Flow, Turbulence and Combustion最新文献

{"title":"Interaction of Detonations with Supersonic Obstacles","authors":"Ashwath Sethu Venkataraman,&nbsp;Elaine S. Oran","doi":"10.1007/s10494-026-00757-9","DOIUrl":"10.1007/s10494-026-00757-9","url":null,"abstract":"<div><p>The motion of a driven obstacle moving at supersonic speeds in a reactant mixture leads to a complex flow field consisting of shocks and turbulent flow structures with non-uniform reactant distribution. The interaction of the strongest form of a reaction wave, a detonation, with such a flow field begins with detonation-shock interactions, and is followed sequentially by complex shock reflections, detonation diffraction, and detonation-turbulence interactions. The boundary and initial conditions at the end of each interaction sets the stage for the next interaction. The purpose of this paper is to understand how the detonation wave is affected by this interaction. A parametric study is performed to study the effects of chemical heat release, obstacle size, and speed on the detonation dynamics. First, we compared the interaction of a detonation and a non-reacting shock with the moving obstacle. We found that the non-reacting shock was affected over a longer distance on interacting with the obstacle. Then, we varied the obstacle height and speed to understand how it affects the intrinsic cellular structure of the detonation wave. We found that the detonation fully quenched due to diffraction when the obstacle height was larger than the detonation cell size for a given obstacle speed. An analysis of the detonation wave based on the Damköhler number characterizes how the detonation dynamics are affected by the interaction when the obstacle speed is varied for a fixed obstacle height. We found that the interaction has the overall effect of reducing the Damköhler number at the detonation front. The distribution of reactants and the local flow field surrounding the obstacle have a major influence on the detonation dynamics.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"116 4","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10494-026-00757-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147938150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Comparison between Localized Skin-Friction Reduction and Suction on a Supercritical Airfoil","authors":"Annika Frede,&nbsp;Giulio Soldati,&nbsp;Sergio Pirozzoli,&nbsp;Niccolò Berizzi,&nbsp;Maurizio Quadrio,&nbsp;Davide Gatti","doi":"10.1007/s10494-026-00748-w","DOIUrl":"10.1007/s10494-026-00748-w","url":null,"abstract":"<div><p>In this work, direct numerical simulations are used to investigate which physical effects of active flow control are most relevant for improving the aerodynamic performance of airfoils. To this end, two active flow control strategies based on inherently different physical mechanisms are systematically compared on the upper surface of the supercritical V2C airfoil in compressible transonic flow. The first strategy consists of streamwise-travelling waves of spanwise wall velocity (StTW), a skin-friction drag reduction technique that locally decreases wall shear stress in the region of application. The second strategy is uniform wall-normal suction, which locally increases skin-friction drag. One strength of the present study is that the control configurations are evaluated at matched lift coefficients to isolate the impact of the control mechanisms on drag components, boundary-layer development, shock position, and energetic cost. Despite their opposite local effects on skin-friction drag, both control strategies yield comparable and significant improvements in global aerodynamic efficiency. The analysis reveals that, for both approaches, the dominant mechanism responsible for the efficiency increase is a downstream displacement of the shock, accompanied by a reduction in boundary-layer momentum thickness. These results highlight the central role of shock–boundary-layer interaction control in enhancing transonic aerodynamic performance and demonstrate that skin-friction drag reduction alone is not a sufficient metric for assessing the effectiveness of active flow control strategies.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"116 4","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10494-026-00748-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147938149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Thermodynamic Analysis for Carbon Nanotube Growth Mechanism in Combustion-Based Environment","authors":"Muhammad Thalhah Zainal,&nbsp;Norikhwan Hamzah,&nbsp;Tarit Das,&nbsp;Abiodun Abdulhameed Amusa,&nbsp;Mohd Fairus Mohd Yasin","doi":"10.1007/s10494-026-00756-w","DOIUrl":"10.1007/s10494-026-00756-w","url":null,"abstract":"<div><p>Comprehending the favourable conditions for CNT growth in flames requires a thermodynamic analysis based on an integrated framework that comprises a coupled computation of flame-scale and kinetic-based particle-scale models. However, the lack of such investigations hampers a deeper understanding of the CNT growth mechanism in a heterogeneous flame environment. In the present study, a coupled computation of computational fluid dynamics (CFD) and a kinetic-based growth rate model was performed for an inverse diffusion flame fuelled by a 30% methane − 5% ethylene mixture. Flame parameters (temperature and combustion species) and CNT growth rate were resolved by CFD and the growth rate model, respectively, and were further related within a thermodynamic framework through Arrhenius and Van’t Hoff plots. Additionally, combustion reactions comprising of three carbon monoxide (CO) - based reactions and five hydrocarbon (C<span>(_m)</span>H<span>(_n)</span>) - based reactions were analysed using Gibbs free energy plots to identify the favourable dissociation reactions for CNT growth. Arrhenius plots at locations 8, 13, and 18 mm downstream of the burner exhibit Arrhenius behaviour in the low temperature range (700–850 K) and anti - Arrhenius behavior in the high temperature regime (850–1000 K). This observation of a mixed Arrhenius and anti - Arrhenius behaviour provides a unified explanation for both CNT growth and catalyst deactivation, corresponding respectively to the lower and higher temperature regions of the flame. Based on the Arrhenius plots, the activation energy for CNT growth in the present work is determined to be 40–50 kJ/mol, providing the first quantitative estimate of CNT growth activation energy for flame - based synthesis. Thermodynamic analysis based on Arrhenius and Van’t Hoff plots suggests that CNT growth driven by the production of methane is more favourable than that through the production of carbon monoxide. The analysis is extended to Gibbs free energy plots, which indicate that hydrocarbon in particular methane-based dissociation reactions are highly favourable pathways for CNT growth in flames. Although the same analysis also supports CO-based dissociation reactions as favourable, the relatively lower abundance of CO resulting from the combustion of the present fuel makes the contribution of CO to CNT growth secondary compared to methane.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"116 4","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10494-026-00756-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147938148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Investigation of Hypersonic Boundary-Layer Transition on a Typical Re-Entry Vehicle: Insights into Spot-like, Non-Modal Breakdown Mechanisms","authors":"Dibya Kanti Golui,&nbsp;S. L. N. Desikan","doi":"10.1007/s10494-026-00751-1","DOIUrl":"10.1007/s10494-026-00751-1","url":null,"abstract":"<div>\u0000 \u0000 <p>The onset of boundary-layer transition on the windward side of a typical re-entry vehicle, fixed at its hypersonic trim angle of attack of 40⁰, has been experimentally investigated. The study is conducted in a combustion-driven shock tunnel, tailored at a stagnation enthalpy of 2.4 MJ/kg and a freestream Mach number of 8. Transition is characterized using time-resolved surface heat-flux measurements, which provide a sensitive indicator of laminar-turbulent breakdown in hypersonic flows. Experiments are performed over a wide range of unit Reynolds numbers from 1.48 × 10⁶ to 5.34 × 10⁶ m^− 1. At lower Reynolds numbers, the boundary layer exhibits laminar characteristics with asymptotic heat-flux trends. Conversely, at higher Reynolds numbers, intermittent and finite-duration disturbances consistent with turbulent-spot-like breakdown events appear in the transient heat flux traces. These are observed to convect, grow, and merge downstream, producing elevated heating with broadband temporal fluctuations characteristic of turbulence. Furthermore, with increasing Reynolds number, time-averaged heat flux levels rise at downstream stations and the onset of transition progressively shifts upstream, consistent with the Reynolds-number dependence of transitional flows. Finally, the hypothesis of concentrated breakdown, originally formulated for flat plates, is adapted to the present re-entry geometry to reconstruct the heat flux distribution within the transitional boundary layer, demonstrating that spot-based intermittency concepts can be meaningfully incorporated into transition interpretation for hypersonic re-entry configurations featuring mild favourable streamwise pressure gradients. This study thus provides new physical insight into hypersonic boundary-layer transition in non-canonical geometries of practical relevance by offering an experimentally grounded interpretation based on non-modal, stochastic mechanisms.</p>\u0000 </div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"116 4","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147727448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"LES-ADM Accuracy Assessment via An Error-Landscape Approach","authors":"Lena Caban,&nbsp;Artur Tyliszczak,&nbsp;Bernard J. Geurts","doi":"10.1007/s10494-026-00750-2","DOIUrl":"10.1007/s10494-026-00750-2","url":null,"abstract":"<div><p>This paper investigates the accuracy and robustness of the approximate deconvolution method (ADM) in large eddy simulation (LES) using an error-landscape approach. Two canonical turbulence test cases—forced and decaying homogeneous isotropic turbulence (F-HIT / D-HIT)—are analyzed. We assess how user-defined parameters in ADM, including the filter type, its order (<span>(p=2-10)</span>), and the number of deconvolution iterations (<span>(N_textrm{ADM}=0-10)</span>), affect the predictive performance of the model. Finite and compact difference filters are employed for deconvolution. Along with the box and Gaussian filters, these are also used as an LES filter. The resulting errors associated with the use of ADM are compared with LES errors arising from the Smagorinsky model with a model constant in the range <span>(0 &lt; C_Sle0.2)</span> (20 levels), and a no-model approach. The LES results are validated against direct numerical simulation (DNS) data. For the F-HIT case, we focus on the accuracy of the prediction of time-averaged kinetic energy and skewness of the velocity components and their derivatives. In the case of the Smagorinsky model, accurate results are obtained for <span>(C_Sle0.1)</span>, while for ADM <span>(pge6)</span> and <span>(N_textrm{ADM}=2)</span> appear to be required. An exception is the prediction of the velocity-derivative skewness, which, in all cases, differs significantly from the DNS solution due to its strong reliance on small-scale flow features. The classical error-landscape approach is applied for the D-HIT configuration. By performing direct comparisons of key solution properties, this approach enables identifying the parameter range in which ADM attains optimal accuracy leading to results that are more accurate than can be obtained by applying the Smagorinsky model, as well as regions where ADM-based simulations may become unstable or exhibit accuracy levels inferior to the reference no-model case. The latter arises especially on coarse grids when <span>(N_textrm{ADM}geq 2)</span>, or when the LES filter does not sufficiently attenuate the solution at the grid cut-off frequency. From the perspective of simulation stability, the safer choice is to perform deconvolution with a high-order filter, preferably an implicit formulation, which also ensures considerable accuracy. The total analysis encompasses comparisons of over <span>(6000)</span> simulations. It provides valuable guidance for the effective use and future development of stable ADM-based modeling strategies. In this respect, an important finding is that increasing <span>(N_textrm{ADM})</span>, rather than improving deconvolution accuracy, may lead to instability reflecting the ill-posedness of recovering scales that are poorly represented on the chosen simulation grid.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"116 4","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147738139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 Triangle-shaped Protrusions Exposed to High-speed Flow in Rarefied Regime","authors":"Moslem Sabouri,&nbsp;Elyas Lekzian","doi":"10.1007/s10494-026-00741-3","DOIUrl":"10.1007/s10494-026-00741-3","url":null,"abstract":"<div>\u0000 \u0000 <p>This study examines the aerodynamic effects of 2D triangular protrusions on hypersonic flow within transitional regimes using the Direct Simulation Monte Carlo method. Three protrusion geometries-isosceles, backward, and forward-are analyzed. Results indicate that the forward geometry exhibits the highest in-domain pressure and temperature peaks, along with elevated surface pressure, heat transfer coefficients, and boundary layer thickness. The backward configuration shows greater sensitivity of peak temperature to protrusion surface temperature variations, while the forward case demonstrates higher pressure sensitivity. Across all configurations, maximum pressure (<span>(:{C}_{p,:max})</span>) and heat transfer (<span>(:{C}_{h,:max})</span>) coefficients occur on the windward surface, with (<span>(:{C}_{p,:max})</span>) increasing and (<span>(:{C}_{h,:max})</span>) decreasing with rising surface temperatures. For the protrusion height ratio <span>(:{h}_{p}/{h}_{s})</span> of 1.0, the isosceles configuration exhibits almost no vortices both upstream and downstream of the protrusion. However, for height ratios of <span>(:{h}_{p}/{h}_{s})</span>= 1.5 and 2.0, vortex structures are observed near the isosceles, backward, and forward protrusions. The vortex grows with the increase in <span>(:{h}_{p}/{h}_{s})</span>. As the protrusion height ratio increases, the high-temperature region becomes thicker, particularly in the downstream area. As the height ratio increases, both flow and surface peak properties are elevated. Higher Mach numbers significantly reduce the boundary layer thickness. Moreover, Mach number has a pronounced impact on <span>(:{C}_{p,:max})</span>and <span>(:{C}_{h,:max})</span>. The protrusion drag increases with higher protrusion surface temperature, greater protrusion height ratios, and elevated Mach numbers across all configurations. Conversely, drag decreases as the Knudsen number rises.</p>\u0000 </div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"116 3","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147737426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Turbulence and Fuel Properties on Pre-vaporized Jet Flame Surface Statistics","authors":"J. Schihl,&nbsp;A. W. Skiba,&nbsp;C. D. Carter,&nbsp;P. M. Allison","doi":"10.1007/s10494-026-00747-x","DOIUrl":"10.1007/s10494-026-00747-x","url":null,"abstract":"<div>\u0000 \u0000 <p>This research effort presents a detailed and systematic analysis of the impact of turbulence on surface characteristics of premixed flames produced with vaporized liquid fuels. The turbulent Reynolds Number (<i>Re</i>_<i>T</i>) varied between 760 and 4,200, with equivalence ratios of 0.9 and 1.1. Hydroxyl (OH) planar laser-induced fluorescence (PLIF) was employed to mark the flame front. Flame surface density (FSD), average progress variable (<span>(overline{c})</span>), flame-front curvature (<i>κ</i>), fractal dimension (FD), and inner cut-off scale (ε_i) were extracted from those images, which enabled additional analysis, including: turbulent flame area ratio and brush thickness. It was found that increasing the turbulent Karlovitz Number (<i>Ka</i>_<i>T</i>) broadened probability density functions (PDFs) of flame-front curvature, increased FSD across reaction variable space, increased turbulent area ratio and decreased brush thickness. Notably, for lean conditions, all surface statistics converged as <i>Ka</i>_<i>T</i> exceeded 10. Similarly, global consumption speed was analyzed and found to be consistent with previous findings in methane-air mixtures. Analysis of “flamelet” consumption speed shows that despite having different thermochemical properties, all of the flames considered behave similarly at a macroscopic level when properly normalized by a suitable <i>S</i>_<i>L</i>. Lastly, a fractal analysis revealed consistent FD values that approximately equal the theoretical value of 7/3 for these types of flames. Also, such analysis indicated that the normalized inner cut off scales are not sensitive to fuel type and, as in prior studies of gaseous fueled flames, decrease with increasing <i>Ka</i>_<i>T</i>.</p>\u0000 </div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"116 3","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10494-026-00747-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147737674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Large Eddy Simulation Analysis of Turbulence Generated by a Two-Plane Active Grid Using an Optimized Motion Protocol","authors":"Alper Akardere,&nbsp;Aziz Mert Karul,&nbsp;Özgür Ertunç","doi":"10.1007/s10494-026-00744-0","DOIUrl":"10.1007/s10494-026-00744-0","url":null,"abstract":"<div>\u0000 \u0000 <p>Active grid turbulence generators that utilize rotating or flapping winglets can achieve higher turbulence levels in a controlled manner. Most active grid studies are experimental, and active grids in those were designed based on empirical data and calculations based on order-of-magnitude analysis. We used large-eddy simulations (LES) to assess the effects of square and circular winglet shapes and motion protocol. Differences in generated turbulence at distances of up to 5 mesh sizes from the active grid in the flow direction were analyzed in terms of turbulence intensity, Taylor-scale Reynolds number, spectra, isotropy level, and flow homogeneity. For these analyses, a two-plane active grid design was used to prevent full closure during operation in a wind tunnel. The numerical simulation’s validity was assessed using a combination of numerical benchmarks, physical parameters, and experimental validation, thereby facilitating the application of Large Eddy Simulation to the design of active grids. Rather than employing either random or prescribed motion protocols, this study developed an optimization method to determine the transient angular positions of the winglets. The optimization focuses on two objective functions: achieving a specified area-closure intensity and maintaining a target mean Rossby number. Simulations for the square wiglets were conducted at a constant intensity of area closure at two mean Rossby numbers, and one simulation for a circular winglet at the same lowest Rossby number and the same intensity of area closure. Five mesh size downstream of the active-grid, circular winglets generated approximately twice the Taylor-scale Reynolds number (<span>(text{Re}_{lambda}approx 375)</span>) compared to square winglets (<span>(text{Re}_{lambda}approx 180)</span>) at the same mean Rossby number. However, this increase in turbulence level was accompanied by higher levels of anisotropy and inhomogeneity in the turbulent kinetic energy and mean velocity fields. The downstream set of rods was found to be responsible for the higher velocity fluctuations in the lateral direction perpendicular to their rotation axis, both for square and circular grids. The global isotropy level for circular winglets showed a deviation of 25–30% from unity, which is significantly greater than that observed in square winglet configurations. The results revealed a clear trade-off between increasing turbulence level and preserving flow homogeneity and isotropy. Additionally, the implementation of a two-plane active grid system, combined with different winglet geometries and an optimization-based motion protocol, demonstrated significant potential for effectively modulating these flow characteristics.</p>\u0000 </div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"116 3","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10494-026-00744-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147737673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Internal Flow Characteristics and Vortex Evolution of Fuel Injector with Dynamic Needle Oscillation","authors":"Ziman Wang,&nbsp;Tong Liang,&nbsp;Changzhao Jiang","doi":"10.1007/s10494-026-00739-x","DOIUrl":"10.1007/s10494-026-00739-x","url":null,"abstract":"<div><p>To enable efficient and clean combustion in internal combustion engines, precise control over fuel injection and atomization is essential. Dynamic oscillation of the injector needle is a primary factor governing internal flow and atomization performance; however, its underlying mechanisms are substantially more complex than the commonly assumed static eccentricity model, and remain insufficiently understood. This study systematically examines this dynamic phenomenon by analyzing the impact of needle oscillation on the internal flow dynamics and vortex evolution in both single-hole and multi-hole injectors, with particular attention to the critical needle opening and closing stages. The results reveal that dynamic needle oscillation induces reverse-rotating large-scale vortices within the sac, which further interact to form small-scale vortex pairs. In the four-hole injector, flutter consistently suppresses the mass flow rate across all orifices, exhibiting pronounced asymmetry; the orifices located outside the flutter plane experience the strongest reduction, especially at low needle lifts. Moreover, under high-pressure (200 MPa) compressible conditions, the suppressive effect of flutter on mass flow rate becomes more significant, accompanied by intensified flow instability and persistent pressure oscillations. The dynamic mechanisms identified in this work overcome the limitations of conventional static simulations. These findings not only offer new insights for improving injection performance in traditional diesel engines but also provide important theoretical and engineering guidance for the design of injection systems for emerging green fuels such as liquid ammonia, methanol, and biodiesel.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"116 3","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147607383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterizing the Interactions Between Flow Dynamics and Soot Production in Ethylene Non-Premixed Pulsed Flames","authors":"Nicolás Gutiérrez,&nbsp;Nicolás Mancilla,&nbsp;Denisse Saavedra,&nbsp;Amanda García,&nbsp;Gonzalo Severino,&nbsp;Felipe Escudero,&nbsp;Rodrigo Demarco,&nbsp;Andrés Fuentes","doi":"10.1007/s10494-026-00740-4","DOIUrl":"10.1007/s10494-026-00740-4","url":null,"abstract":"<div>\u0000 \u0000 <p>This study investigates the effect of flow dynamics on the soot temperature and volume fraction fields in a non-premixed pulsed ethylene flame generated on a Yale burner. Soot properties were characterized through absorption/emission techniques, while Particle Image Velocimetry with zirconium dioxide tracer particles was applied to the entire flame. The resulting velocity fields were used to calculate shear strain rates in different regions of the flame. The results showed that modulation significantly affected the soot distribution, with a variation of <span>(sim)</span>12% in the soot volume fraction between consecutive phases of the cycle. During certain phases a higher injection flow rate is favored by the acoustic pulse, leading to an increased amount of fuel being burned and a higher soot formation. This behavior is related to the flow expansion in the upper regions of the flame, where high velocity zones coincide with an increment in soot temperature due to particle transport and accumulation. Also, areas exhibiting heightened strain rates are linked to elevated levels of mixing and oxidation. These regions are associated with a low soot volume fraction. This is likely due to enhanced mixing and oxidation under elevated strain rates, as suggested by previous numerical work, highlighting the suppression of soot inception and the predominance of oxidation processes during specific phases of the forcing cycle. The interactions between fluid structures and soot-rich zones were identified as a crucial aspect of overall combustion dynamics, with a direct impact on efficiency and emissions.</p>\u0000 </div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"116 3","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147606993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}