Journal of Fluids and Structures最新文献

{"title":"Hydrodynamic behavior of an offshore OWC power station under dam-break flows: Numerical and experimental study","authors":"Shiqi Pan ,&nbsp;Haochen Zhang ,&nbsp;Jing Geng ,&nbsp;Xuanlie Zhao","doi":"10.1016/j.jfluidstructs.2025.104426","DOIUrl":"10.1016/j.jfluidstructs.2025.104426","url":null,"abstract":"<div><div>The hydrodynamic behavior of a three-dimensional oscillating water column (OWC) device subjected to dam-break flow incidents was investigated using numerical and experimental methods. Load characteristics and flow field distributions were analyzed under various opening ratios of the air chamber and angles of incident flow. Numerical results were validated against experimental measurements of impact loads and water surface elevation at a 45° incident angle, and extended to six additional incident angles: 0°, 15°, 30°, 60°, 75°, and 90°. The peak impact load and air chamber pressure occurred at 90°, both decreasing as the incident angle varied to 0°. The peak horizontal resultant force decreased by 43.4 %, 55.3 %, and 65.9 % at 60°, 45°, and 30°, respectively, while peak air pressure decreased by up to 68 % at 0°. Loads on internal and external walls were of similar magnitudes, highlighting the importance of considering internal wall forces in structural design. Flow field analysis revealed complex flow contours and an inclined water surface inside the chamber, which became more pronounced as the incident angle decreased. Moreover, increasing the opening ratio of the air chamber significantly reduced peak impact loads and air pressure, especially in the range of 0 % to 3.5 %. However, larger opening ratios may reduce energy capture efficiency. Thus, selecting an appropriate opening ratio that balances load reduction with energy capture efficiency is crucial for OWC design.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"139 ","pages":"Article 104426"},"PeriodicalIF":3.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145159582","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":"Flow-induced vibration of twin-pipe model with varying mass and damping: A study using virtual physical framework","authors":"Jiawei Shen ,&nbsp;Shixiao Fu ,&nbsp;Xuepeng Fu ,&nbsp;Torgeir Moan ,&nbsp;Svein Sævik","doi":"10.1016/j.jfluidstructs.2025.104438","DOIUrl":"10.1016/j.jfluidstructs.2025.104438","url":null,"abstract":"<div><div>Flow-induced vibration (FIV) commonly occurs in rigidly coupled twin-pipe structures. However, the limited understanding of their FIV responses and hydrodynamic features presents a major challenge to the development of reliable engineering designs. To bridge this gap, the present study experimentally investigates the FIV characteristics of a rigidly coupled twin-pipe model with elastic support using a virtual physical framework (VPF), which enables flexible control of structural parameters during physical testing. A distinctive feature of twin-pipe structures is the presence of in-line hydrodynamic interactions and torsional moments arising from the rigid coupling. The in-line interaction is primarily compressive and becomes more pronounced as the mass ratio increases. The torsional moment coefficient exhibits a rise–fall trend with increasing reduced velocity <span><math><msub><mrow><mi>U</mi></mrow><mrow><mi>R</mi></mrow></msub></math></span> and stabilizes around 0.46 at low mass ratios. In addition, an “amplitude drop” phenomenon is observed near <span><math><mrow><msub><mrow><mi>U</mi></mrow><mrow><mi>R</mi></mrow></msub><mo>=</mo><mn>6</mn></mrow></math></span>, attributed to energy dissipation from the downstream pipe. The mass ratio significantly affects FIV amplitude, frequency, and hydrodynamic coefficients. As the mass ratio decreases, the synchronization region broadens and the hydrodynamic coefficients become more stable. Meanwhile, at mass ratio of 1.0, a “resonance forever” behavior is observed. Damping primarily suppresses FIV amplitude, with minimal impact on dominant frequency and hydrodynamic coefficients. These findings provide valuable insights into twin-pipe FIV mechanisms and support a scientific basis for future structural design optimization.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"139 ","pages":"Article 104438"},"PeriodicalIF":3.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145363699","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":"Active flow control of vertical-axis wind turbines: Insights from large-eddy simulation and finite-time resolvent analysis","authors":"Lucas Feitosa de Souza,&nbsp;Renato Fuzaro Miotto,&nbsp;William Roberto Wolf","doi":"10.1016/j.jfluidstructs.2025.104410","DOIUrl":"10.1016/j.jfluidstructs.2025.104410","url":null,"abstract":"<div><div>Active flow control is applied to improve the aerodynamic performance of a NACA0018 airfoil operating as a single-bladed vertical axis wind turbine (VAWT). Results computed by wall-resolved large-eddy simulations (LES) highlight the detrimental effects of the dynamic stall vortex (DSV) and trailing-edge vortex (TEV) on turbine efficiency, primarily through increased drag and energy loss. The proposed flow control strategy effectively delays flow separation and suppresses large-scale vortex formation, particularly at moderate actuation frequencies. The control parameters are grounded in bi-global stability and finite-time resolvent analyses. These techniques identify the excitation of coupling modes between shear layer and wake instabilities as a mechanism for promoting flow reattachment and preventing vorticity accumulation, ultimately leading to enhanced torque production. The control strategy is energy-efficient, consuming only 1% of the turbine’s output power while yielding substantial aerodynamic performance gains. These findings demonstrate the promise of physics-informed active flow control in mitigating dynamic stall and advancing the design of next-generation VAWTs.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"139 ","pages":"Article 104410"},"PeriodicalIF":3.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145109411","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":"An integrated computational method for vibroacoustic coupling analysis of an underwater structure with a floating raft and acoustic coatings","authors":"Yi-Ni Yang ,&nbsp;Hao Wang ,&nbsp;Ming-Song Zou ,&nbsp;Ye Liu ,&nbsp;Guo-Cang Sun ,&nbsp;Pei Li","doi":"10.1016/j.jfluidstructs.2025.104434","DOIUrl":"10.1016/j.jfluidstructs.2025.104434","url":null,"abstract":"<div><div>Based on three-dimensional sono-elasticity theory, this study proposes an integrated computational method for vibroacoustic coupling analysis of underwater structures equipped with a floating raft and acoustic coatings in finite water depth. The dynamic substructure method decomposes the complex system into three components: the main structure (including main hull, pedestal, bulkheads, and reinforcing ribs), vibration isolators, and the floating raft. Fluid-structure interaction is exclusively considered in the sono-elasticity coupling between the main structure and water, where the governing equations integrate modal superposition method, simple source boundary integral method, and mirror image virtual source method. The floating raft is modeled using the finite element method, its dynamic response is described by the modal superposition method. The isolators' vibration transmission characteristics are characterized using the four-terminal parameter method. Virtual modes are introduced to achieve dynamic coupling integration at connection boundaries. The impedance matrix model is derived to quantify the vibroacoustic transfer mechanism of acoustic coatings. The proposed methodology demonstrates significant advantages in structural optimization and acoustic performance analysis. Regardless of the modification of any component in the system, the overall response can be recalculated by updating the corresponding stiffness matrix, which substantially improves computational efficiency and engineering adaptability. The accuracy and engineering adaptability of the method are validated by numerical case studies and experimental results, and quantitative analyses are conducted on the influence of submergence depth and acoustic coating layout on acoustic radiation. This work provides theoretical foundations and engineering references for coordinated acoustic-stealth optimization of complex underwater structures.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"139 ","pages":"Article 104434"},"PeriodicalIF":3.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145269132","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":"Coupled poro-elastic behavior of hyper-elastic membranes","authors":"Alexander Gehrke,&nbsp;Zoe King,&nbsp;Kenneth S. Breuer","doi":"10.1016/j.jfluidstructs.2025.104411","DOIUrl":"10.1016/j.jfluidstructs.2025.104411","url":null,"abstract":"<div><div>This study investigates the coupled deformation and flow behavior of thin, hyper-elastic, porous membranes subjected to pressure loading. Using bulge test experiments, optical deformation measurements, and flow rate characterization, we analyze the structural and fluid dynamic responses of membranes with varying material stiffness and porosity patterns. A two-parameter Gent model accurately captures the hyper-elastic deformation, and local stretch analysis reveals non-uniform stretch distributions across the membrane. We find that membrane deformation is primarily governed by material stiffness and pressure, independent of porosity. Pore diameter scales linearly with local stretch, leading to a radial gradient of increasing pore size toward the membrane center. Flow rate scaling is characterized using a discharge coefficient, which accounts for both pore area expansion and pressure losses. Together, these results establish a unified framework that links structural deformation and flow performance in flexible porous membranes, providing robust scaling laws for the design of adaptive, bio-inspired flow-regulating systems.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"139 ","pages":"Article 104411"},"PeriodicalIF":3.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145050755","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":"Analytical solutions for the flexural–gravity and capillary–gravity wave resistances due to a steadily moving concentrated load","authors":"D.Q. Lu","doi":"10.1016/j.jfluidstructs.2025.104430","DOIUrl":"10.1016/j.jfluidstructs.2025.104430","url":null,"abstract":"<div><div>The interfacial flexural–gravity waves due to a concentrated load steadily moving on the thin elastic plate floating on the interface between two immiscible fluids of different densities are investigated analytically. The two inviscid fluids are assumed to be incompressible and homogeneous, and the motion be irrotational. The equation of motion for the plate, including the elastic force, the compressive force and the inertial force, is imbedded in the dynamic boundary conditions on the interface. Based on the linear potential theory for small-amplitude waves, the integral solutions for the interfacial wave profiles and wave resistances are derived by the Fourier transform. The dispersion relation and the exact solutions for the wave numbers are explicitly deduced. It is found the wave dynamical behaviors depend on the relation between the moving speed and the minimal phase speed. The maximal allowable value for the compressive force is obtained, at which the minimal phase speed is zero and the wave motion can be stimulated with any nonzero moving speed of the load due to the presence of compressive stress in the plate. The effects of the flexural rigidity and the fluid density ratio are also explored. The solutions for the capillary–gravity wave can readily be recovered by discarding the elastic force in the present formulation.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"139 ","pages":"Article 104430"},"PeriodicalIF":3.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145222498","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":"Dynamics and energies of a wall-clamped flexible membrane in two different cross-flows","authors":"Zhiwei Liu ,&nbsp;Hanfeng Wang ,&nbsp;Jiaxuan Li ,&nbsp;Ziqiang Zhang ,&nbsp;Hui Tang","doi":"10.1016/j.jfluidstructs.2025.104436","DOIUrl":"10.1016/j.jfluidstructs.2025.104436","url":null,"abstract":"<div><div>In order to provide useful guidelines for optimizing piezoelectric energy harvesting designs under near-wall conditions, we experimentally investigate and compare the dynamics and energies of a wall-clamped flexible membrane (FM) in two different cross-flows, i.e., a separated flow induced by a forward-facing step (FFS) and a boundary layer (BL) flow, aiming at revealing the combined effects of the incoming flow and wall contact on flapping dynamics. Four dynamic modes were identified in both the FFS and BL cases by varying flow velocity and FM length: quasi-steady, regular-flapping, tip-contact, and body-contact modes. In the FFS cases, the recirculation zone induced by the step prevents the FM from lodging, whereas in the BL cases, the FM exhibits suppressed amplitudes and near-wall flapping behavior. The evolution of the two contact modes was examined in details, and the variations in contact time and contact distance during the transition between these two modes were quantitatively evaluated. Three-dimensional effects manifest differently in each case, with the FFS showing primarily spanwise bending and the BL case exhibiting pronounced twisting that impacts flapping stability. Energy analysis further reveals that, at high flow velocity, the FM’s kinetic energy dominates over elastic strain energy, with significant energy dissipation occurring during wall contact.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"139 ","pages":"Article 104436"},"PeriodicalIF":3.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145269134","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":"Exact and explicit wavenumbers and closed-form solutions of the Ye equation for water wave propagation over L-type bed terrains","authors":"Huan-Wen Liu","doi":"10.1016/j.jfluidstructs.2025.104441","DOIUrl":"10.1016/j.jfluidstructs.2025.104441","url":null,"abstract":"<div><div>The differential equations governing water surface gravity wave motion over uneven seabeds are generally difficult to be solved analytically. For the original Laplace equation together with appropriate boundary and radiation conditions, there appears to be only one closed-form solution, called Roseau’s solution. For the depth-averaged equations such as the mild-slope type equation, the Ye equation, and the Boussinesq equation, the closed-form solutions are rare because the wavenumber has never been solved exactly from the Airy dispersion equation since it was derived by Airy in 1841. In this paper, Airy dispersion equation is exactly solved for linear surface gravity waves propagating over a cluster of special terrains, called the L-type seabeds. Furthermore, based on the explicit Airy wavenumbers, closed-form solutions to the Ye equation for wave reflection by a trapezoidal hump/trench with the two slopes being the L-type terrains are successfully constructed. To this author’s knowledge, this is the first group of closed-form solutions to depth-averaged wave equations in the whole wave range from shallow-water waves to deep-water waves.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"139 ","pages":"Article 104441"},"PeriodicalIF":3.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145321276","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":"Progressive flutter prediction using flight data with limited sensors and actuators","authors":"John T. Kim","doi":"10.1016/j.jfluidstructs.2025.104372","DOIUrl":"10.1016/j.jfluidstructs.2025.104372","url":null,"abstract":"<div><div>In this work, the flutter prediction theory and method originally developed by the author based on the dynamic eigen decomposition technique are modified for applications to flight flutter simulation and testing of airplanes. Towards this end, frequency responses to control surface excitations are processed at subcritical conditions and the dynamic eigenvalues calculated herein are extrapolated to higher dynamic pressures. To obtain enough responses, the flight test is repeated progressively such that the data set is augmented as more responses are added. By using a recursive formula that relates frequency responses at different dynamic pressures it is possible to expand the columns in the transfer function matrix by integer multiples, thus making the measurements and the excitations equal in number. For demonstration of the new methodology, a tapered wing with four flaps is modeled using ten flexible wing modes and four rigid flap modes. Theodorsen’s theory accounting for motion of the control surfaces is employed for unsteady aerodynamics. It is shown that the proposed scheme as applied to the simulated flight data not only results in extremely accurate predictions of flutter but also is procedurally compatible with the present-day practices, e.g., aeroelastic damping extrapolation, providing a viable option for flutter prediction based on flight test data.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"138 ","pages":"Article 104372"},"PeriodicalIF":3.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144722455","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":"Hydroelastic analysis of oblique wave interaction with submerged L-shaped Jarlan-type breakwater","authors":"Biman Sarkar ,&nbsp;Soumen De ,&nbsp;Chia-Cheng Tsai ,&nbsp;Tai-Wen Hsu","doi":"10.1016/j.jfluidstructs.2025.104389","DOIUrl":"10.1016/j.jfluidstructs.2025.104389","url":null,"abstract":"<div><div>This study explores the hydroelastic response of surface waves interacting with a submerged L-shaped Jarlan-type breakwater system, featuring a perforated front plate and a rigid rear plate attached above the left edges of two solid rectangular blocks to create an innovative L-shaped configuration. The entire breakwater system is submerged below a water surface that is covered by an infinite, continuous thin elastic plate of uniform thickness, governed by the Euler–Bernoulli beam theory. Distinctively, the present work accurately accounts for the submergence depth of the rectangular block within L-shaped configuration, along with the influence of the elastic plate’s thickness—factors often neglected in previous studies. This important consideration reveals new insights into wave–structure interactions under an elastic sheet, motivating the present analysis within the framework of linearized water wave theory. To analyze the wave interaction, the associated boundary value problem is reformulated into a system of integral equations. These equations are then solved approximately using a multi-term Galerkin method, which proves highly effective in handling the inherent singularities: specially, the square-root singularities at the submerged tips of the thin plates and the one-third singularities at the sharp corners of the solid rectangular blocks. A comprehensive numerical investigation is carried out to examine the influence of key physical parameters on the reflection and transmission coefficients, energy loss, horizontal wave forces acting on each plate and the surface displacement under various wave conditions. Graphical analyses further reveal that the present breakwater system offer a significant advantage over the traditional Jarlan-type configuration (as studied by Liu et al. (2014)). Both the perforated front plate and the rigid rear plate experience notably reduced horizontal wave forces compared to those in the conventional Jarlan-type model, highlighting the improved efficiency and structural stability of the proposed design.</div></div>","PeriodicalId":54834,"journal":{"name":"Journal of Fluids and Structures","volume":"138 ","pages":"Article 104389"},"PeriodicalIF":3.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144757724","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}