Applications in Energy and Combustion Science最新文献

{"title":"Soot modeling with temperature- and size-based collision efficiency for nucleation and condensation","authors":"Pavan Prakash Duvvuri ,&nbsp;Michael E. Mueller ,&nbsp;Agnes Jocher","doi":"10.1016/j.jaecs.2025.100407","DOIUrl":"10.1016/j.jaecs.2025.100407","url":null,"abstract":"<div><div>Temperature- and size-based collision efficiencies for the collision of dimerizing gas-phase species and for the condensation of dimers onto soot particles were estimated based on theoretical principles. These collision efficiencies were then implemented within a detailed soot model with the Hybrid Method of Moments (HMOM). For the size dependence, taking advantage of the inherent ability of HMOM to demarcate nucleation and aggregation modes of the soot size distribution, a different condensation collision efficiency is used for each mode to account for the substantial differences in size between the two modes and the effect on condensation collision efficiency. Simulations were performed using detailed chemistry for laminar ethylene flames and were validated for premixed atmospheric, premixed pressurized, and coflow atmospheric diffusion flames. Compared to the base model with constant collision efficiency for a given dimerizing species and 100% collision efficiency for condensation, the proposed model results in a change in the budget of nucleation and condensation rates with increased nucleation and decreased condensation. This change was found to increase the surface growth rate due to an increase in the number of primary particles resulting from increased nucleation/reduced condensation and the corresponding increase in soot surface area. This change was found to improve the prediction of soot volume fraction significantly for growth-dominated flames. For the coflow diffusion flame in particular, the maximum soot volume fraction shifted from the centerline to the wings of the flame, consistent with experimental measurements, in stark contrast to the base model with limited soot in the wings of the flame.</div></div>","PeriodicalId":100104,"journal":{"name":"Applications in Energy and Combustion Science","volume":"24 ","pages":"Article 100407"},"PeriodicalIF":5.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145266087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A reduced kinetic mechanism for ammonia/hydrogen mixtures with alleviated stiffness and high accuracy tailored for high-fidelity numerical simulations","authors":"Wei Guan ,&nbsp;Cheng Chi ,&nbsp;András György Szanthoffer ,&nbsp;Dominique Thévenin","doi":"10.1016/j.jaecs.2025.100377","DOIUrl":"10.1016/j.jaecs.2025.100377","url":null,"abstract":"<div><div>Co-firing ammonia with hydrogen is recognized as a promising energy strategy for achieving a carbon-neutral and sustainable future. It offers potential advantages over the combustion of pure hydrogen/air or pure ammonia/air individually in practical applications. High-fidelity simulations, such as Direct Numerical Simulations and Large-Eddy Simulations are essential for a better understanding of ammonia/hydrogen flames. Such simulations require the availability of an affordable but accurate kinetic mechanism with alleviated stiffness. In this study, a reduced kinetic mechanism comprising 17 transported species, 10 quasi-steady-state species, and 180 reactions was developed, derived from a comprehensive mechanism (the NUIG-2023 mechanism with 39 species and 306 reactions) while maintaining high accuracy across a wide range of validation cases. The reduced mechanism was extensively compared with the original one and with experimental datasets for predictions of ignition delay times, laminar flame speeds, species mole fraction profiles, and S-curves. Moreover, the obtained integrated fuel consumption rates and species profiles of NO, NO₂, and N₂O were compared for hydrogen-ammonia stratification. The analysis has been repeated for a variety of ammonia/hydrogen mixtures. As a result, the reduced mechanism demonstrated excellent capability to accurately replicate the fundamental combustion characteristics of ammonia/hydrogen flames for a wide range of conditions. The calculation time using the reduced mechanism in the simulations of stratified flame with an explicit time integration is approximately 5.5 times faster than that of the full NUIG-2023 mechanism, which requires additionally an implicit scheme to handle chemical stiffness. This work paves the way for future investigations of NH₃/H₂ flames by DNS and LES in practically relevant configurations.</div></div>","PeriodicalId":100104,"journal":{"name":"Applications in Energy and Combustion Science","volume":"24 ","pages":"Article 100377"},"PeriodicalIF":5.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145010762","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-hole liquid ammonia spray collapsing behaviors: Morphologies, collapsing time, and region diagram","authors":"Xiaoxin Yao,&nbsp;Gangwei Zeng,&nbsp;Xiao Liu,&nbsp;Zuohua Huang,&nbsp;Chenglong Tang","doi":"10.1016/j.jaecs.2025.100379","DOIUrl":"10.1016/j.jaecs.2025.100379","url":null,"abstract":"<div><div>The flash-boiling and collapsing behavior of low-boiling-point liquid ammonia multi-hole spray can influence the efficient application of liquid ammonia on internal combustion engines. In order to investigate the mechanism and boundary conditions for liquid ammonia multi-hole spray to collapse, the macroscopic morphology and liquid cross-sectional distribution of liquid ammonia multi-hole spray under different ambient temperatures and pressures are recorded by schlieren high-speed photography and laser sheet Mie-scattering method, and the changes of several spray characteristic parameters such as spray tip penetration, spray angle, and cross-sectional area are obtained. Three different spray collapsing modes are defined: early collapsing, late collapsing, and non-collapsing. The increase of collapsing degree caused by the rise of ambient temperature and the decrease of ambient pressure results in earlier plume merging, accelerated penetration, and a reduced spray cross-sectional area. The time point of spray accelerating penetration, which is gradually advanced with the increase of spray collapsing degree, is defined as collapsing time, and an empirical correlation is proposed to predict the collapsing time under different ambient conditions. Based on the experimental phenomenon, the different spray collapsing modes and behaviors under different ambient conditions are summarized and analyzed, and the transition of spray collapsing mode under different ambient temperatures and pressures is shown by a region diagram.</div></div>","PeriodicalId":100104,"journal":{"name":"Applications in Energy and Combustion Science","volume":"24 ","pages":"Article 100379"},"PeriodicalIF":5.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145010763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biohydrogen, a potential roadmap to sustainable green energy supply and carbon sequestrating in the transport sector by 2060","authors":"Aqib Zahoor ,&nbsp;Nadeem Tahir ,&nbsp;Lingyu Tai ,&nbsp;Wenchao Ma ,&nbsp;Mingtao Hu ,&nbsp;Yajuan Yu ,&nbsp;Amanda Reichelt-Brushett ,&nbsp;Tapas Sen ,&nbsp;Martina Damizia ,&nbsp;Benedetta de Caprariis ,&nbsp;Paolo De Filippis","doi":"10.1016/j.jaecs.2025.100410","DOIUrl":"10.1016/j.jaecs.2025.100410","url":null,"abstract":"<div><div>Current research goals lead to achieve zero carbon emission in transportation, agricultural, and forest sector through biohydrogen production by biomass residues. To assess the current development status and forecast future technologies, Traffic emission evaluation model of project (TEEMP) was used. Results show that, in 2024 cumulative CO₂ emission by forest and agricultural were 3.5 billion metric tonne (BMt) while from transportation 8.47 BMt. Major assessments indicate that globally about 5–10 Gt/year of biomass residues are technically and economically recoverable, mainly from China, India, the U.S., Russia, and Europe, corresponding to roughly 40–60 EJ/year of bioenergy potential. Instead of burning these wastes in fields, they should be collected, converted into biohydrogen, and used as a fossil fuel replacement to reduce CO₂ emissions. So far, biological pre-treatment and dark-photo fermentation are well-known techniques for the production of high-quality biohydrogen due to their controllability and low energy consumption. The experimental findings showed that the collection of agricultural 1840 Mt and forest 927 Mt waste residues can produce 15,460 Kt and 929 Kt of biohydrogen respectively, which will help to achieve to reduce the carbon emission of 85.13 Mt agriculture and 57.75 Mt forest by 2040 respectively. Sustainable biohydrogen production can be achieved by enhancing the production capacity by solving collection, transportation, and management challenges. These challenges can be overcome through the development of policies, implementations, laws, government and organization training, satellite monitoring, and electronic media. Lastly, bottom-up accounting framework scenario reflected the overall possibilities of CO₂ emissions reduction from 9.699 BMt to 0.03 BMt by 2010 to 2060 can be reduced from the atmosphere by stopping the open field burning of waste residues and using biohydrogen as an alternative to fossil.</div></div>","PeriodicalId":100104,"journal":{"name":"Applications in Energy and Combustion Science","volume":"24 ","pages":"Article 100410"},"PeriodicalIF":5.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145323711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a high-insulation and rapid-response dry powder agent for suppressing fires in lithium-ion batteries","authors":"Yingxin Wu ,&nbsp;Ziye Ling ,&nbsp;Zhengguo Zhang ,&nbsp;Xiaoming Fang ,&nbsp;Shuping Wang","doi":"10.1016/j.jaecs.2025.100384","DOIUrl":"10.1016/j.jaecs.2025.100384","url":null,"abstract":"<div><div>To address the insufficient heat absorption and limited cooling performance of conventional ABC dry powder below 300 °C, a novel PA dry powder extinguishing agent with low decomposition temperature and high enthalpy was developed. The material releases 1367 J/g of decomposition enthalpy within 100–180 °C, providing a 96.9 % increase in heat absorption below 300 °C compared with ABC dry powder, thereby effectively matching the early exothermic stage of lithium-ion battery thermal runaway. In fire tests with 51 Ah ternary lithium-ion batteries, uncontrolled combustion lasted 149 s, whereas extinction times were reduced to 10 s with ABC dry powder and 11 s with PA dry powder, shortening burning duration by over 92 % and rapidly suppressing jet flames. Temperature measurements further revealed that PA dry powder reduced the safety valve temperature to 140 °C, markedly lower than 266 °C for ABC dry powder, and the peak temperature after spraying was only 283.3 °C, 165.9 °C lower than that of ABC dry powder. Overall, PA dry powder exhibits both rapid fire suppression and superior cooling capacity, significantly delaying thermal runaway and showing strong application potential.</div></div>","PeriodicalId":100104,"journal":{"name":"Applications in Energy and Combustion Science","volume":"24 ","pages":"Article 100384"},"PeriodicalIF":5.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145049497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Single-snapshot-based dynamical mode prediction of a flickering flame via a Fourier-neural-operator network","authors":"Xi Xia ,&nbsp;Junhao Deng ,&nbsp;Tao Yang ,&nbsp;Liangliang Xu ,&nbsp;Amir Mardani ,&nbsp;Peng Zhang ,&nbsp;Dan Zhao","doi":"10.1016/j.jaecs.2025.100380","DOIUrl":"10.1016/j.jaecs.2025.100380","url":null,"abstract":"<div><div>The self-excited flickering of jet diffusion flames is dominated by the dynamics of periodic coherent vortical structures, which can typically be analyzed through dynamic mode decomposition (DMD) based on a time-resolved flow-field sequence. We present a neural network that extracts these structures and their energy content instantaneously from a single snapshot of the vorticity field, by leveraging a Fourier neural operator (FNO) combined with a DMD-based output layer that enforces physical interpretability. Trained on direct numerical simulation (DNS) data of different jet flames, the network predication shows good agreement with the classical DMD in capturing the wavelength and pattern of the coherent structures for the three leading instantaneous DMD modes. In reconstructing the vorticity field, the prediction exhibits only about 2% normalized error compared with the original DNS data, preserving the vortex-core trajectory and intensity with normalized errors of approximately 2% and 7%, respectively. These demonstrate the proposed network to be an effective yet lightweight surrogate for dynamic modal analysis of unsteady flames, especially in applications where the system is observable only at limited times.</div></div>","PeriodicalId":100104,"journal":{"name":"Applications in Energy and Combustion Science","volume":"24 ","pages":"Article 100380"},"PeriodicalIF":5.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145049498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optical diagnostics-based numerical modeling of a compression-ignition optical research engine implementing ducted fuel injection","authors":"C. Segatori ,&nbsp;M. Orlando ,&nbsp;A. Piano ,&nbsp;F. Millo ,&nbsp;C.J. Mueller","doi":"10.1016/j.jaecs.2025.100408","DOIUrl":"10.1016/j.jaecs.2025.100408","url":null,"abstract":"<div><div>Ducted fuel injection (DFI) is a promising strategy to dramatically reduce engine-out soot emissions from compression-ignition (CI) engines. To accelerate the integration of DFI into real-world engines, computational fluid dynamics (CFD) is a powerful tool for its understanding and optimization. Although CFD has been largely adopted for investigating DFI in CI engines, accuracy and reliability of the numerical outcomes remain often questionable.</div><div>Therefore, this article proposes a step forward in the CFD model development and validation process of a CI optical engine implementing DFI, considering both global and local perspectives. Indeed, leveraging the optical diagnostics dataset, the correct reproduction of the combustion and emissions formation processes – across a range of loads and oxygen levels for both CDC and DFI configurations – was tested not only in terms of typical aggregated values (i.e., pressure, burn rate, engine-out emissions) but also locally in terms of lift-off length, flame evolution, and soot natural luminosity (NL). For the latter a proper methodology was used to virtually replicate soot NL distribution starting from the CFD variables. Despite the complexity of this luminosity-based comparison, the model was found to reasonably replicate the main trends, for both CDC and DFI, thus highlighting predictive capability, not only in terms of engine-out soot emission values, but also of the in-cylinder soot formation/oxidation processes. Moreover, the present results demonstrate the robustness of the methodology to compute a virtual NL from CFD outputs, which could be of interest to thoroughly validate combustion models every time soot prediction accuracy plays an important role.</div></div>","PeriodicalId":100104,"journal":{"name":"Applications in Energy and Combustion Science","volume":"24 ","pages":"Article 100408"},"PeriodicalIF":5.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145323709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Transcritical real-fluid effects on dual-fuel combustion of methane and n-dodecane","authors":"Mohamad Fathi,&nbsp;Dirk Roekaerts,&nbsp;Stefan Hickel","doi":"10.1016/j.jaecs.2025.100398","DOIUrl":"10.1016/j.jaecs.2025.100398","url":null,"abstract":"<div><div>A comprehensive set of accurate physical models and numerical simulation methods for transcritical dual fuel combustion systems is presented. The method combines multiphase real-fluid physical properties modeling, flamelet-based chemistry reduction, and large-eddy simulation (LES). It allows a fully integrated simulation of the multiphase region and the combustion zones in the turbulent flames. A central challenge in dual-fuel combustion applications is the successful ignition of low-reactivity ambient fuel by the high-reactivity pilot fuel jet. The interaction of the radical pools associated with both fuels is known to be an important characteristic. This study captures the evolution of this interaction across both the low-temperature combustion (LTC) and high-temperature combustion (HTC) regimes. Three cases are investigated, each involving the injection of an n-dodecane jet into a 6<!--> <!-->MPa, 1000<!--> <!-->K ambient. The cases differ only in ambient composition: (1) a single-fuel (SF) baseline case with a mixture of air and combustion products, and two dual-fuel (DF) cases with methane and a 90:10 (by volume) methane/ethane blend added to the ambient. Insights on ignition and flame structure are gained from homogeneous reactor simulations, transcritical counterflow diffusion flames, and LES. Combustion modes are defined by threshold levels of key species and temperature. The flame volume is subdivided according to the modes and for each mode the ignition delay and the temporal evolution of heat release rate (HRR) are obtained. The differences in the radical pools of SF and DF combustion are demonstrated. LTC ignition is shown to start in the multiphase region near the base of the jet. The high accuracy of the proposed methods provides a firm basis for modeling prospective dual-fuel systems using alternative fuels.</div></div>","PeriodicalId":100104,"journal":{"name":"Applications in Energy and Combustion Science","volume":"24 ","pages":"Article 100398"},"PeriodicalIF":5.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145323713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reconstruction of heat release rate in one-dimensional counterflow flames","authors":"Tao Yang ,&nbsp;Jie Niu ,&nbsp;Xuren Zhu ,&nbsp;Yujing Wei ,&nbsp;Gani Issayev ,&nbsp;Peng Zhang","doi":"10.1016/j.jaecs.2025.100427","DOIUrl":"10.1016/j.jaecs.2025.100427","url":null,"abstract":"<div><div>The heat release rate (HRR) is a fundamental parameter in combustion science and technology, critical for both performance monitoring and device optimization. However, its direct experimental determination remains challenging, even for well-defined one-dimensional (1-D) laminar flames. This study develops a computationally efficient method, termed the Fast Temperature-based HRR Prediction (FT-HRRP), to accurately reconstruct HRR profiles in 1-D counterflow flames using solely temperature data, derived through rigorous analysis of the energy equation. A comprehensive validation database was established by using flame simulations of hydrogen-ammonia fuel mixtures with both non-premixed and premixed configurations, systematically examining the method's robustness across various strain rates (40–300 <span><math><mover><mi>s</mi><mo>¯</mo></mover></math></span>), ammonia blending ratios (0–80 %), and equivalence ratios (0.8–1.2 for premixed cases). The reconstructed HRR profiles show excellent agreement with reference calculations, capturing all essential characteristics, including profile shapes, peak locations, and half widths of profiles. The accuracy and robustness have been confirmed by the experimental data from a published paper. Incorporating the additional physics of species mass transfer of key components (H₂, NH₃, O₂, N₂, etc.) in the present method, some subtle albeit nonessential features of HRR profiles can be well reproduced. The proposed method has the potential of being a useful and efficient analysis tool for 1-D counterflow flames.</div></div>","PeriodicalId":100104,"journal":{"name":"Applications in Energy and Combustion Science","volume":"24 ","pages":"Article 100427"},"PeriodicalIF":5.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145624092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment and ranking of 16 binarization methods for turbulent swirl flame images of various flame types","authors":"Réka Anna Kardos,&nbsp;Gyöngyvér Tóthpálné Hidegh,&nbsp;Erika Rácz,&nbsp;Viktor Józsa","doi":"10.1016/j.jaecs.2025.100428","DOIUrl":"10.1016/j.jaecs.2025.100428","url":null,"abstract":"<div><div>Commercial digital cameras are versatile and low-cost non-invasive diagnostic tools for flame imaging with easy implementation for both industrial and laboratory flames. To quantify various flame metrics, flame image binarization is the first critical step in processing. Therefore, it is essential to know which binarization techniques perform well on different flame types, encompassing various operating conditions. This paper evaluates sixteen binarization methods for processing the chemiluminescent emission of eight natural gas and diesel oil flames captured by a commercial digital camera using three spectral filters at central wavelengths of 430, 515, and 590 nm. Proper binarization is challenging due to the blurry edges of the flame, which result from its finite thickness. If online data is required, processing time becomes critical, which is the first basis of the performance assessment of the sixteen binarization techniques. The second basis is a novel method for checking consistency, indicating the sensitivity of pixel assignment to foreground or background in a similar, yet new intensity neighborhood, which is critical for turbulent flames. The third metric was accuracy. It was defined as the fraction of the flame edge obtained from the binary image that was contained in the boundary region, determined based on the local standard deviations to avoid all biases associated with the use of a ground truth, making this basis novel and robust. The results were summarized for four different flame categories, concluding, for example, that the widely used Otsu method performs well in all cases.</div></div>","PeriodicalId":100104,"journal":{"name":"Applications in Energy and Combustion Science","volume":"24 ","pages":"Article 100428"},"PeriodicalIF":5.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145624131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}