Flow, Turbulence and Combustion最新文献

Large Eddy Simulation of the Piston Boundary Layer Evolution During the Compression Stroke in a Motored Internal Combustion Engine 内燃机压缩行程中活塞边界层演化的大涡模拟

IF 2 3区工程技术

Flow, Turbulence and Combustion Pub Date : 2025-04-14 DOI: 10.1007/s10494-025-00649-4

Andrea Pati, Max Hasenzahl, Suad Jakirlic, Christian Hasse

{"title":"Large Eddy Simulation of the Piston Boundary Layer Evolution During the Compression Stroke in a Motored Internal Combustion Engine","authors":"Andrea Pati, Max Hasenzahl, Suad Jakirlic, Christian Hasse","doi":"10.1007/s10494-025-00649-4","DOIUrl":"10.1007/s10494-025-00649-4","url":null,"abstract":"<div><p>This work examines the momentum boundary layer evolution on the piston top of the Darmstadt optically accessible Internal Combustion Engine (ICE). For this purpose, a 3D-CFD wall-resolved Large Eddy Simulation (LES) under motored conditions was deployed. The piston wall is resolved down to 25 <span>(upmu)</span>m, corresponding to <span>({y^ + } < 1)</span>. For statistical purposes and to compare with experimental data, 33 consecutive engine cycles are simulated. A large-scale tumble motion characterizes the flow field. This flow impinges on the piston on the exhaust side, it moves along the flat piston wall and detaches on the intake side. The near-wall velocities of the simulations align well with the experiment. Analysis revealed regions of Favorable Pressure Gradient (FPG) on the exhaust side and Adverse Pressure Gradient (APG) on the intake side, separated by a sharp pressure inversion zone. The near-wall flow accelerates and then decelerates until detachment. Analysis of the non-dimensional <span>({u^ + } - {y^ + })</span> profiles reveals the absence of a logarithmic region in the boundary layer. This scaling procedure is sensitive to thermo-physical properties like density and viscosity that vary across the boundary layer, which complicates comparisons with canonical studies. The shape factor of the boundary layer suggests a fully turbulent state despite the low momentum thickness-based Reynolds number. The boundary layer height increases from the exhaust towards the intake side, especially in the presence of strong pressure gradients. Pressure gradients acting perpendicular to the boundary layer are observed. The comparison of ensemble-averaged and single-cycle instantaneous data shows high levels of cyclic fluctuations.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"114 4","pages":"1269 - 1295"},"PeriodicalIF":2.0,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10494-025-00649-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143856647","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}

引用次数: 0

PIV Measurements and Validation of RANS Solutions for Plane Turbulent Impinging Co-Flowing and Angled Jets at Moderate Reynolds Numbers 中等雷诺数下平面湍流撞击共流和角度射流的PIV测量和RANS解的验证

IF 2 3区工程技术

Flow, Turbulence and Combustion Pub Date : 2025-04-14 DOI: 10.1007/s10494-025-00650-x

Claudio Alanis Ruiz, Twan van Hooff, Bert Blocken, GertJan van Heijst

{"title":"PIV Measurements and Validation of RANS Solutions for Plane Turbulent Impinging Co-Flowing and Angled Jets at Moderate Reynolds Numbers","authors":"Claudio Alanis Ruiz, Twan van Hooff, Bert Blocken, GertJan van Heijst","doi":"10.1007/s10494-025-00650-x","DOIUrl":"10.1007/s10494-025-00650-x","url":null,"abstract":"<div><p>Turbulent impinging jet (TIJ) flows are a canonical type of flow that is present in nature and in a wide range of industrial applications, making their study indispensable. Among them, multiple co-flowing and angled jets offer possibilities for various practical applications. However, fundamental information on these particular jet configurations is scarce, and there is also a lack of data for validating numerical simulations of these jet flows. Therefore, this paper presents an experimental analysis of isothermal plane turbulent impinging co-flowing and angled jets at moderate Reynolds numbers (<i>Re</i><sub><i>jet</i></sub> ≈ 8,700 and 10,000) and height-to-width ratio (<i>γ</i> = 40.5) utilizing 2D particle image velocimetry (PIV). It also validates the results of several RANS turbulence models that are commonly used for simulating single straight TIJs: standard <i>k-ε</i> (SKE) model, realizable <i>k-ε</i> model (RKE), renormalization group (RNG) <i>k-ε</i> model, baseline (BSL) <i>k-ω</i> model, shear-stress transport (SST) <i>k-ω</i> model, and a Reynolds-stress model (RSM). The analysis and validation focus on detailed velocity measurements while also providing insights into turbulence parameters. Results reveal strong similarities between the two analyzed TIJs and single straight TIJs at the developed free-jet (or combined jet region for the co-flowing jets configuration) and impingement regions. The validation study demonstrates that relatively inexpensive RANS simulations in combination with typical <i>k-ε</i> turbulence models are capable of resolving the mean velocity field of the two investigated TIJ configurations with good accuracy, which is especially the case for the RNG <i>k-ε</i> turbulence model that yields a very good match with the PIV data throughout.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"114 4","pages":"1113 - 1147"},"PeriodicalIF":2.0,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10494-025-00650-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143856646","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}

引用次数: 0

Large Eddy Simulations of a Turbulent Premixed Swirling Flame with Finite-Rate Chemistry and Flame-Wrinkling Turbulent Combustion Models 用有限速率化学和火焰起皱湍流燃烧模型模拟湍流预混旋转火焰的大涡

IF 2 3区工程技术

Flow, Turbulence and Combustion Pub Date : 2025-04-09 DOI: 10.1007/s10494-025-00652-9

Alessandro Ercole, Daniel Lörstad, Christer Fureby

{"title":"Large Eddy Simulations of a Turbulent Premixed Swirling Flame with Finite-Rate Chemistry and Flame-Wrinkling Turbulent Combustion Models","authors":"Alessandro Ercole, Daniel Lörstad, Christer Fureby","doi":"10.1007/s10494-025-00652-9","DOIUrl":"10.1007/s10494-025-00652-9","url":null,"abstract":"<div><p>Lean, premixed, swirl-stabilized flames are widely used in modern Dry Low Emissions gas turbine combustors; however, the turbulent combustion process under those conditions is known to be extremely sensitive and prone to instabilities. Numerical simulations can be a valuable tool in predicting the effects of alternative fuels; however, the sensitivity of the results to different models ought to be outlined. In this work, we present the results of Large Eddy Simulations performed on the CECOST burner with both Finite Rate Chemistry and Flamelet Progress Variable combustion models, non-adiabatic boundary conditions, and radiation modeling. The results highlight a surprising sensitivity of the simulation results in terms of mean fields, flame macrostructure, and flame dynamics. We discuss the model effects on the coupling mechanisms between turbulence and combustion, e.g., thermal expansion, and we conclude that, in particularly sensitive cases, they are capable of locally altering the flowfield to the extent it influences key flow structures on which flame stabilization relies. Additionally, the interaction between the smallest resolved scales of turbulence and the flame front is also affected, resulting in distinct flame dynamics.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"114 4","pages":"1377 - 1404"},"PeriodicalIF":2.0,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10494-025-00652-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143856419","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}

引用次数: 0

LES Modeling of the DLR Generic Single-Cup Spray Combustor: Comparison of Exploratory Category C Jet Fuels DLR通用单杯喷雾燃烧器的LES建模：探索性C类喷气燃料的比较

IF 2 3区工程技术

Flow, Turbulence and Combustion Pub Date : 2025-04-03 DOI: 10.1007/s10494-025-00653-8

Arvid Åkerblom, Christer Fureby

{"title":"LES Modeling of the DLR Generic Single-Cup Spray Combustor: Comparison of Exploratory Category C Jet Fuels","authors":"Arvid Åkerblom, Christer Fureby","doi":"10.1007/s10494-025-00653-8","DOIUrl":"10.1007/s10494-025-00653-8","url":null,"abstract":"<div><p>The combustion of conventional Jet A, alongside two alternative jet fuels, C1 and C5, is simulated with Large Eddy Simulations (LES) in a generic single-cup spray combustor during idle and cruise conditions. The spray is modeled using Lagrangian particle tracking and the combustion chemistry of each fuel is modeled by skeletal reaction mechanisms. The volatility and atomizability of each fuel directly affect the spray penetration depth, with Jet A having the longest spray and C5 the shortest. All fuels have qualitatively similar flames at idle conditions, but the Jet A flame is relatively lifted at cruise conditions. C1 and C5 have similar flames despite different spray lengths, likely due to the rapid breakup of C1. The fuels produce different emission profiles, which is connected to their respective H/C ratios, equivalence ratios, and aromatics contents. NO<sub>x</sub> emissions are particularly affected by the mixture fraction in the flame, resulting in high NO<sub>x</sub> emissions for the compact C1 and C5 flames. Thermoacoustic oscillations are observed in all simulations but are strongest for C1 and C5, which we hypothesize is a result of their high volatility.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"114 4","pages":"1315 - 1339"},"PeriodicalIF":2.0,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10494-025-00653-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143856416","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}

引用次数: 0

High Gas Void Fraction Two-Phase Flow Measurement Based on One-Dimensional Acoustic Wave in Pipeline 基于一维声波的管道高含气率两相流测量

IF 2 3区工程技术

Flow, Turbulence and Combustion Pub Date : 2025-04-02 DOI: 10.1007/s10494-025-00646-7

Rui Pei, Danping Jia, Lianggui Wang, Zhensheng Zang, Bo Liu, Yong Sun

{"title":"High Gas Void Fraction Two-Phase Flow Measurement Based on One-Dimensional Acoustic Wave in Pipeline","authors":"Rui Pei, Danping Jia, Lianggui Wang, Zhensheng Zang, Bo Liu, Yong Sun","doi":"10.1007/s10494-025-00646-7","DOIUrl":"10.1007/s10494-025-00646-7","url":null,"abstract":"<div><p>Parameter measurement of gas–liquid two-phase flow with a high gas void fraction has received great attention in the research field of multiphase flow. As a flowmeter on the sonar principle, the line array-mounted piezoelectric sensors can be applied for gas void fraction measurement of gas–liquid two-phase flow. Firstly, the formula for calculating the density and sound velocity of the medium is analyzed, including: the gas equation of air, the AGA8 and AGA10 standards of natural gas, and the IAPWS-IF97 model of water, combined with the Wood formula and the one-dimensional acoustic attenuation formula of the pipeline, it is deduced that in the gas void fraction > 50% high zone where the gas well is located, the mixed sound velocity increases with the increase of the gas void fraction, showing a monotony increasing correspondence. Secondly, the MVDR beamforming algorithm is applied to solve the “acoustic ridge” in the <span>(k - omega)</span> domain based on the one-dimensional acoustic model of the pipeline to realize the mixed sound velocity measurement of two-phase flow. Finally, the air and water standard device was used to replicate on-site gas well high gas void fraction experiments. The relative error was 2.62% and repeatability was 1.50% for vertically mounted large array spacing. The accuracy meets the requirements for gas well measurements, verifying the feasibility of using the acoustic method to measure gas void fraction. Therefore, it is of great engineering guiding significance to realize the measurement of gas void fraction in the on-site gas well.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"114 4","pages":"1201 - 1232"},"PeriodicalIF":2.0,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143856445","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}

引用次数: 0

Experimental and Numerical Investigation of Scale Effects on the Flow Over a Sedan Vehicle 轿车流动尺度效应的实验与数值研究

IF 2 3区工程技术

Flow, Turbulence and Combustion Pub Date : 2025-04-01 DOI: 10.1007/s10494-025-00651-w

Guilherme Espíndola da Silva, Rafael Rezende Dias, Odenir de Almeida, Anderson Ramos Proença

{"title":"Experimental and Numerical Investigation of Scale Effects on the Flow Over a Sedan Vehicle","authors":"Guilherme Espíndola da Silva, Rafael Rezende Dias, Odenir de Almeida, Anderson Ramos Proença","doi":"10.1007/s10494-025-00651-w","DOIUrl":"10.1007/s10494-025-00651-w","url":null,"abstract":"<div><p>Experiments and numerical modeling on vehicle aerodynamics were conducted in a Reynolds (Re) number one order of magnitude lower than that of typical full-scale application. Drag coefficient, velocity profile measurements and flow visualization were the focus with the proposition of comparing scale effects of a 1:10 sedan passenger vehicle model with numerical data from full-scale (1:1) based on the Reynolds Averaged Navier–Stokes (RANS) approach. After the validation of the numerical approach at 1:10 scale, additional investigation of sharp and rounded fillets presented on the car’s geometry showed to be relevant to the calculation of the separating shear layers and drag prediction, although the general wake structures are qualitatively similar. Effects of the reduced scale are translated to low Reynolds number where viscous effects starts to play a role. Detailed flow features such as recirculating regions and reversing flow acts on the model’s surface while the near wake velocity field is well captured and evaluated both experimentally and numerically. The results permitted to characterize flow details based on Re number flow, to show the effects of sharp corners on the model and to scrutinize the influence of scale effects on vehicle’s aerodynamics.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"114 4","pages":"1149 - 1177"},"PeriodicalIF":2.0,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143856371","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}

引用次数: 0

Evolution of a Jet-in-Coflow 同向气流喷射的演变

IF 2 3区工程技术

Flow, Turbulence and Combustion Pub Date : 2025-03-11 DOI: 10.1007/s10494-025-00648-5

Rishikesh Sampat, Ferry Schrijer, Gangoli Rao Arvind

{"title":"Evolution of a Jet-in-Coflow","authors":"Rishikesh Sampat, Ferry Schrijer, Gangoli Rao Arvind","doi":"10.1007/s10494-025-00648-5","DOIUrl":"10.1007/s10494-025-00648-5","url":null,"abstract":"<div><p>The jet-in-coflow is a two-stream configuration having engineering applications in combustors and gas turbine engine exhausts. In practical systems, the coflow generates a boundary layer of the outer wall of the jet pipe and may also have a certain level of turbulence. In the current work, the evolution of this flow configuration is studied using an air-air turbulent jet in a low turbulence coflow (turbulence intensity < 6%), and the 2D velocity field is measured by planar particle image velocimetry. Cases of varying coflow ratio (ratio of coflow velocity to jet velocity) of 0 (turbulent free jet), 0.09, 0.15, and 0.33 are generated by keeping a constant velocity jet (Re = 14000) and varying the coflow velocity. The trends of jet centerline properties such as velocity decay, jet spread, and jet momentum of jet-in-coflow cases, scaled to represent an equivalent free jet, show deviations from that of the turbulent free jet. The radial profile of mean velocity shows a region of velocity deficit, compared to a turbulent free jet, on the coflow side in the jet-in-coflow cases. In contrast, the turbulence intensity and Reynolds shear stress profiles show an enhanced peak near the interface for the jet-in-coflow cases. Further, conditional statistics were extracted by detecting the interface between the jet and the surroundings, wherein the same trends are observed. The low turbulence levels of the coflow have little effect on the jet/coflow interface, as seen by the conditional enstrophy diffusion and tortuosity compared to a turbulent free jet. The differences at the jet/coflow interface of a jet-in-coflow with respect to a turbulent free jet are attributed to the boundary layer initially developed by the turbulent coflow over the pipe generating the jet, and these are seen throughout the near-to-intermediate field (0<span>(le)</span>x/D<span>(le)</span>40).</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"114 4","pages":"1087 - 1111"},"PeriodicalIF":2.0,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10494-025-00648-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143856600","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}

引用次数: 0

Advances in Turbulence, Heat and Mass Transfer 湍流、传热和传质的进展

IF 2 3区工程技术

Flow, Turbulence and Combustion Pub Date : 2025-03-05 DOI: 10.1007/s10494-025-00644-9

Kemal Hanjalić, Domenico Borello, Kazuhiko Suga, Paolo Venturini

引用次数: 0

Flow Separation Control of a Vertical Stabiliser Using a Rudder-Mounted Slat 采用舵板的垂直稳定器流动分离控制

IF 2 3区工程技术

Flow, Turbulence and Combustion Pub Date : 2025-02-24 DOI: 10.1007/s10494-025-00640-z

Mahmud Jamil Muhammad, Yaxing Wang, Xuerui Mao, Kwing-So Choi

引用次数: 0

Numerical Simulation of the Agglomeration Behaviour of Spheroidal Particle Pairs in Chaotic Flows 混沌流动中球形粒子对团聚行为的数值模拟

IF 2 3区工程技术

Flow, Turbulence and Combustion Pub Date : 2025-02-24 DOI: 10.1007/s10494-025-00635-w

Jacob P. Anderson, Lee F. Mortimer, Timothy N. Hunter, Jeffrey Peakall, Michael Fairweather

{"title":"Numerical Simulation of the Agglomeration Behaviour of Spheroidal Particle Pairs in Chaotic Flows","authors":"Jacob P. Anderson, Lee F. Mortimer, Timothy N. Hunter, Jeffrey Peakall, Michael Fairweather","doi":"10.1007/s10494-025-00635-w","DOIUrl":"10.1007/s10494-025-00635-w","url":null,"abstract":"<div><p>Interactions between attractive spheroidal particles are studied in boxes of chaotic flow under the action of a homogeneous and isotropic forcing technique. The fully resolved fluid field and structure-resolved particle–fluid coupling regime are obtained through direct numerical simulation and an immersed boundary method. Agglomeration outcomes are accommodated through attractive van der Waals forces, suitably adapted to consider the orientational dependencies associated with the non-spherical shape. Binary particle interactions are first studied in quiescent conditions, as well as in a periodic box of chaotic fluid flow. The latter is forced using a stochastic method, where the magnitude of the velocity fluctuations and Taylor–Reynolds number are chosen based on those typically seen in nuclear waste processing scenarios. Differences in particle interaction behaviours are presented for the cases of disks and needles, with the role of orientation and kinetic energy in determining interaction outcomes analysed and contrasted with spheres. Results indicate that needles have the highest agglomeration propensity in the chaotic fluid, followed by spheres, and then disks. Lastly, the inclusion of attractive orientationally-dependent interaction forces promotes alignment between the symmetry axes of spheroidal particle pairs, whilst the increased action of the fluid was also seen to promote alignment between the interacting particles when compared to the quiescent case.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"114 Heat and Mass Transfer","pages":"941 - 965"},"PeriodicalIF":2.0,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10494-025-00635-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143612301","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}

引用次数: 0