Journal of Fluids and Structures最新文献

Effect of incidence angle on the wake of a wall mounted slotted cylinder in an open channel flow

IF 3.4 2区工程技术

Journal of Fluids and Structures Pub Date : 2025-04-26 DOI: 10.1016/j.jfluidstructs.2025.104325

John A. Boamah , A.-M. Shinneeb , R. Balachandar

{"title":"Effect of incidence angle on the wake of a wall mounted slotted cylinder in an open channel flow","authors":"John A. Boamah , A.-M. Shinneeb , R. Balachandar","doi":"10.1016/j.jfluidstructs.2025.104325","DOIUrl":"10.1016/j.jfluidstructs.2025.104325","url":null,"abstract":"<div><div>This experimental study investigates the wake flow generated by a vertically, wall-mounted slotted-cylinder in shallow channel flow. The slot, uniformly cut along the central plane of the cylinder, has a thickness equal to 0.1 times the cylinder diameter. The primary parameter examined is the incidence angle <em>θ</em> between the slot axis and the main flow direction, selected by rotating the slotted-cylinder clockwise to four different positions. The study aims to understand the impact of <em>θ</em> on the wake flow characteristics by investigating both the instantaneous and mean velocity fields, as well as the coherent structures. The Reynolds number, based on the water depth, is approximately 25,000. Particle image velocimetry (PIV) measurements were conducted along the vertical mid-plane and on three horizontal planes.</div><div>The results revealed the formation of three-dimensional (3D) mean recirculation zones in the wake of the cylinder without a slot, resembling a counter-rotating U-shaped vortical structure. For θ ≥ 60°, this 3D shape persists, while for θ < 60°, it varies by the angle. The jet emanating from the slot suppresses velocity fluctuations when injected into the wake region at incidence angles θ < 60° In contrast, at θ ≥ 60°, there is a transition to a stimulating effect that enhances turbulent kinetic energy (TKE) production. Proper orthogonal decomposition (POD) results highlight differences in kinetic energy transfer to the turbulent flow across various cases of the slotted-cylinder. Moreover, the slot flow exhibits both blowing and suction effects, with varying intensity and dominance throughout the shallow water layer.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"136 ","pages":"Article 104325"},"PeriodicalIF":3.4,"publicationDate":"2025-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143874783","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Synthesis and characterisation of turbulent flows to predict fatigue loading of tidal turbines in arrays

IF 3.4 2区工程技术

Journal of Fluids and Structures Pub Date : 2025-04-24 DOI: 10.1016/j.jfluidstructs.2025.104321

Hannah Mullings, Pablo Ouro, Tim Stallard

{"title":"Synthesis and characterisation of turbulent flows to predict fatigue loading of tidal turbines in arrays","authors":"Hannah Mullings, Pablo Ouro, Tim Stallard","doi":"10.1016/j.jfluidstructs.2025.104321","DOIUrl":"10.1016/j.jfluidstructs.2025.104321","url":null,"abstract":"<div><div>The onset flows used for tidal turbine design are, at present, based on simplifications of the naturally occurring tidal flow, and design standards consider in-wake loading based on an effective turbulence parameter. This work uses a quasi-steady blade element momentum model to assess alternative unsteady onset flow characterisation methods for prediction of the fatigue loading of turbines, when operating in the complex onset flows that occur in an array. Fatigue loads are evaluated for each turbine within a two-row array using onset turbulent flow from both a large eddy simulation and synthesised by superposition of shear, an empirical wake model and a spectral turbulence model. This is shown to provide blade damage equivalent loads within 1% for a turbine operating in the highest transverse shear region when compared to the direct use of the Large Eddy Simulation (LES) flow fields. Fatigue loads vary with turbulence and onset shear. Approaches for characterising such flows and resultant loads are evaluated including based on effective turbulence and on the signal to noise ratio (SNR) of the relative velocity to the blade at a radial position close to the centroid of the load. In isolation each approach provides loading to within 20% of the predicted trend for only up to 50% of cases. However, a combined approach considering the SNR when greater than 0.2 enables the SNR method to calculate to within 20% of the predicted trend for 97% of cases. For the cases where the SNR value is less than 0.2, the predicted trend from the relationship between effective turbulence and normalised damage equivalent load, can predict the loads to within 20% for 88% of the cases.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"136 ","pages":"Article 104321"},"PeriodicalIF":3.4,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143869787","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Modelling vegetation as complex structures in fluid–filament interaction using the elastically-articulated body method

IF 3.4 2区工程技术

Journal of Fluids and Structures Pub Date : 2025-04-23 DOI: 10.1016/j.jfluidstructs.2025.104323

Rufus E. Dickinson , Timothy I. Marjoribanks , Christopher J. Keylock , Alessandro Palmeri

{"title":"Modelling vegetation as complex structures in fluid–filament interaction using the elastically-articulated body method","authors":"Rufus E. Dickinson , Timothy I. Marjoribanks , Christopher J. Keylock , Alessandro Palmeri","doi":"10.1016/j.jfluidstructs.2025.104323","DOIUrl":"10.1016/j.jfluidstructs.2025.104323","url":null,"abstract":"<div><div>Fluid–structure interactions in the built and natural environment commonly involve complex, heterogeneous structures. For example, terrestrial and aquatic vegetation species are morphologically complex, which is a factor not fully captured in many models used to understand important aspects of flow-vegetation dynamics. In this study, we develop and validate a multi-body method for modelling fluid interaction with slender structures (‘filaments’) in complex assemblies. This work uses Featherstone’s Articulated Body Algorithm to permit 3D simulation of connected assemblies of filaments. It includes development of an elasticity model for filament bending at large angles and a novel multi-body method for simulating the added mass effect. The model’s capabilities are validated through comparison with linear beam dynamics and three experimental studies of fluid–filament interaction from the literature. These are (1) flow-induced reconfiguration of heterogeneous and curved filaments, (2) resonance and flow-induced reconfiguration of filament assemblies and (3), wave-induced dynamics of a filament with added mass. The model is shown to be competitively accurate with existing filament dynamics models while extending modelling capability to multi-stem assemblages. Results from the model application demonstrate the importance of representing complex morphologies for accurately predicting flow-vegetation interactions.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"136 ","pages":"Article 104323"},"PeriodicalIF":3.4,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143864088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Large eddy simulation of tip and Karman vortices around a square prism: dynamic characteristics and their impact on lift force

IF 3.4 2区工程技术

Journal of Fluids and Structures Pub Date : 2025-04-23 DOI: 10.1016/j.jfluidstructs.2025.104326

Qingshan Yang , Ling Zhao , Wenshan Shan , Kunpeng Guo , Francesca Lupi , Tong Zhou , Xinyi Yue

{"title":"Large eddy simulation of tip and Karman vortices around a square prism: dynamic characteristics and their impact on lift force","authors":"Qingshan Yang , Ling Zhao , Wenshan Shan , Kunpeng Guo , Francesca Lupi , Tong Zhou , Xinyi Yue","doi":"10.1016/j.jfluidstructs.2025.104326","DOIUrl":"10.1016/j.jfluidstructs.2025.104326","url":null,"abstract":"<div><div>As a crucial component in the wind resistance design framework, flow-around analysis plays an essential role in assessing wind effects on structures. In this study, the dynamic behavior of tip- and Karman vortex around a ground-mounted finite length square prism (with an aspect ratio <em>H</em>/<em>B</em> = 9) subjected to atmospheric boundary layer flow representative of suburban terrain, and their relationship to lift force are investigated using large eddy simulation (LES). The Reynolds number based on the square prism width and incoming velocity is <span><math><mrow><mtext>Re</mtext><mo>=</mo><mn>3.0</mn><mo>×</mo><msup><mrow><mn>10</mn></mrow><mn>4</mn></msup></mrow></math></span>. By combining with multiple-point synchronous pressure measurements and particle image velocimetry (PIV) wind tunnel tests, as well as other existing research, the wind loads characteristics are thoroughly examined from the perspective of mean and fluctuating wind pressure distribution on the model surface, local aerodynamic force distribution and overturning moments. Through time- and frequency domain analysis, two distinct lift fluctuation patterns are identified. The three-dimensional vortex structure analysis reveals that the Low-Amplitude Fluctuation (LAF) and High-Amplitude Fluctuation (HAF) of the lift force correspond to symmetrical and alternating vortex-shedding patterns, respectively. Symmetrical vortex shedding is primarily influenced by the downwash of tip vortex, while alternating vortex shedding pattern is driven by the Karman vortex. The notable differences in lift force fluctuation characteristics at various spanwise positions are associated with the range of influence exerted by the tip vortex downwash near the top of the square prism. The identification of the two lift force fluctuation patterns has practical implications for wind load assessment and structural design.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"136 ","pages":"Article 104326"},"PeriodicalIF":3.4,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143864089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Wind turbulence around a bridge deck in full scale

IF 3.4 2区工程技术

Journal of Fluids and Structures Pub Date : 2025-04-21 DOI: 10.1016/j.jfluidstructs.2025.104313

Nicolò Daniotti , Jasna B. Jakobsen , Jonas T. Snæbjörnsson , Etienne Cheynet

{"title":"Wind turbulence around a bridge deck in full scale","authors":"Nicolò Daniotti , Jasna B. Jakobsen , Jonas T. Snæbjörnsson , Etienne Cheynet","doi":"10.1016/j.jfluidstructs.2025.104313","DOIUrl":"10.1016/j.jfluidstructs.2025.104313","url":null,"abstract":"<div><div>This paper studies the interaction between atmospheric turbulence and a closed-box bridge girder using new data acquired on the Lysefjord Bridge in Norway. Two sonic anemometers installed near the deck edges provided wind turbulence data, which were compared to observations of the incoming flow. The investigation provides insights into the distortion of natural wind both upstream and downstream of the deck, and the vortex-shedding process past the deck’s leeward side. In the near-wake region, the pronounced three-dimensionality of the flow was identified and its correlation with the yaw angle of the incident flow was established. Vertical velocity fluctuations served as an indicator of the vortex shedding process, and Strouhal number estimates were found to exhibit a certain sensitivity to the turbulence intensity in the approaching flow. The results discussed contribute to advancing the understanding of full-scale bridge aerodynamics and provide valuable data for validating and improving wind load models. The findings have implications for the design and safety of long-span bridges exposed to atmospheric turbulence.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"135 ","pages":"Article 104313"},"PeriodicalIF":3.4,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143851672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Motion of a barge beside a fixed box: Improved relative velocity roll damping estimates, and experiments

IF 3.4 2区工程技术

Journal of Fluids and Structures Pub Date : 2025-04-20 DOI: 10.1016/j.jfluidstructs.2025.104319

Yutao Wang , Hugh Wolgamot , Wenhua Zhao

{"title":"Motion of a barge beside a fixed box: Improved relative velocity roll damping estimates, and experiments","authors":"Yutao Wang , Hugh Wolgamot , Wenhua Zhao","doi":"10.1016/j.jfluidstructs.2025.104319","DOIUrl":"10.1016/j.jfluidstructs.2025.104319","url":null,"abstract":"<div><div>Side-by-side offloading is currently the most common operation by which a Floating LNG (FLNG) facility transfers liquified cargo onto a carrier. Operability is limited by a range of criteria, of which the relative motion between the two vessels is one of the most critical. As the FLNG is relatively larger and does not move as much in response to waves, the prediction of carrier motion is thus of great importance in operability prediction. Roll motion is strongly influenced by viscous damping and is therefore typically difficult to predict within a potential flow framework. This study presents a comparison of a numerical model of vessel motions, based on linear potential flow theory, and experiments conducted in a deep water wave basin, where both vessels are simplified rectangular boxes. The roll damping formulation used to add viscous damping in the time domain is a particular focus of the numerical modelling. It is observed that using roll methods developed for isolated vessels may under-estimate roll damping for the scenario where two vessels are closely positioned, as the second hull in proximity significantly alters the surrounding flow field. This paper therefore proposes a modification to a conventional roll damping method, known as the Ikeda method, by introducing a relative velocity formulation that takes into account the flow field around the hull, which includes any possible effects from gap resonance. This modified method is shown to generate improved roll damping predictions compared to standard practice. Overall, the proposed method remains within the linear potential flow framework using standard coefficients, meaning that it can be readily integrated into engineering practice.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"135 ","pages":"Article 104319"},"PeriodicalIF":3.4,"publicationDate":"2025-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143850530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical simulation of the oblique water impact of double curvature bodies involving suction and cavitation phenomena

IF 3.4 2区工程技术

Journal of Fluids and Structures Pub Date : 2025-04-18 DOI: 10.1016/j.jfluidstructs.2025.104322

M. Goron , A. Tassin , B. Langrand , E. Spinosa , A. Del Buono , N. Jacques , T. Fourest , A. Iafrati

{"title":"Numerical simulation of the oblique water impact of double curvature bodies involving suction and cavitation phenomena","authors":"M. Goron , A. Tassin , B. Langrand , E. Spinosa , A. Del Buono , N. Jacques , T. Fourest , A. Iafrati","doi":"10.1016/j.jfluidstructs.2025.104322","DOIUrl":"10.1016/j.jfluidstructs.2025.104322","url":null,"abstract":"<div><div>The present study aims to assess the capability of a numerical method to model hydrodynamic impacts representative of an aircraft ditching. The considered numerical method is based on the Finite Element explicit solver <em>Radioss</em> and a Coupled Eulerian–Lagrangian approach. The fluid–structure interaction is dealt with using an immersed contact interface and a penalty coupling method. The oblique water impacts of three different fuselage sections have been studied based on the experimental campaigns carried out during the European project SARAH at the High-Speed Ditching Facility of CNR-INM in Rome, Italy. The results are presented in terms of force coefficient, local relative pressure, and free surface elevation. The effect of the coupling stiffness and size of the fluid elements on the numerical results is analysed to assess the robustness of the numerical method. The numerical method shows a satisfying capability to reproduce most of the experimental results. Particular attention is given to the capability of the numerical method to describe the suction and cavitation phenomena. The effect of the specimens’ transversal cross-section, the specimens’ longitudinal curvature and the development of cavitation phenomenon on the hydrodynamic loads are also investigated.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"135 ","pages":"Article 104322"},"PeriodicalIF":3.4,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143847895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An interpolation-bounce-immersed boundary lattice Boltzmann method for fluid-structure-acoustic simulation applied to elastic airfoil trailing edge

IF 3.4 2区工程技术

Journal of Fluids and Structures Pub Date : 2025-04-18 DOI: 10.1016/j.jfluidstructs.2025.104324

Wen-zhi Liang , Pei-qing Liu , Jin Zhang , Qiu-lin Qu

{"title":"An interpolation-bounce-immersed boundary lattice Boltzmann method for fluid-structure-acoustic simulation applied to elastic airfoil trailing edge","authors":"Wen-zhi Liang , Pei-qing Liu , Jin Zhang , Qiu-lin Qu","doi":"10.1016/j.jfluidstructs.2025.104324","DOIUrl":"10.1016/j.jfluidstructs.2025.104324","url":null,"abstract":"<div><div>This paper presents a direct numerical simulation of fluid-structure-acoustic multi-physics coupling for an airfoil with an elastic trailing edge at the intermediate to high Reynolds numbers using the lattice Boltzmann method (LBM). When dealing with a moving boundary, a modified immersed boundary method (IBM) based on velocity correction and incorporating interpolated bounce back (IBB) is proposed. This method aims to capture the small pressure perturbations caused by solid vibrations through high-precision IBM for acoustic calculations at high Reynolds numbers. The method was validated by cantilever and NACA0012 airfoil cases, demonstrating its ability to simulate fluid-structure-acoustic coupling. A comparison between elastic trailing edge noise results with different elastic moduli and rigid trailing edge noise showed a decrease in low-frequency discrete tonal noise and an increase in high-frequency broadband noise, confirming the effectiveness of the method in simulating noise reduction with elastic trailing edges. Frequency domain analysis of the acoustic field results was conducted using DMD, confirming the physical nature of small perturbation waves, explaining the noise reduction mechanism, and validating the accuracy of the method in simulating small perturbation waves with elastic trailing edges.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"135 ","pages":"Article 104324"},"PeriodicalIF":3.4,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143844874","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Probability evaluation of blade flutter in a transonic compressor with inlet distortion using SSA-DBEN model 使用 SSA-DBEN 模型评估带有入口变形的跨音速压缩机叶片扑动的概率

IF 3.4 2区工程技术

Journal of Fluids and Structures Pub Date : 2025-04-15 DOI: 10.1016/j.jfluidstructs.2025.104318

Jingshan Wei, Zhidong Chi, Shimin Wang, Qun Zheng, Wei Yan, Bin Jiang

{"title":"Probability evaluation of blade flutter in a transonic compressor with inlet distortion using SSA-DBEN model","authors":"Jingshan Wei, Zhidong Chi, Shimin Wang, Qun Zheng, Wei Yan, Bin Jiang","doi":"10.1016/j.jfluidstructs.2025.104318","DOIUrl":"10.1016/j.jfluidstructs.2025.104318","url":null,"abstract":"<div><div>Inlet distortion significantly impacts the aeroelastic stability of aircraft engines, posing potential risks to their reliability and performance. Evaluating the probability of flutter in compressor blades is an effective approach to quantifying uncertain vibration characteristics and assessing blade aeroelastic stability. To improve modeling accuracy and computational efficiency in this analysis, a prediction method based on the sparrow search algorithm -deep extreme belief network (SSA-DEBN) model is proposed. The proposed method is evaluated through a case study involving the flutter probability assessment of a typical compressor rotor under inlet total pressure distortion. The results demonstrate that the aerodynamic modal damping ratio initially decreases and then increases as the wavelength of the inlet distortion decreases, reaching a minimum when the sinusoidal wave number of the distortion is two. Under inlet distortion conditions, the aerodynamic modal damping ratio of the compressor blade follows an approximate normal distribution, with a flutter reliability of 98.48 %. The primary factors influencing compressor blade flutter are rotational speed, inlet total temperature, vibration frequency, inlet total pressure, outlet static pressure, and distortion amplitude. The SSA-DEBN method has high accuracy and efficiency in the evaluation of compressor blade flutter failure mode by comparative analysis.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"135 ","pages":"Article 104318"},"PeriodicalIF":3.4,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143829387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Study on dynamic characteristics of coupled sloshing system with a movable baffle

IF 3.4 2区工程技术

Journal of Fluids and Structures Pub Date : 2025-04-10 DOI: 10.1016/j.jfluidstructs.2025.104320

Chenyi Wang , Changfang Zou , Xiaonan Yuan , Quanming Miao , Guijie Shi

引用次数: 0