Journal of Fluids and Structures最新文献_第2页

Fluid-structure interaction analysis for yaw stability and propulsion of the biomimetic fish considering recoil motion 考虑后坐运动的仿生鱼的偏航稳定性和推进力流固耦合分析

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2026-04-01 Epub Date: 2026-01-15 DOI: 10.1016/j.jfluidstructs.2026.104518

Minghao Zhou , Ming Luo , Zhigang Wu , Chao Yang

Body and caudal fin propulsion is the primary mode of swimming for most fish species. Although the associated hydrodynamics have garnered increasing attention in recent years, previous studies have considered the fish body to be fixed or part of the travelling wave motion, neglecting the effect of passive recoil motion. In this paper, an efficient fluid-structure interaction analysis method is employed to investigate a three-dimensional flying fish model featuring a rigid head, prescribed-motion tail, and flexible caudal fin. A strongly coupled analysis framework, integrating flexible multi-body dynamics and the vortex particle method, is utilized. By permitting free yaw rotation of the fish body, this study investigates the impact of multiple kinematic parameters and caudal fin flexibility on the yaw stability and propulsion performance when incorporating recoil motion into the simulations. The results indicate that although increasing either the frequency or amplitude of the oscillation enhances the thrust force, a rise in frequency notably improves stability, whereas an increase in amplitude reduces it. Moreover, the moderately flexible caudal fin effectively mitigates recoil motion and enhances propulsion performance, but reduces yaw stability during extended cruising.

身体和尾鳍推进是大多数鱼类游泳的主要方式。尽管近年来相关的流体力学得到了越来越多的关注，但以往的研究都认为鱼体是固定的或行波运动的一部分，而忽略了被动后坐力运动的影响。本文采用一种高效的流固耦合分析方法，对具有刚性头部、规定运动尾部和柔性尾鳍的三维飞鱼模型进行了研究，采用了一种结合柔性多体动力学和涡旋粒子法的强耦合分析框架。通过允许鱼体自由偏航旋转，本研究在将后坐力运动纳入模拟时，研究了多种运动学参数和尾鳍柔韧性对偏航稳定性和推进性能的影响。结果表明，虽然增加振动频率或振幅都能增强推力，但频率的增加明显提高了稳定性，而振幅的增加则降低了稳定性。此外，适度灵活的尾鳍有效地减轻了后坐力运动，提高了推进性能，但在长时间巡航时降低了偏航稳定性。

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引用次数: 0

Wave-current-floating body interactions: Experiments and modelling 波-流-浮体相互作用：实验和模型

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2026-04-01 Epub Date: 2026-01-11 DOI: 10.1016/j.jfluidstructs.2025.104498

Masoud Hayatdavoodi , Shuijin Li

The interaction of combined waves and current with floating bodies is studied by conducting laboratory experiments and by developing theoretical models. The laboratory experiments are conducted in a wave-current tank using two floating cylinders with circular and square waterplane areas. Both freely floating and moored conditions are considered. Two theoretical models are developed to study wave-body and wave-current-body interactions: one based on the computational fluid dynamics and the other following the linear wave-current diffraction theory using the Green function method. Results from these models are compared with laboratory measurements for a range of wave and wave-current conditions. The study analyses the effect of ambient current on the wave-induced motions of floating bodies and evaluates how well the models capture the wave-current-body interactions. Additionally, the effect of the square cylinder’s sharp edges on wave-current-body interactions is analysed in comparison to the circular cylinder, along with the models’ capability to capture these effects. It is observed that the presence of the current not only causes significant drift of the freely floating cylinders, but also affects their surge and pitch oscillations, while having no notable effect on heave motion. For the conditions considered, the linear theory based on the Green function method provides overall good predictions of the floating bodies’ responses at a significantly lower computational cost compared to the computational fluid dynamics model.

通过室内实验和建立理论模型，研究了波浪和水流与浮体的相互作用。实验在波浪流槽中进行，采用圆形和方形水面面积的两个浮柱。自由浮动和系泊条件都被考虑。建立了两个理论模型来研究波-体和波-流-体相互作用：一个基于计算流体力学，另一个基于格林函数方法的线性波-流衍射理论。这些模型的结果与一系列波浪和波流条件下的实验室测量结果进行了比较。本研究分析了环境电流对浮体波浪运动的影响，并评估了模型如何很好地捕捉波浪-流-体相互作用。此外，与圆形圆柱体相比，分析了方形圆柱体的尖锐边缘对波流体相互作用的影响，以及模型捕捉这些影响的能力。观察到，电流的存在不仅使自由漂浮的气缸产生明显的漂移，而且影响其喘振和俯仰振荡，而对升沉运动没有显著影响。对于所考虑的条件，基于格林函数方法的线性理论与计算流体动力学模型相比，以显著降低的计算成本提供了总体上较好的浮体响应预测。

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引用次数: 0

Stable fluid-rigid body interaction algorithm using the direct-forcing immersed boundary method (DF-IBM) 基于直接强迫浸入边界法的稳定流体-刚体相互作用算法（DF-IBM）

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2026-04-01 Epub Date: 2026-01-05 DOI: 10.1016/j.jfluidstructs.2025.104496

Elias Farah , Abdellatif Ouahsine , Patrick G. Verdin , Badr Kaoui

The direct-forcing immersed boundary method (DF-IBM) algorithm previously developed by the authors is extended by coupling the Navier-Stokes equations with the Newton-Euler equations for rigid body dynamics within the DF-IBM framework. This coupling broadens the applicability of the previous development, from stationary or prescribed motion to flow-induced (free) motion cases. To address fluid-rigid body interactions under a partitioned approach, an implicit coupling algorithm is developed to handle strongly coupled interface conditions. Stability and convergence issues, particularly stemming from critical solid-fluid density ratios and from the rigid body approximation of internal mass effects in rotational dynamics, are mitigated using a fixed relaxation technique for the rigid body kinematics to ensure numerical robustness. Additionally, the proposed algorithm leverages the previously developed DF-IBM formulation and the predictor-corrector strategy of the pressure implicit with splitting of operators (PISO) algorithm by omitting the momentum predictor step and the costly corrector loops from the implicit iterations. The method is validated against several benchmark cases, demonstrating robustness, stability, and efficiency in capturing complex fluid-rigid body interactions across a range of challenging scenarios.

通过在DF-IBM框架内将刚体动力学的Navier-Stokes方程与Newton-Euler方程耦合，对作者先前开发的直接强迫浸入边界法（DF-IBM）算法进行了扩展。这种耦合扩大了先前开发的适用性，从固定或规定运动到流诱导（自由）运动情况。为了在分区方法下处理流体-刚体相互作用，提出了一种隐式耦合算法来处理强耦合界面条件。稳定性和收敛问题，特别是源于临界固流密度比和旋转动力学中内部质量效应的刚体近似，使用刚体运动学的固定松弛技术来缓解，以确保数值稳健性。此外，该算法利用先前开发的DF-IBM公式和压力隐式算子分裂（PISO）算法的预测-校正策略，省去了隐式迭代中的动量预测步骤和代价高昂的校正循环。该方法通过几个基准案例进行了验证，证明了在一系列具有挑战性的场景中捕获复杂流体-刚体相互作用的鲁棒性、稳定性和效率。

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引用次数: 0

Mechanism and regulation of silicone oil fluid volume on the stick-slip behavior of PDMS sponges 硅油液量对PDMS海绵粘滑行为的影响机理及调控

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2026-04-01 Epub Date: 2026-01-06 DOI: 10.1016/j.jfluidstructs.2026.104501

Rongxin Chen , Hui Zhong , Bozhan Hai , Qingrui Song , Wei Zhang , Guofu Lian

Stick-slip behavior during friction is a critical factor contributing to the degradation of PDMS material performance. To mitigate this phenomenon, this study investigates the effects of silicone oil with varying parameters on the frictional and mechanical properties of PDMS sponges. Friction experiments were conducted by introducing silicone oil fluids, and the influence of silicone oil on the friction coefficient and stick-slip behavior was analyzed. Additionally, the nominal modulus of elasticity of PDMS sponges was measured to explore the interrelationship among elasticity, friction coefficient, and stick-slip behavior. The results demonstrate that as the viscosity of silicone oil increases, the stick-slip time (∆t) of PDMS sponge decreases, the difference between static and kinetic friction coefficients (∆μ) diminishes, and the modulus of elasticity of PDMS sponge increases. High-viscosity silicone oil effectively reduces both stick-slip behavior and the friction coefficient of PDMS sponge. At constant viscosity, an increase in the volume of silicone oil leads to a reduction in the friction coefficient of PDMS sponge but simultaneously enhances the likelihood of stick-slip behavior while decreasing the nominal modulus of elasticity. By controlling the liquid parameters of silicone oil, the friction coefficient and stick-slip behavior of PDMS sponges can be modulated. This study explores the formation mechanism of the viscous-slip behavior and proposes a method to control the viscous-slip behavior by different liquids. This can provide theoretical guidance for the regulation of viscous-slip behavior in other polymers.

摩擦过程中的粘滑行为是导致PDMS材料性能退化的关键因素。为了缓解这一现象，本研究研究了硅油不同参数对PDMS海绵摩擦和力学性能的影响。通过引入硅油流体进行摩擦实验，分析了硅油对摩擦系数和粘滑性能的影响。此外，测量了PDMS海绵的名义弹性模量，以探索弹性，摩擦系数和粘滑行为之间的相互关系。结果表明：随着硅油粘度的增加，PDMS海绵的粘滑时间（∆t）减小，静摩擦系数与动摩擦系数之差（∆μ）减小，海绵的弹性模量增大；高粘度硅油能有效降低PDMS海绵的粘滑性能和摩擦系数。在一定粘度下，硅油体积的增加导致PDMS海绵的摩擦系数降低，但同时增加了粘滑行为的可能性，同时降低了公称弹性模量。通过控制硅油的液体参数，可以调节PDMS海绵的摩擦系数和粘滑性能。本研究探讨了粘滑行为的形成机理，并提出了不同液体控制粘滑行为的方法。这可以为其它聚合物的粘滑行为调控提供理论指导。

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引用次数: 0

Dynamics of elongated microswimmers in a square-tube flow 方管流动中细长微游泳体的动力学

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2026-04-01 Epub Date: 2026-01-09 DOI: 10.1016/j.jfluidstructs.2025.104499

Yuxiang Ying, Geng Guan, Tongxiao Jiang, Amin Ullah, JianZhong Lin

Microswimmers exhibit remarkable dynamic properties in fluid environments, making them important for advancing the fields of fluid mechanics and biophysics. In this study, we extended the classical squirmer model to an ellipsoidal geometry and investigated its swimming behavior in a three-dimensional square-tube flow. The results were compared with those of a spherical microswimmer. By systematically varying key parameters, including the self-propulsion strength (α), swimming type factor (β), chirality factor (χ), and flow field Reynolds number (Re_m), we identified five distinct swimming modes: near-wall helical motion, near-center helical motion, steady linear motion, zigzag motion, and near-wall double-helical motion, in which the microswimmer exhibited two different swimming directions (upstream and downstream). The results show that chirality and geometric anisotropy significantly influenced the swimming behavior of the microswimmer. The formation of swimming modes is also related to the pressure distribution between the microswimmer and the wall. In addition, the swimming velocity and helical frequency of the microswimmer increased with increasing α or Re_m; however, the increase in the Reynolds number did not change the swimming mode of the microswimmer. Our research is expected to promote the understanding of the motion characteristics of active matter in dynamic flows and provide valuable insights into the design of efficient and controllable artificial microswimmers for biomedical and environmental applications.

微游泳者在流体环境中表现出显著的动态特性，对推进流体力学和生物物理学领域具有重要意义。在本研究中，我们将经典的蠕动模型扩展到椭球体，并研究了它在三维方管流中的游动行为。结果与球形微游泳者的结果进行了比较。通过系统地改变自推进强度（α）、游泳类型因子（β）、手性因子（χ）和流场雷诺数（Rem）等关键参数，确定了微游泳者的五种不同的游泳模式：近壁螺旋运动、近中心螺旋运动、稳定直线运动、之字形运动和近壁双螺旋运动，在这些模式下微游泳者表现出两种不同的游泳方向（上游和下游）。结果表明，手性和几何各向异性对微游泳者的游泳行为有显著影响。游泳模式的形成还与微游泳者与壁面之间的压力分布有关。此外，微游泳者的游泳速度和螺旋频率随α或Rem的增加而增加；然而，雷诺数的增加并没有改变微游泳者的游泳方式。我们的研究有望促进对动态流动中活性物质运动特性的理解，并为生物医学和环境应用中高效可控的人工微游泳者的设计提供有价值的见解。

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引用次数: 0

Mathematical modeling of nonlinear coupled along- and across-wind aeroelastic responses in tall slender structures with square section 方形截面高细长结构非线性耦合顺、横风气动弹性响应的数学建模

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2026-04-01 Epub Date: 2026-01-15 DOI: 10.1016/j.jfluidstructs.2026.104514

Shuai Huang , Qingshan Yang , Zhanfang Liu , Haohong Li , Wenshan Shan , Chen Li

Tall slender structures are prone to aeroelastic instability, such as vortex resonance and galloping, in which the along-wind response is often neglected in conventional analyses. Recent experimental studies, however, have shown that near the wind speed corresponding to across-wind resonance, the along-wind vibration becomes coupled with the across-wind vibration, resulting in a significant amplification of the along-wind response and a reduction of the across-wind response. The underlying nonlinear self-excited forces driving this coupled behavior remain insufficiently understood. This study proposes a method for identifying the self-excited forces of tall slender structures accounting for along- and across-wind coupling. Displacement responses in both directions were measured through wind tunnel tests using a pivot model, followed by complex modal parameter identification. It was found that the mode with a frequency close to the across-wind natural frequency predominantly governs the structural response. A mathematical model was then established to predict coupled vibrations and to identify nonlinear self-excited forces. A generalized Van der Pol-type damping model was employed to capture the amplitude dependence of the first-mode damping ratio. Finally, the prediction model and the self-excited force identification method were validated against experimental results. The proposed approach provides a theoretical framework for analyzing aeroelastic instability of tall slender structures with along- and across-wind coupling effects.

细长高架结构容易发生涡共振和驰动等气动弹性失稳，而在这些失稳中，沿风响应在传统分析中往往被忽略。然而，最近的实验研究表明，在横风共振对应的风速附近，顺风振动与横风振动耦合，导致顺风响应明显放大，横风响应减弱。驱动这种耦合行为的潜在非线性自激力仍然没有得到充分的了解。本文提出了一种考虑顺风和横风耦合的高细长结构自激力识别方法。采用主轴模型进行风洞试验，测量了两个方向的位移响应，然后进行了复杂模态参数辨识。研究发现，接近横风固有频率的模态主导结构响应。然后建立数学模型来预测耦合振动和识别非线性自激力。采用广义Van der pol型阻尼模型来捕捉第一模态阻尼比的幅值依赖性。最后，根据实验结果对预测模型和自激力识别方法进行了验证。该方法为分析具有顺风和横风耦合效应的高细长结构的气动弹性失稳提供了理论框架。

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引用次数: 0

Hydrodynamic study of a novel surface standing-and-turning behavior of robotic dolphins 一种新型机器人海豚表面站立转身行为的流体动力学研究

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2026-04-01 Epub Date: 2026-01-12 DOI: 10.1016/j.jfluidstructs.2026.104512

Ming Lei , Qingyuan Gai , Tongfu Zou , Dan Xia

To enhance the surface operation capabilities of traditional bionic underwater vehicles (BUVs) in, this study explored the feasibility of dolphins performing cross-medium standing-and-turning (SAT) behavior on the water surface from a hydrodynamics perspective. A physical model and computational model of the robotic dolphin’s surface SAT behavior were established. After numerous attempts, the surface SAT behavior of the robotic dolphin was successfully replicated through coordinated movements of the body, caudal fin, and pectoral fins, and the quantitative relationship between controllable parameters and hydrodynamic performance was investigated. By combining data analysis and flow field distribution patterns, the underlying physical mechanisms of the robotic dolphin’s surface SAT behavior were revealed. The results indicate that the turning trajectory of SAT behavior exhibits a circular characteristic, and the turning radius can be adjusted by modifying the kinematic parameters. Additionally, when the movement parameters of the body and caudal fin are fixed, and the phase difference between the two pectoral fins is T/2, the robotic dolphin achieves optimal turning maneuverability, with a maximum turning speed of 1.69 rad/s and a turning efficiency of up to 45.5%. Notably, by optimizing kinematic parameters, the robotic dolphin achieves cross-medium in-situ turning with exceptionally high maneuverability, which is indeed a very valuable discovery. The findings provide a cross-medium fluid dynamics explanation for the development of BUVs with dual underwater/surface operating capabilities.

为了提高传统仿生水下航行器（buv）的水面操作能力，本研究从水动力学角度探讨了海豚在水面上进行跨介质站立转向（SAT）行为的可行性。建立了机械海豚表面SAT行为的物理模型和计算模型。经过多次尝试，通过身体、尾鳍和胸鳍的协调运动，成功复制了机器海豚的表面SAT行为，并研究了可控参数与水动力性能之间的定量关系。通过数据分析和流场分布模式相结合，揭示了机器海豚表面SAT行为的潜在物理机制。结果表明，SAT行为的转弯轨迹呈现圆形特征，并且可以通过改变运动学参数来调节转弯半径。另外，当身体和尾鳍运动参数固定，胸鳍相位差为T/2时，机器海豚的转弯机动性达到最佳，最大转弯速度为1.69 rad/s，转弯效率高达45.5%。值得注意的是，通过优化运动学参数，机器人海豚实现了跨介质原地转弯，具有极高的机动性，这确实是一个非常有价值的发现。这些发现为具有水下/水面双重操作能力的buv的发展提供了跨介质流体动力学解释。

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引用次数: 0

A CNN-BiLSTM-ATT hybrid model for predicting wind pressure on saddle-shaped membrane structures 鞍形膜结构风压预测的CNN-BiLSTM-ATT混合模型

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2026-04-01 Epub Date: 2026-01-22 DOI: 10.1016/j.jfluidstructs.2026.104511

Fang-Jin Sun , Qi-Qi Chen , Da-Ming Zhang

Membrane structures are extensively used in modern architecture due to their lightweight properties, high strength, and design versatility. However, accurately predicting wind pressure remains a persistent challenge in structural safety design, owing to their complex pressure distribution and pronounced flow-field sensitivity.To address this challenge, this study proposes a CNN-BiLSTM-ATT deep learning model for high-precision wind pressure prediction on saddle-shaped membrane structures. The model integrates convolutional neural networks for spatial feature extraction, bidirectional LSTM for temporal modeling, and an attention mechanism for adaptive feature weighting. Its performance is evaluated against a BiLSTM-ATT benchmark under various wind angles (0^∘ and 45^∘) at key measurement points. Experimental results show excellent predictive accuracy, with root mean square error reduced by 57%–78% and a maximum coefficient of determination (R²) of 0.9919, significantly outperforming the benchmark.The proposed model effectively captures both the spatiotemporal features of wind pressure data and its non-Gaussian statistical properties, while revealing the underlying physics of complex flow fields. This provides a robust and efficient approach for wind pressure prediction and structural safety design, significantly improving the wind resistance performance and engineering quality of membrane structures.

膜结构由于其轻量化、高强度和设计通用性而广泛应用于现代建筑。然而，由于风压分布复杂且流场敏感，如何准确预测风压是结构安全设计中一个长期存在的挑战。为了解决这一挑战，本研究提出了一种CNN-BiLSTM-ATT深度学习模型，用于鞍形膜结构的高精度风压预测。该模型集成了用于空间特征提取的卷积神经网络、用于时间建模的双向LSTM和用于自适应特征加权的注意机制。它的性能是根据BiLSTM-ATT基准在不同的风角（0°和45°）下在关键测量点进行评估的。实验结果表明，该方法具有良好的预测精度，均方根误差降低了57% ~ 78%，最大决定系数（R2）为0.9919，显著优于基准方法。该模型有效地捕捉了风压数据的时空特征及其非高斯统计特性，同时揭示了复杂流场的潜在物理特性。这为膜结构的风压预测和结构安全设计提供了可靠有效的方法，显著提高了膜结构的抗风性能和工程质量。

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引用次数: 0

An Encoder-Decoder analysis framework for the characterization of nonlinear aerodynamic forces and limit cycle flutter of bluff bodies 钝体非线性气动力和极限环颤振特性的编码器-解码器分析框架

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2026-04-01 Epub Date: 2026-01-23 DOI: 10.1016/j.jfluidstructs.2026.104520

Hanyu Mei , Hao Hu , Bo Wu , Pin Ye , Yuxuan Yan , Haili Liao

This study proposes an Encoder-Decoder analytical framework that balances minimal experimental input with high identification accuracy. Relying solely on free vibration response time histories, the framework enables the retrieval of full-process nonlinear aerodynamic forces (NAF) and the quantification of limit cycle oscillations (LCO) for bluff-body sections. Using a 5:1 rectangular section as a case study, section model tests involving synchronized vibration and pressure measurements under free vibration were conducted to capture the system’s surface pressure distribution and nonlinear flutter responses. The single-degree-of-freedom (SDOF) torsional flutter and vertical-torsion coupled two degrees of freedom (2DOF) flutter behavior of the section were examined in detail. Subsequently, the flutter responses are treated as observation states fed into an Encoder composed of neural networks to model the hidden variable (e.g., NAF). A Decoder based on the Newmark-β method is then employed to reconstruct the nonlinear flutter response by decoding the encoded NAF. Through iterative computation of the encoding and decoding processes over successive time steps, gradient descent methods (GDM) are introduced to minimize the error between predicted and observed responses, thereby establishing a complete closed-loop training procedure for NAF identification and LCO prediction. The effectiveness and accuracy of the framework in characterizing the nonlinear aerodynamic behavior of bluff bodies are validated through distinct dynamic system wind tunnel experiments, considering both transient NAF and LCO amplitudes.

本研究提出一个编码器-解码器分析框架，平衡最小的实验输入与高识别精度。仅依靠自由振动响应时间历史，该框架可以检索全过程非线性气动力（NAF）和崖体部分的极限环振荡（LCO）的量化。以5:1矩形截面为例，进行了自由振动下的截面模型试验，包括同步振动和压力测量，以捕捉系统的表面压力分布和非线性颤振响应。详细研究了该截面的单自由度扭转颤振和垂直扭转耦合两自由度颤振特性。随后，将颤振响应作为观测状态输入到由神经网络组成的编码器中，对隐变量（如NAF）进行建模。然后采用基于Newmark-β方法的解码器对编码后的NAF进行解码，重构非线性颤振响应。通过连续时间步长的编码和解码过程的迭代计算，引入梯度下降法（GDM）来最小化预测响应与观测响应之间的误差，从而建立一个完整的闭环训练过程，用于NAF识别和LCO预测。在考虑瞬态NAF和LCO振幅的情况下，通过不同的动力系统风洞实验验证了该框架表征钝体非线性气动行为的有效性和准确性。

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引用次数: 0

Interplay between shock-induced panel flutter and the Kelvin-Helmholtz instability in laminar flow 层流中激波诱导板颤振与开尔文-亥姆霍兹不稳定性的相互作用

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2026-04-01 Epub Date: 2026-01-13 DOI: 10.1016/j.jfluidstructs.2025.104497

James L. Fields , Anshul Suri , Caleb J. Barnes , Jack J. McNamara , Datta V. Gaitonde

This paper investigates the interplay between the Kelvin-Helmholtz (K-H) instability, aeroelastic flutter, and laminar shock-boundary layer interactions. The coupled system is studied by performing modal-based analyses over distinct phases of the aeroelastic response. The initial response is comparable to classical panel flutter and is dominated by first- and second-mode panel deflections. Over time, a frequency lock-in occurs between K-H waves in the flow and high-order modes in the panel, resulting in mutual growth. The growth of the K-H instability leads to a period of cascading frequency and modal content in which energy is channeled into several discrete oscillating panel modes. It is shown through a bispectral mode decomposition that the frequency cascade is driven by nonlinear interactions between panel modes. The asymptotic state of the aeroelastic system is classified as a multi-mode limit cycle oscillation and exhibits a traveling wave flutter. The time-mean flow field exhibits reductions in both the separation bubble volume and downstream boundary layer thickness in the presence of the fluttering panel, supporting the notion of fluid-structure interaction as a means for passive flow control of SBLIs.

本文研究了开尔文-亥姆霍兹（K-H）不稳定性、气动弹性颤振和层流激波-边界层相互作用之间的相互作用。通过对气动弹性响应的不同阶段进行基于模态的分析来研究耦合系统。初始响应与经典板颤振相当，主要受一模和二模板挠度的影响。随着时间的推移，流动中的K-H波和面板中的高阶模态之间发生频率锁定，导致相互增长。K-H不稳定性的增长导致了一段时间的级联频率和模态含量，在此期间能量被引导到几个离散的振荡面板模态。通过双谱模式分解表明，频率级联是由面板模式之间的非线性相互作用驱动的。气动弹性系统的渐近状态为多模态极限环振荡，表现为行波颤振。在颤振板存在的情况下，时间平均流场表现出分离泡体积和下游边界层厚度的减小，这支持了流固耦合作为SBLIs被动流动控制手段的概念。

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引用次数: 0