Journal of Fluids and Structures最新文献

{"title":"Fluid-structure interaction analysis of an elastic surface-piercing propellers","authors":"M Pakian Bushehri ,&nbsp;MR Golbahar Haghighi ,&nbsp;P Malekzadeh ,&nbsp;E Bahmyari","doi":"10.1016/j.jfluidstructs.2024.104228","DOIUrl":"10.1016/j.jfluidstructs.2024.104228","url":null,"abstract":"<div><div>In high-speed planing craft, surface-piercing propellers (SPPs) operate semi-submerged in a two-phase air-water environment, facing stress and displacement from variable forces. In this paper, the fluid-structure interaction (FSI) of the SPP is investigated at immersion ratios of 30 %, 50 %, 70 % and 90 %, under low and high advance coefficients. A coupling of Reynolds-averaged Navier–Stokes equations (RANS) and elasticity theory are used to simulate fluid dynamics and the blade deformation with the multi-physics computational fluid dynamics software STAR-CCM+. The analysis is performed after several rotations of the SPPs at five different positions. The results show that at the advance coefficient of 0.4, a higher immersion ratio increases torque, thrust, efficiency, maximum stress, and maximum displacement. When the advance coefficient is equal to one, the efficiency, maximum stress, and maximum displacement remain constant for the immersion ratio above 50 %. The maximum displacement occurs at the blade tip, while maximum stress is at the trailing edge root. Most blade deformations happen where the blade enters the water, aligns perpendicularly with the water surface, and exits. The two-phase flow around the blade increases its displacement.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"132 ","pages":"Article 104228"},"PeriodicalIF":3.4,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142702009","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}

{"title":"Unsteady load mitigation through passive pitch","authors":"Yabin Liu ,&nbsp;Riccardo Broglia ,&nbsp;Anna M. Young ,&nbsp;Edward D. McCarthy ,&nbsp;Ignazio Maria Viola","doi":"10.1016/j.jfluidstructs.2024.104216","DOIUrl":"10.1016/j.jfluidstructs.2024.104216","url":null,"abstract":"<div><div>Mitigation of load fluctuations due to flow unsteadiness is critical in a broad range of applications, including wind/tidal turbines, and aerial/underwater vehicles. While the use of active control systems is an established practice in engineering, passive systems are not well understood, and the limits of their efficacy are yet to be ascertained. To this end, the present study aims to provide new insights into the effectiveness of passive pitching in the mitigation of lift fluctuations in the most demanding case of fast, high-amplitude variations of the free stream speed and direction. We perform fluid-structure interaction simulations of a two-dimensional free-to-pitch rigid foil. Our study reveals that the lift amplitude of the force fluctuations can be decreased by at least two-thirds through passive pitching. The efficacy of the unsteady load mitigation is only weakly dependent on the exact pitching axis location, and the optimal position is upstream and close to the axis of the foil. These results may inform the design of passive control systems of wind/tidal turbines and aerial/underwater vehicles and provide new insights into interpreting the control strategy of natural flyers such as insects and birds.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"131 ","pages":"Article 104216"},"PeriodicalIF":3.4,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142707336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Numerical investigation of fluid–structure interaction in a pilot-operated microfluidic valve","authors":"Ahmed Aissa-Berraies ,&nbsp;E. Harald van Brummelen ,&nbsp;Ferdinando Auricchio","doi":"10.1016/j.jfluidstructs.2024.104226","DOIUrl":"10.1016/j.jfluidstructs.2024.104226","url":null,"abstract":"<div><div>The present paper is concerned with numerical investigation of the performance of a pilot-operated control valve based on shape memory alloy actuation control. The valve under investigation can be integrated into miniaturized hydraulic systems and is developed to perform precise dispensing, mixing, or dosing tasks while being able to withstand relatively high pressure differences. The study evaluates the valve’s response under the current ON/OFF and the desired proportional control regimes using numerical methods for fluid–structure interaction. The computational model replicates the operation of the valve, which requires an understanding of the complex interactions between the fluid flow with the pressurized valve and the contact with the valve seat during the opening and closing processes. In addition, the model leverages advanced numerical techniques to overcome several complexities arising mainly from the geometrical, material, and contact nonlinearities, and to mitigate the shortcomings of the partitioned fluid–structure interaction approach. Several 3D fluid–structure-contact-interaction simulations are conducted to examine the valve’s structural and flow behavior under varying pressure conditions. Results indicate that the valve is adequate for ON/OFF actuation control but is susceptible to flow-induced vibrations during the proportional control regime that occurs due to the sharp pressure drop in the valve-seat gap and the ensuing Venturi effect, which counteract the opening of the main valve. The fluid–structure-interaction simulations provide insight into the mechanism underlying the flow-induced vibrations, which can serve to improve the design and enhance the performance of the valve in microfluidic applications.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"132 ","pages":"Article 104226"},"PeriodicalIF":3.4,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142702010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Flow-induced buckling of a bistable beam in uniform flow","authors":"Leixin Ma ,&nbsp;Wenyu Chen ,&nbsp;Ruosi Zha ,&nbsp;Alejandra Hernandez Escobar","doi":"10.1016/j.jfluidstructs.2024.104220","DOIUrl":"10.1016/j.jfluidstructs.2024.104220","url":null,"abstract":"<div><div>Recent developments in soft materials enable the design and manufacturing of bistable flexible structures. Their fast snap-through buckling mechanisms have been utilized to introduce fast locomotion. In this paper, we aim to understand the impact of fluid–structure interaction (FSI) on the dynamics of bistable structures. We report the numerical analysis of the snap-through buckling phenomena for several bistable flexible structures fixed at both ends. The motion is driven by the fluid loading of different flow speeds. The large deformation of the bistable structure is coupled with the incoming fluid flow via the Arbitrary Lagrangian–Eulerian (ALE) method. During the snap-through buckling process, the corresponding structural deformation patterns, hydrodynamic force distributions, and fluid patterns are discussed. Larger steady-state deformation is found for the bistable structure, compared to its mono-stable counterpart in the same flow condition. The Cauchy number is found to be the critical parameter affecting the buckling dynamics and dimensionless strain energy stored in the system. A prediction model for the dimensionless strain energy as a function of the Cauchy number is proposed. The hydrodynamic lift force generated by the fluid is found to increase the total strain energy of these bistable structures. The research could provide insight in designing morphable marine energy devices and lightweight bioinspired propulsion systems.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"131 ","pages":"Article 104220"},"PeriodicalIF":3.4,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142707335","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}

{"title":"Numerical analysis of glaze ice accretion on cables by considering the effects of typical in-plane vibrations","authors":"Chao Zhou ,&nbsp;Jiaqi Yin","doi":"10.1016/j.jfluidstructs.2024.104229","DOIUrl":"10.1016/j.jfluidstructs.2024.104229","url":null,"abstract":"<div><div>During the glaze icing process, cables experience vibrations due to the presence of aerodynamic forces, gravity, and other external forces. In most existing glaze icing models, the cables are assumed to be fixed, and water film is just run-down streams that do not reflect the complexity of the ice accretion process. To reveal the effects of in-plane motions of cable on the glaze icing process, two typical in-plane motions of aeolian vibration and galloping are taken into consideration and a mathematical water film-ice layer model is proposed for the first time. Based on the water film-ice layer model, ice accretion and water flow on the vibrating cables are studied, and key parameters of Collision Efficiency (CE), aerodynamic coefficients, and water film are evaluated by comparison with fixed cables. Moreover, by iterating the discretized mass and energy conservation equations with the computed aerodynamic coefficients, the effects of in-plane motions of the cable on water film and ice shapes are computed. The model then is verified with published experimental and numerical data. The results show that in-plane motions of the cables enlarge the windward face in dynamic forms which have certain effects on water film and ice shapes, and the model could provide accurate predictions of ice accretion.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"131 ","pages":"Article 104229"},"PeriodicalIF":3.4,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142707334","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}

{"title":"Stress relaxation and thermo-visco-elastic effects in fluid-filled slits and fluid-loaded plates","authors":"Erik García Neefjes ,&nbsp;David Nigro ,&nbsp;Raphaël C. Assier ,&nbsp;William J. Parnell","doi":"10.1016/j.jfluidstructs.2024.104219","DOIUrl":"10.1016/j.jfluidstructs.2024.104219","url":null,"abstract":"<div><div>In this paper, we theoretically analyse wave propagation in two canonical problems of interest: fluid-filled thermo-visco-elastic slits and fluid-loaded thermo-visco-elastic plates. We show that these two configurations can be studied via the same pair of dispersion equations with the aid of the framework developed in García Neefjes et al. (2022), which incorporates thermal effects. These two problems are further interrelated, since in the short wavelength limit (relative to the slit/plate width) the respective modes are governed by the same dispersion equation, commonly known as the Scholte–Stoneley equation. It is the Scholte-type modes that are mainly analysed in this paper. We illustrate results when the fluid is water, although the theory is valid for any Newtonian fluid. Both ‘hard’ and ‘soft’ solids are compared, with the emphasis being placed on the importance of thermo-viscoelastic effects, particularly when <em>stress relaxation</em> is considered. Two main recent works are discussed extensively, namely (Cotterill et al., 2018) for slits and (Staples et al., 2021) for loaded plates, both of which do not incorporate viscoelastic mechanisms. We show how the consideration of viscoelasticity can extend the results discussed therein, and explain the circumstances under which they arise.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"131 ","pages":"Article 104219"},"PeriodicalIF":3.4,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142658839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Numerical Prediction of Two-Dimensional Coupled Galloping and Vortex-Induced Vibration of Square Cylinders Under Symmetric/Asymmetric Flow Orientations","authors":"Yan Naung Aye,&nbsp;Narakorn Srinil","doi":"10.1016/j.jfluidstructs.2024.104215","DOIUrl":"10.1016/j.jfluidstructs.2024.104215","url":null,"abstract":"<div><div>This study presents an advanced numerical model for predicting a two-dimensional coupled galloping and vortex-induced vibration (VIV) in cross-flow and in-line directions of square cylinders under symmetric and asymmetric flow orientations. The present model combines the quasi-steady theory for the galloping with the nonlinear structure-wake oscillators simulating VIV, capturing the time-varying drag and lift hydrodynamic forces with the time-averaged and fluctuating components. By placing a flexibly mounted square cylinder in uniform flow at an initial angle of incidence, the cylinder is subject to instantaneous changes in the dynamic angle of attack accounting for relative flow-structure velocities. Modelling of such features in cross-flow and in-line directions for low and high mass ratio systems extends previous studies which have mostly focused on cross-flow responses of square cylinders with high mass ratios at a zero angle of incidence. New sets of empirical coefficients governing the drag and lift fluid forces for both the quasi-steady and wake oscillator approaches are introduced by calibrating with available experimental data in the literature, applicable to predict several flow-induced vibration phenomena under arbitrary flow-structure orientations. Mathematical criteria for the onset of two- and one-dimensional galloping instability are presented, verifying the likelihood of galloping occurrence. Parametric investigations are carried out to highlight the important effects of flow incidence angle, mass-damping ratio (Scruton number) and in-line response on the prediction of galloping and VIV in comparison with experimental results. By varying the reduced velocity parameter, the present model captures key qualitative features of the dominant galloping, interfering galloping-VIV and dominant VIV through the response amplitudes, mean drift displacements, oscillation frequencies, fluid force components and motion trajectories. Contributions from in-line responses are found to be meaningful for the interfering galloping-VIV system with a low mass-damping ratio and for an asymmetric flow orientation. The present model could be further calibrated and applied to other fluid-structure interaction applications with non-circular cross-sectional geometries under omnidirectional flow directions.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"131 ","pages":"Article 104215"},"PeriodicalIF":3.4,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142658838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"A three-dimensional nonlinear hydroelastic model for rectangular floating elastic plates and the examination on the peak frequency with maximum nonlinear response","authors":"S. Liang,&nbsp;Y. Gou,&nbsp;B. Teng","doi":"10.1016/j.jfluidstructs.2024.104217","DOIUrl":"10.1016/j.jfluidstructs.2024.104217","url":null,"abstract":"<div><div>The nonlinear interaction between nonlinear waves and a three-dimensional floating elastic plate is simulated by a time-domain nonlinear potential flow model. On the free surface, the 4th-order Runge-Kutta scheme with a semi-Lagrangian approach is adopted in the time-stepping process. The classical thin-plate theory is selected to simulate the motion of the elastic plate. The higher-order boundary element method (HOBEM) is employed to solve the corresponding boundary value problem at each time step. After validation of the present model, a particular frequency phenomenon is successfully observed in a three-dimensional hydroelastic problem, which shows that the second harmonic displacements at the centre point of the upwave side and downwave side of the elastic plate near a particular frequency are significantly large. In addition, the effect of the plate width on the particular frequency phenomenon is discussed.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"131 ","pages":"Article 104217"},"PeriodicalIF":3.4,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142658834","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}

{"title":"Numerical study of consecutive water entries in flowing water with twin spheres side-by-side","authors":"Xu Wang ,&nbsp;Jiazhen Zhao ,&nbsp;Xianzhong Tan ,&nbsp;Chao Qi ,&nbsp;Aochen Zhao ,&nbsp;He Li ,&nbsp;Ruisheng Sun ,&nbsp;Xujian Lyu","doi":"10.1016/j.jfluidstructs.2024.104218","DOIUrl":"10.1016/j.jfluidstructs.2024.104218","url":null,"abstract":"<div><div>A three-dimensional numerical model with six-degree-of-freedom is developed to simulate the side-by-side entry of twin spheres into flowing water. With the explicit volume of fluid (VOF) approach, the shear-stress transport (SST) <em>k-ω</em> model is adopted to delineate the turbulence structures within the flow, while the independent movements of the two spheres are tracked using advanced multi-overset mesh technology. The numerical findings elucidate the effects of water flow on cavity dynamics, flow field evolution, forces, and trajectories during consecutive sphere entries. Distinct flow field characteristics emerge depending on whether the trailing sphere enters the upstream side or downstream side. The flow-induced tilting of the first cavity results in a different scale of expansion of the trailing cavity with respect to that in quiescent water, diminishing the attractive force on the upstream-side sphere and enhancing it for the downstream-side sphere. As the lateral distance between the spheres increases, the forces of attraction and repulsion generated by the leading cavity become marginal in their effect on the trailing sphere's trajectory, particularly when compared with the impact force of the water flow.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"131 ","pages":"Article 104218"},"PeriodicalIF":3.4,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142658833","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}

{"title":"A new approach for spatio-temporal interface treatment in fluid–solid interaction using artificial neural networks employing coupled partitioned fluid–solid solvers","authors":"Farrukh Mazhar,&nbsp;Ali Javed","doi":"10.1016/j.jfluidstructs.2024.104200","DOIUrl":"10.1016/j.jfluidstructs.2024.104200","url":null,"abstract":"<div><div>Partitioned fluid–solid interaction (FSI) problems involving non-conforming grids pose formidable challenge in interface treatment, especially for information exchange, interface tracking, and field variable interpolation between solvers in both space and time. These demand special considerations for accurate and efficient simulations. This paper presents an application of artificial neural networks (ANN) for the interface treatment in a coupled FSI problem employing partitioned solvers. A shallow time-series ANN (nonlinear auto-regressive model with exogenous inputs, NARX) scheme is proposed to handle the exchange of Neumann/Dirichlet information at the coupling interface. This scheme involves two interface treatment models that were developed and analysed. The proposed models interpolate and transfer loads from the fluid to the solid domains, and conversely, displacements from the solid to the fluid domains between non-collocated grids. To validate this approach, we tested it on a 3D FSI problem, which involved damped oscillations of a flexible flap submerged in a fluid cavity. Adequately trained NARX interface models demonstrate reliable input–output mapping and accurate prediction of transient behaviour at the interface. Additionally, we explored the concept of reduced-order modelling (ROM) in the time domain. This allowed us to reduce the model’s complexity by half. Different training algorithms were evaluated to enhance the efficiency and performance of the proposed scheme. The study demonstrates that NARX networks trained with Bayesian Regularization (BR) and Levenberg–Marquardt (LM) algorithms exhibit the best accuracy, while the scaled conjugate gradient (SCG)-based training method provides better computational efficiency with acceptable accuracy. Overall, the NARX interface models provide precise performance and offer a viable potential for applications in FSI problems requiring accurate and faster computations.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"131 ","pages":"Article 104200"},"PeriodicalIF":3.4,"publicationDate":"2024-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142571756","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}