonia-coal co-firing and the degree of CO₂ inhibition on the formation of NO per unit mass gradually decreases with increasing the temperature. The theoretical calculation results showed that CO₂ reduces the energy barrier of the rate determining step for ammonia-N oxidation by about 133.81 kJ/mol, promoting the conversion of ammonia-N to nitrogen oxides. However, CO₂ also has a certain degree of inhibitory effect on the coal-N oxidation, increasing the energy barrier of the rate determining step for NO generation from coal-N oxidation. The kinetic results showed that when the temperature is higher than 1673 K, CO₂ has a more obvious promotion effect on ammonia-N oxidation and inhibition effect on coal-N oxidation, but a more significant inhibitory effect on coal-N oxidation, so that the CO₂ atmosphere can inhibit the generation of nitrogen-containing products in ammonia-coal co-combustion to a certain extent.</div></div>","PeriodicalId":280,"journal":{"name":"Combustion and Flame","volume":"270 ","pages":"Article 113756"},"PeriodicalIF":5.8,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Oxidation of butane-2,3-dione at high pressure: Implications for ketene chemistry","authors":"Xiaoyuan Zhang ,&nbsp;Maxence Lailliau ,&nbsp;Yuyang Li ,&nbsp;Yumeng Zhu ,&nbsp;Zehua Feng ,&nbsp;Wei Li ,&nbsp;Philippe Dagaut","doi":"10.1016/j.combustflame.2024.113753","DOIUrl":"10.1016/j.combustflame.2024.113753","url":null,"abstract":"<div><div>Ketene (CH₂CO) mechanism is a building block for developing combustion kinetic models of practical fuels. To revisit the combustion chemistry related to ketene, oxidation experiments of butane-2,3‑dione (diacetyl, CH₃COCOCH₃), considered as an effective precursor of CH₂CO, are conducted in a jet-stirred reactor (JSR) at 10 bar and temperatures ranging from 650 to 1160 K. Identification and quantification of intermediates are achieved by Fourier transform infrared spectrometry, gas chromatography, and mass spectrometry. A kinetic model of diacetyl is constructed based on recent theoretical and modeling studies on diacetyl and ketene, which has been validated against the present data and experimental data of diacetyl and CH₂CO in literature. Generally, the present model can adequately predict most of them, and better predict the methyl-related intermediates under wide pyrolysis and combustion conditions than previous models. Based on modeling analyses, the unimolecular decomposition reaction of diacetyl is the dominant reaction pathway for fuel consumption under different equivalence ratio conditions, especially at high temperatures. Under lean conditions, both the H-atom abstraction reactions by methyl (i.e. CH₃COCOCH₃ + CH₃ = CH₄ + CH₂CO + CH₃CO, R3) and by OH (i.e. CH₃COCOCH₃ + OH = H₂O + CH₂CO + CH₃CO, R5) are important for diacetyl consumption, while under rich conditions R5 becomes negligible. As the most important intermediates in diacetyl oxidation, the main consumption pathways of CH₂CO and CH₃ are dependent on the equivalence ratio conditions. Under lean conditions, CH₂CO mainly reacts with OH to produce CH₂OH and CO (i.e. CH₂CO + OH = CH₂OH + CO, R10), while methyl reacts with HO₂ to produce CH₃O and OH (i.e. CH₃ + HO₂ = CH₃O + OH, R20). In contrast, under rich conditions, the addition-elimination reaction between CH₂CO and H becomes competitive with R10, while the CH₃ self-combination producing C₂H₆ plays a more important role than the CH₃ oxidation pathway R20. Sensitivity analysis of CH₂CO shows that not only the reactions of CH₂CO, but also those of CH₃ are sensitive to CH₂CO formation. This is because CH₃ related reactions influence the distribution of radical pool, which determines the oxidation reactivity of the reaction system.</div></div>","PeriodicalId":280,"journal":{"name":"Combustion and Flame","volume":"270 ","pages":"Article 113753"},"PeriodicalIF":5.8,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142327801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical investigation of lean methane flame response to NRP discharges actuation","authors":"N. Barléon ,&nbsp;D.A. Lacoste ,&nbsp;A.M. Alkhalifa ,&nbsp;O. Vermorel ,&nbsp;B. Cuenot","doi":"10.1016/j.combustflame.2024.113745","DOIUrl":"10.1016/j.combustflame.2024.113745","url":null,"abstract":"<div><div>This study investigates the response of a laminar methane-air flame to Nanosecond Repetitively Pulsed (NRP) discharges in a canonical wall-stabilized burner using a combined experimental and numerical approach. The flow and flame behaviors were modeled using Direct Numerical Simulation (DNS) with an Analytically Reduced Chemistry for a precise chemical description. A phenomenological model incorporating detailed plasma kinetics and experimental observations was developed to simulate plasma effects. Zero-dimensional plasma reactor simulations were used to build up a reduced-order model describing discharge energy distribution in the specific conditions studied. Experimental measurements of electrical profiles identified two discharge regimes: a low-energy Corona discharge and a higher-energy Glow discharge, characterized by distinct spatial energy distributions. Experimental flame response analysis revealed three major phases: marginal response up to 100 pulses, a downstream shift of the flame tip, and stabilization after 400 pulses. Numerical simulations indicated that the Corona regime is crucial for explaining initial flame responses, while the Glow regime influences later stages. Adjustments in the Vibrational–Translational (VT) energy relaxation time and energy deposition ratios between fresh and burnt gases were necessary to match experimental observations. Additionally, an accurate modeling of the transient and steady-state flame responses requires integrating both the specificity of the Corona and the Glow discharge regimes. Future work should focus on measuring or theoretically calculating N₂(v) relaxation times in CH₄-H₂O-CO₂ mixtures and analyzing the spatial energy distribution of discharges interacting with flames to enhance plasma-combustion coupled models.</div><div><strong>Novelty and significance</strong></div><div>In this work, a phenomenological plasma-assisted combustion model has been developed, to investigate a laminar premixed stagnation plate burner, focusing on VT energy relaxation time and spatio-temporal energy distribution modeling. For the first time, not only O₂, N₂ and O but also the fuel and combustion intermediates and products have been considered in the VT relaxation model. It revealed their strong influence on the overall flame response in a case where the discharge crosses a flame front, highlighting the strong beneficial effect of energy deposited in vibrational form. The study questions and investigates the energy distribution from fresh to burnt gases, challenging the conventional uniform energy distribution assumption. The experimental identification of two specific plasma regimes was necessary to predict the transient flame response. Additionally, energy deposited downstream of the flame, in fresh gases, was found to more efficient than in hot gases to enhance combustion.</div></div>","PeriodicalId":280,"journal":{"name":"Combustion and Flame","volume":"270 ","pages":"Article 113745"},"PeriodicalIF":5.8,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142327735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical study on the pretreatment of ammonia by nanosecond pulsed discharge for combustion enhancement: Effects of pretreatment uniformity","authors":"Juntao Ao,&nbsp;Chengdong Kong,&nbsp;Yu Wang,&nbsp;Xiaojiang Wu,&nbsp;Zhongxiao Zhang","doi":"10.1016/j.combustflame.2024.113752","DOIUrl":"10.1016/j.combustflame.2024.113752","url":null,"abstract":"<div><div>The nanosecond (NS) pulsed discharge for ammonia combustion assistance is numerically investigated with a special focus on the effects of discharge pretreatment uniformity. A method to mimic spatially non-uniform discharge pretreatment is established. Using NH₃/O₂/He and NH₃/O₂/N₂ mixtures as examples, the ignition delay time (IDT), the laminar burning velocity (LBV), and the extinction strain rate (ESR) of mixtures pretreated by different discharge pretreatment methods were analyzed under a wide range of pretreatment uniformity. The results indicate that for the premixed NH₃/O₂/He (or N₂) pretreated by NS discharge pulses, with the increase of the pretreatment non-uniformity, the IDT initially increases slightly, reaching a maximum and then decreases rapidly by 80 %, while the LBV and the ESR first decreases slowly, reaching a minimum and then increases rapidly by 10 %. The initial increment of IDT with the non-uniformity can be attributed to the deterioration of discharge-induced chemical effect but the rapid decrease of IDT as the discharge pretreatment becomes highly non-uniform is largely determined by the combustion-related chemical effect. The effects of pretreatment uniformity on LBV and ESR can be largely due to the thermal effect. When the oxidant is pretreated by the NS discharge, the minimal IDT, the maximal LBV and ESR can be observed under uniform conditions owing to the chemical effects and thus a uniform discharge pretreatment is preferred. Furthermore, a comparative analysis of the three pretreatment methods under identical energy input reveals that under uniform pretreatment, the direct pretreatment of pure NH₃ is optimal, since it can generate more H₂ to enhance the combustion. However, under highly non-uniform conditions, the discharge pretreatment of premixed fuel/oxidant mixtures is the most efficient for combustion enhancement.</div></div>","PeriodicalId":280,"journal":{"name":"Combustion and Flame","volume":"270 ","pages":"Article 113752"},"PeriodicalIF":5.8,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ignition and combustion characteristics of boron particles under reduced pressure","authors":"Ying Feng ,&nbsp;Yong Tang ,&nbsp;Dingjiang Xie ,&nbsp;Wei Dong ,&nbsp;Majie Zhao ,&nbsp;Zhiwen Wu ,&nbsp;Baolu Shi","doi":"10.1016/j.combustflame.2024.113733","DOIUrl":"10.1016/j.combustflame.2024.113733","url":null,"abstract":"<div><div>The ignition and combustion processes of boron particles are crucial to achieving high combustion efficiency in solid-fuel ramjet engines, particularly under reduced static pressure conditions in the secondary combustion chamber. This study carried out ignition and combustion experiments on amorphous boron particles with an average size of ∼3 µm, using a Hencken multi-diffusion flat flame burner under controlled pressures (0.3–1 atm) and temperatures (1900–2200 K). Optical measurements were utilized to qualify the ignition time, which increases with decreasing pressure. Then, the ignition and combustion models of small-size boron particles under reduced pressure were established, for which the Langmuir layer was introduced to calculate heat and mass transfer between particles and surrounding gases in the transition regime. Results showed that the Langmuir layer significantly lowered heat transfer rate, increasing the ignition time. A comparison of the heat fluxes of evaporation, heterogeneous reaction, and heat convection for the ∼3 µm boron particle demonstrated that the ignition process was limited by heat convection, while the combustion process is dominated by the heterogeneous reaction near the particle surface.</div></div>","PeriodicalId":280,"journal":{"name":"Combustion and Flame","volume":"270 ","pages":"Article 113733"},"PeriodicalIF":5.8,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}