Flow, Turbulence and Combustion最新文献_第3页

Investigation of Entrainment and its Effect on Flame Stabilization in a Turbulent High Karlovitz Number Premixed Jet Flame using Direct Numerical Simulation 利用直接数值模拟研究高卡尔洛维茨数湍流预混合喷射火焰中的夹带及其对火焰稳定的影响

IF 2 3区工程技术

Flow, Turbulence and Combustion Pub Date : 2023-10-24 DOI: 10.1007/s10494-023-00500-8

Jiahao Ren, Haiou Wang, Kun Luo, Jianren Fan

{"title":"Investigation of Entrainment and its Effect on Flame Stabilization in a Turbulent High Karlovitz Number Premixed Jet Flame using Direct Numerical Simulation","authors":"Jiahao Ren, Haiou Wang, Kun Luo, Jianren Fan","doi":"10.1007/s10494-023-00500-8","DOIUrl":"10.1007/s10494-023-00500-8","url":null,"abstract":"<div><p>The stabilization of high Karlovitz number (Ka) jet flames is challenging due to the strong mean shear, and the role of entrainment on high Ka flame stabilization is not well understood. In the present work, a direct numerical simulation study of fluid entrainment and its effect on the flame stabilization in a three-dimensional turbulent high Ka premixed jet flame with a strong mean shear was carried out. The global entrainment characteristics in the turbulent jet flame was analyzed, which shows that the mass flow of the jet increases almost linearly with the streamwise distance. The turbulent/non-turbulent (T/NT) interface was investigated and the conditional statistics near the T/NT interface were analyzed. It was found that the enstrophy transport is generally balanced by the vortex stretching term and the viscous dissipation term. In the region close to the interface, the enstrophy generation from the viscous diffusion term is dominant, which has significant impact on the T/NT interface propagation. Overall, the T/NT interface propagates towards the non-turbulent region. Therefore, the species in the coflow of the non-turbulent region are entrained into the turbulent region across the T/NT interface. Various terms of species transport equations conditioned on the T/NT interface were analyzed. It was concluded that the entrainment of species such as OH plays an important role in flame stabilization in the upstream region.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"112 2","pages":"537 - 556"},"PeriodicalIF":2.0,"publicationDate":"2023-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135273906","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

Exploratory Study of the Impact of the Turbulence Model on Flame Extinction with an EDM and EDC/Finite-Rate Approach for a Line Burner Configuration 在管式燃烧器配置中采用放电加工和放电加工/定速方法探索研究湍流模型对火焰熄灭的影响

IF 2 3区工程技术

Flow, Turbulence and Combustion Pub Date : 2023-10-21 DOI: 10.1007/s10494-023-00498-z

Jeri At Thabari, Georgios Maragkos, Bart Merci

{"title":"Exploratory Study of the Impact of the Turbulence Model on Flame Extinction with an EDM and EDC/Finite-Rate Approach for a Line Burner Configuration","authors":"Jeri At Thabari, Georgios Maragkos, Bart Merci","doi":"10.1007/s10494-023-00498-z","DOIUrl":"10.1007/s10494-023-00498-z","url":null,"abstract":"<div><p>The paper presents large eddy simulations of a turbulent line burner and studies the influence of turbulence modelling, for various levels of flame extinction. The classical Smagorinsky model, as well as a static and dynamic version of a one-equation model are applied to model sub-grid scale turbulence. Within this context, two different combustion models are considered: the eddy dissipation model (EDM) with infinitely fast chemistry and the eddy dissipation concept (EDC) with simplified finite-rate chemistry. The model assessment is made through comparison to experimental data by considering both first and second order statistics. For the cases without extinction, the results indicate that the use of the dynamic one-equation turbulence model performs poorly with either of the combustion models. The analysis suggests that the dynamically determined turbulence model parameters have a significant effect in the mixing time scales and the resulting reaction rates. For the extinction cases, the use of EDC with finite-rate chemistry is able to predict fairly well the combustion efficiency in conditions far from extinction and during complete extinction. The onset to flame extinction is predicted less satisfactorily, with the discrepancies attributed to radiation modelling and the use of a simplified reaction mechanism.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"112 3","pages":"917 - 930"},"PeriodicalIF":2.0,"publicationDate":"2023-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135511585","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

Representing the Small Scales of Turbulence by Periodic Box Homogeneous Isotropic Turbulence Simulations 用周期性箱式均质各向同性湍流模拟表示湍流的小尺度

IF 2.4 3区工程技术

Flow, Turbulence and Combustion Pub Date : 2023-10-20 DOI: 10.1007/s10494-023-00497-0

Githin Tom Zachariah, Harry E. A. Van den Akker

{"title":"Representing the Small Scales of Turbulence by Periodic Box Homogeneous Isotropic Turbulence Simulations","authors":"Githin Tom Zachariah, Harry E. A. Van den Akker","doi":"10.1007/s10494-023-00497-0","DOIUrl":"10.1007/s10494-023-00497-0","url":null,"abstract":"<div><p>Large Eddy Simulations (LESs) use Sub-Grid Scale (SGS) models to account for the effects of the unresolved scales of turbulence. The complex processes that occur in the small scales make the development of SGS models challenging. This complexity is even compounded in the presence of multiphase physics due to the mutual interactions between the small-scale hydrodynamics and the dispersed phase distribution and behaviour. In this study, we propose to avoid using an SGS model and demonstrate a novel technique to use a Periodic Box (PB) Direct Numerical Simulation (DNS) solver to find and represent the local SGS turbulence for supplementing a LES. This technique involves matching the local characteristic strain rate in the LES with the large-scale characteristic strain rate in the PB DNS. For simplicity, we assume Homogeneous Isotropic Turbulence (HIT) to be a good representation of SGS turbulence. For a test case, viz. HIT, we compare the averaged turbulence spectra from the LES and the PB DNS with the exact solution from a full DNS simulation. The results show an almost seamless coupling between the large and small scales. As such, this model is more accurate than the common Smagorinsky model in describing the properties of small scales while working within the same assumptions. Further, the effective Smagorinsky constant predicted by our model and the DNS simulation agree. Finally, a two-way coupling is introduced where an effective viscosity is computed in the PB DNS and supplied back to the LES. The results show a definitive improvement in the LES while maintaining stability. The findings showcase the capability of a PB DNS to support a LES with a near-exact simulation of the SGS turbulence.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"111 4","pages":"1101 - 1126"},"PeriodicalIF":2.4,"publicationDate":"2023-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135567933","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

Energy Cascade Phenomena in Temporal Boundary Layers 时界层中的能量级联现象

IF 2 3区工程技术

Flow, Turbulence and Combustion Pub Date : 2023-10-11 DOI: 10.1007/s10494-023-00492-5

Andrea Cimarelli, Gabriele Boga, Anna Pavan, Pedro Costa, Enrico Stalio

{"title":"Energy Cascade Phenomena in Temporal Boundary Layers","authors":"Andrea Cimarelli, Gabriele Boga, Anna Pavan, Pedro Costa, Enrico Stalio","doi":"10.1007/s10494-023-00492-5","DOIUrl":"10.1007/s10494-023-00492-5","url":null,"abstract":"<div><p>The geometrically complex mechanisms of energy transfer in the compound space of scales and positions of wall turbulent flows are investigated in a temporally evolving boundary layer. The phenomena consist of spatially ascending reverse and forward cascades from the small production scales of the buffer layer to the small dissipative scales distributed among the entire boundary layer height. The observed qualitative behaviour conforms with previous results in turbulent channel flow, thus suggesting that the observed phenomenology is a robust statistical feature of wall turbulence in general. An interesting feature is the behaviour of energy transfer at the turbulent/non-turbulent interface, where forward energy cascade is found to be almost absent. In particular, the turbulent core is found to sustain a variety of large-scale wall-parallel motions at the turbulent interface through weak but persistent reverse energy cascades. This behaviour conforms with previous results in free shear flows, thus suggesting that the observed phenomenology is a robust statistical feature of turbulent shear flows featuring turbulent/non-turbulent interfaces in general.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"112 1","pages":"129 - 145"},"PeriodicalIF":2.0,"publicationDate":"2023-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136209959","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

Measurements for Characteristics of Turbulence over a Streamwise Preferential Porous Substrate 测量流向优选多孔基质上的湍流特性

IF 2 3区工程技术

Flow, Turbulence and Combustion Pub Date : 2023-10-06 DOI: 10.1007/s10494-023-00493-4

Mahiro Morimoto, Ryoma Aoki, Yusuke Kuwata, Kazuhiko Suga

{"title":"Measurements for Characteristics of Turbulence over a Streamwise Preferential Porous Substrate","authors":"Mahiro Morimoto, Ryoma Aoki, Yusuke Kuwata, Kazuhiko Suga","doi":"10.1007/s10494-023-00493-4","DOIUrl":"10.1007/s10494-023-00493-4","url":null,"abstract":"<div><p>To investigate the turbulence characteristics over a streamwise-preferential porous substrate, we design a layered porous medium that satisfies the turbulent drag-reducing conditions suggested by the direct numerical simulation (DNS) of Gómez-de Segura and García-Mayoral (J Fluid Mech 875:124–172, 2019). Planar particle image velocimetry (PIV) measurements are carried out for fully developed turbulent flows over substrates made of the layered porous medium. Two (square duct and two-dimensional channel) flow cases are considered. Streamwise-wall-normal plane measurements are performed at the bulk Reynolds numbers <span>(Re_b=)</span>5000–15000 for the square duct flows. The measurement data indicate that with the drag-reducing conditions, which are suggested by the DNS, turbulence over the porous substrate is suppressed to a similar level to that near a solid smooth wall. For further discussion, we then carry out another PIV campaign for channel flows. With streamwise-wall-normal and streamwise-spanwise plane measurements of channel flows at <span>(Re_b=)</span>3000–15000, it is observed that the turbulence level near the porous medium is more significant than that near the solid wall. To investigate why turbulence over the layered porous medium behaves unlike in the DNS, we analyse the data comparing with our previously studied porous medium turbulence. With the spanwise streak distributions and quadrant analyses, their similarity and dissimilarity of turbulence structures are discussed.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"113 1","pages":"71 - 92"},"PeriodicalIF":2.0,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135346754","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

Investigating 3-D Effects on Flashing Cryogenic Jets with Highly Resolved LES 利用高分辨率 LES 研究闪光低温喷流的三维效应

IF 2.4 3区工程技术

Flow, Turbulence and Combustion Pub Date : 2023-09-28 DOI: 10.1007/s10494-023-00485-4

Jan Wilhelm Gärtner, Andreas Kronenburg, Andreas Rees, Michael Oschwald

{"title":"Investigating 3-D Effects on Flashing Cryogenic Jets with Highly Resolved LES","authors":"Jan Wilhelm Gärtner, Andreas Kronenburg, Andreas Rees, Michael Oschwald","doi":"10.1007/s10494-023-00485-4","DOIUrl":"10.1007/s10494-023-00485-4","url":null,"abstract":"<div><p>For the development of upper stage rocket engines with laser ignition, the transition of oxidizer and fuel from the pure cryogenic liquid streams to an ignitable mixture needs to be better understood. Due to the near vacuum conditions that are present at high altitudes and in space, the injected fuel rapidly atomizes in a so-called flash boiling process. To investigate the behavior of flashing cryogenic jets under the relevant conditions, experiments of liquid nitrogen have been performed at the DLR Lampoldshausen. The experiments are accompanied by a series of computer simulations and here we use a highly resolved LES to identify 3D effects and to better interpret results from the experiments and existing 2D RANS. It is observed that the vapor generation inside the injector and the evolution of the spray in the combustion chamber differ significantly between the two simulation types due to missing 3D effects and the difference in resolution of turbulent structures. Still, the observed 3D spray dynamics suggest a suitable location for laser ignition that could be found in regions of relative low velocity and therefore expected low strain rates. Further, measured droplet velocities are compared to the velocities of notional Lagrangian particles with similar inertia as the measured droplets. Good agreement between experiments and simulations exists and strong correlation between droplet size and velocity can be demonstrated.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"111 4","pages":"1175 - 1192"},"PeriodicalIF":2.4,"publicationDate":"2023-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10494-023-00485-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135385756","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

The Influence of Boundary Conditions on Three-Dimensional Large Eddy Simulations of Calorically Perfect Gas Detonations 边界条件对热量完美气体爆破三维大涡流模拟的影响

IF 2.4 3区工程技术

Flow, Turbulence and Combustion Pub Date : 2023-09-26 DOI: 10.1007/s10494-023-00491-6

Brian Maxwell, Wei Hao Wang

{"title":"The Influence of Boundary Conditions on Three-Dimensional Large Eddy Simulations of Calorically Perfect Gas Detonations","authors":"Brian Maxwell, Wei Hao Wang","doi":"10.1007/s10494-023-00491-6","DOIUrl":"10.1007/s10494-023-00491-6","url":null,"abstract":"<div><p>In this work, we revisit the application of the compressible linear eddy model for large eddy simulation (CLEM-LES) of calorically perfect gas detonations in an attempt to clarify if the Kolmogorov number can be treated as a constant instead of a tuning parameter when no-slip boundary conditions are included in three-dimensional simulations. In its early development, the CLEM-LES with a one-step combustion chemistry model was used to simulate two-dimensional methane-oxygen detonations to gain insight on the roles and impact of turbulent mixing rates on the presence of unburned pockets of reactive gas and cellular structure. In these past simulations, special treatment of the boundary conditions was not considered, and therefore wave speeds always recovered the Chapman-Jouguet (CJ)-velocity. Moreover, tuning of the Kolmogorov number was required in order to qualitatively capture the experimentally observed flow fields. In this work we carefully perform three-dimensional simulations of detonation propagation using the CLEM-LES, and include no-slip walls as boundary conditions. Also, instead of tuning the Kolmogorov number to obtain the correct cell size, as was done in the past, we instead use a standard value of 1.5. We found that by carefully specifying the boundary conditions, and treating the Kolmogorov as a constant (thus no model calibration), both the expected propagation velocity deficit and cellular structure are recovered. Finally, upon constructing the resulting energy spectrum, we found that the kinetic energy cascade follows the well-known −5/3 power law description of incompressible turbulence in the inertial subrange, but was not symmetric nor isotropic.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"111 4","pages":"1279 - 1299"},"PeriodicalIF":2.4,"publicationDate":"2023-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134958511","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

Influence of Ridge Spacing, Ridge Width, and Reynolds Number on Secondary Currents in Turbulent Channel Flow Over Triangular Ridges 三角栅间距、栅宽和雷诺数对三角形栅上湍流通道次生流的影响

IF 2 3区工程技术

Flow, Turbulence and Combustion Pub Date : 2023-09-26 DOI: 10.1007/s10494-023-00488-1

Oleksandr Zhdanov, Thomas O. Jelly, Angela Busse

{"title":"Influence of Ridge Spacing, Ridge Width, and Reynolds Number on Secondary Currents in Turbulent Channel Flow Over Triangular Ridges","authors":"Oleksandr Zhdanov, Thomas O. Jelly, Angela Busse","doi":"10.1007/s10494-023-00488-1","DOIUrl":"10.1007/s10494-023-00488-1","url":null,"abstract":"<div><p>Most studies of secondary currents (SCs) over streamwise aligned ridges have been performed for rectangular ridge cross-sections. In this study, secondary currents above triangular ridges are systematically studied using direct numerical simulations of turbulent channel flow. The influence of ridge spacing on flow topology, mean flow, and turbulence statistics is investigated at two friction Reynolds numbers, 550 and 1000. In addition, the effects of ridge width on SCs, which have not previously been considered for this ridge shape, are explored. The influence of SCs on shear stress statistics increases with increased ridge spacing until SCs fill the entire channel. One of the primary findings is that, for ridge configurations with pronounced secondary currents, shear stress statistics exhibit clear Reynolds number sensitivity with a significant growth of dispersive shear stress levels with Reynolds number. In contrast to rectangular ridges, no above-ridge tertiary flows are observed for the tested range of ridge widths. Flow visualisations of SCs reveal the existence of corner vortices that form at the intersection of the lateral ridge sides and the smooth-wall sections. These are found to gradually disappear as ridges increase in width. Premultiplied spectra of streamwise velocity fluctuations show strong dependency on the spanwise sampling location. Whereas spanwise averaged spectra show no strong modifications by SCs, a significant increase of energy levels emerges at higher wavelengths for spectra sampled at the spanwise locations that correspond to the centres of the secondary currents.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"112 1","pages":"105 - 128"},"PeriodicalIF":2.0,"publicationDate":"2023-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10494-023-00488-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134958378","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

Numerical Investigation on the Head-on Quenching (HoQ) of Laminar Premixed Lean to Stoichiometric Ammonia–Hydrogen-Air Flames 关于层流预混合稀薄至稳定氨氢空气火焰迎面淬火 (HoQ) 的数值研究

IF 2.4 3区工程技术

Flow, Turbulence and Combustion Pub Date : 2023-09-20 DOI: 10.1007/s10494-023-00489-0

Chunkan Yu, Liming Cai, Cheng Chi, Syed Mashruk, Agustin Valera-Medina, Ulrich Maas

{"title":"Numerical Investigation on the Head-on Quenching (HoQ) of Laminar Premixed Lean to Stoichiometric Ammonia–Hydrogen-Air Flames","authors":"Chunkan Yu, Liming Cai, Cheng Chi, Syed Mashruk, Agustin Valera-Medina, Ulrich Maas","doi":"10.1007/s10494-023-00489-0","DOIUrl":"10.1007/s10494-023-00489-0","url":null,"abstract":"<div><p>The Head-on Quenching (HoQ) of laminar premixed ammonia–hydrogen-air flames under lean to stoichiometric condition is numerical investigated. Detailed chemistry including 34 reactive species and detailed multi-component transport model including thermal diffusion (Soret effect) are applied. The quenching distance is considered as a representative quantity for the HoQ process, and the influence of different system parameters on it has been investigated. These parameters involve fuel/air equivalence ratios, hydrogen content in gas mixture and pressure. It was found that an increase of quenching distance can be caused by a lower hydrogen addition and a leaner mixture condition. Furthermore, it was found that, regardless of the gas mixture, the quenching distance decreases monotonically with increasing pressure, obeying a power function with the exponent <span>(-)</span> 0.7. Moreover, numerical results show a relation between the quenching Peclet number and the dimensionless wall heat flux normalized by the flame power. Additionally, sensitivities of quenching distances with respect to the transport model, considering the heat loss in the wall and the chemical kinetics are studied.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"111 4","pages":"1301 - 1322"},"PeriodicalIF":2.4,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10494-023-00489-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136309590","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

Effects of Synthetic Jets on Swirl Inflow in a Variable-Geometry Twin Air-Intake 合成射流对可变几何双进气口漩涡气流的影响

IF 2.4 3区工程技术

Flow, Turbulence and Combustion Pub Date : 2023-09-20 DOI: 10.1007/s10494-023-00481-8

Krishna Kumar Rajnath Yadav, Akshoy Ranjan Paul, Anuj Jain, Firoz Alam

{"title":"Effects of Synthetic Jets on Swirl Inflow in a Variable-Geometry Twin Air-Intake","authors":"Krishna Kumar Rajnath Yadav, Akshoy Ranjan Paul, Anuj Jain, Firoz Alam","doi":"10.1007/s10494-023-00481-8","DOIUrl":"10.1007/s10494-023-00481-8","url":null,"abstract":"<div><p>Air intakes are an integral part of contemporary passenger and military aircraft engines. Their impact on aerodynamic performance across the entire flight envelope is critical to aircraft flight safety, efficiency, and manoeuvrability, especially at high Mach numbers due to shock waves. The high demand for reductions in aircraft weight and size and enhancements in durability, comfort, and thermal and radar signatures compel researchers and engineers to explore new designs and develop efficient air intakes for high-performance aircraft engines. Although a number of studies on air intake have been conducted and reported in the open literature, there is little information available in the public domain on bifurcated twin air intakes using synthetic jet. As a result, the primary goal of this research is to use computational fluid dynamics modelling to investigate the effects of synthetic jets on swirl inflow variable geometry twin air intake aerodynamic performance over a range of Reynolds numbers. Some important parameters (distortion coefficient, non-uniformity index, swirl coefficient, and static and total pressure coefficients) were investigated. Both static and total pressure recovery have been increased at all swirl numbers. A significant decrease in distortion coefficient and swirl coefficient has also been achieved, reaching a 53% reduction in the distortion coefficient and a 62% reduction in the swirl coefficient. The reduction in the non-uniformity index is achieved by 62% for the controlled flow case. The findings show that synthetic jets are effective in controlling the flow separation in the twin air intakes and enhancing aerodynamic performance.</p></div>","PeriodicalId":559,"journal":{"name":"Flow, Turbulence and Combustion","volume":"111 4","pages":"1193 - 1225"},"PeriodicalIF":2.4,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10494-023-00481-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136309883","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