Journal of Fluids and Structures最新文献

Modeling and simulation of shock wave-vehicle interaction in hyperloop tubes with shock attenuation via pseudo-perforated tube wall 基于伪穿孔管壁减振的超回路管内冲击波与车辆相互作用建模与仿真

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2026-02-05 DOI: 10.1016/j.jfluidstructs.2026.104502

Rajdeep Deb

Shock wave generated due to fast moving vehicle inside Hyperloop tube is studied, especially for its interaction with structures such as tube end wall and vehicle. The generation of corresponding reflection waves and its properties are estimated using analytical modeling based on the nozzle analogy and piston analogy. The interaction of reflection wave with vehicle and its corresponding impact on vehicle drag and flow properties around the vehicle is estimated using unsteady Reynolds-averaged Navier Stokes (URANS) equations. The parametric study of vehicle drag and reflection wave properties is obtained for varying blockage ratio (BR), vehicle speed (U_v), tube pressure (p_t), and vehicle geometry. The supersonic conditions developed in the vehicle tail are found to be modified due to interaction of vehicle with reflection wave, and multiple oblique shocks are observed behind the vehicle with increased blockage ratio and vehicle speed. In addition, secondary reflection wave propagating ahead of vehicle due to interaction with shock waves leads to pressure rise ahead of vehicle. As a consequence, an instantaneous rise in drag is observed. The mitigating measure to deal with the corresponding decrease in vehicle speed is estimated based on Proportional-Integral-Derivative (PID) control theory. The PID parameters are calculated, and the timescale for vehicle speed control is studied for varying control parameters. Special features on the tube wall of type pseudo-perforated wall are simulated to obtain reduced shock strength and shock speed for incident and reflecting waves. It is observed that such features of the tube wall allow for a substantial decrease in vehicle drag by modifying the shock properties.

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引用次数: 0

Symmetry breaking in three-degree-of-freedom flow-induced vibration of the circular cylinder with a splitter plate 带分流板圆柱三自由度流激振动的对称性破缺

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2026-01-23 DOI: 10.1016/j.jfluidstructs.2026.104519

Yue-Hao Sun , Yu-Ding Qi , Zhen Chen

This study numerically investigates the three-degree-of-freedom (3-DOF) flow-induced vibration of a circular cylinder with a splitter plate in the laminar flow. Key focus is placed on the competition between the lock-in response and the wake-induced symmetry breaking over a wide range of reduced velocities U* and splitter plate lengths L*. The results reveal that the 3-DOF lock-in response significantly delays the onset of symmetry breaking compared to the 1-DOF flow-induced rotation (FIR) case. This interaction gives rise to the mode competition between the lock-in and the symmetry breaking (CLS) for the first time, which can be further categorized into CLS-I where the lock-in suppresses the symmetry breaking and CLS-II where the two responses coexist. And the temporal evolution of these two competing modes is clearly illustrated using the continuous wavelet transform (CWT). Furthermore, the frequency analysis and the dynamic mode decomposition (DMD) demonstrate that each regime possesses a unique dynamic feature. The lock-in regime is characterized by the main frequency and its third harmonic, while the symmetry breaking state is dominated by the main frequency and the second harmonic. Finally, it is shown that the splitter plate length is a critical parameter that demarcates these regimes. These findings provide a comprehensive map of the structural response and offer new insights into the complex physics of mode competition in the 3-DOF flow induced vibration of the circular cylinder.

本文对带分流板的圆柱在层流中的三自由度流激振动进行了数值研究。重点放在锁定响应和尾迹引起的对称破缺之间的竞争，在很大范围内降低速度U*和分裂板长度L*。结果表明，与1-DOF流致旋转（FIR）情况相比，3-DOF锁定响应显著延迟了对称破缺的发生。这种相互作用首次引起了锁锁和对称破缺（CLS）之间的模式竞争，可进一步分为锁锁抑制对称破缺的CLS- i和两种响应共存的CLS- ii。利用连续小波变换（CWT）清晰地描述了这两种竞争模式的时间演化。此外，频率分析和动态模态分解（DMD）表明，每个区域都具有独特的动态特征。锁相态以主频率及其三次谐波为特征，而对称性破缺态以主频率和二次谐波为主。最后，研究表明，分频板长度是划分这些区域的关键参数。这些发现提供了结构响应的全面地图，并为圆柱三自由度流激振动中模式竞争的复杂物理提供了新的见解。

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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 : 2026-01-23 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

An improved WCNS-Z-based ghost-cell immersed boundary method and its application in shock-obstacle interaction simulations 基于改进wcns - z的鬼胞浸入边界法及其在冲击-障碍相互作用模拟中的应用

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2026-01-22 DOI: 10.1016/j.jfluidstructs.2026.104517

Huanhuan Yang , Lin Bi , Yanqun Jiang

Shock-obstacle interactions (such as shock diffraction, reflection, and vortex shedding) are typical phenomena in high-speed flows. Cartesian grids have become a research focus for studying such flow phenomena due to their automatic generation capability and strong adaptability to complex geometries. However, in shock-complex geometry interactions, the flow near walls undergoes intense variations, making high-fidelity boundary treatment a bottleneck in Cartesian grid numerical simulations. Traditional high-order interpolation tends to generate numerical oscillations in high-gradient regions near solid surfaces, while low-order methods lack sufficient accuracy in smooth flow regions. To address these issues, this paper develops an improved high-order ghost-cell immersed boundary method (GCIBM) based on least-squares high-order polynomial reconstruction. The proposed approach introduces a novel nonlinear weighting function and strictly enforces solid-wall boundary conditions, enabling adaptive blending between first-order (discontinuous regions) and third-order (smooth regions) extrapolation. Additionally, to overcome the accuracy degradation of the classical third-order WCNS-Z scheme at critical points, a modified WCNS-ZM scheme with a new smoothness indicator is proposed, significantly enhancing global accuracy and convergence efficiency. Combined with the high-order ghost-cell immersed boundary method, this approach effectively resolves the conflict between numerical stability and accuracy in shock-obstacle simulations. Numerical experiments on several benchmark cases demonstrate the superiority of the proposed method in capturing strong discontinuities and boundary treatment.

激波-障碍相互作用（如激波衍射、反射和涡流脱落）是高速流动中的典型现象。笛卡尔网格以其自动生成能力和对复杂几何形状的强适应性成为研究此类流动现象的研究热点。然而，在激波-复杂几何相互作用中，壁面附近的流动经历了强烈的变化，使得高保真边界处理成为笛卡尔网格数值模拟的瓶颈。传统的高阶插值方法在靠近固体表面的高梯度区域容易产生数值振荡，而低阶插值方法在光滑流动区域缺乏足够的精度。针对这些问题，本文提出了一种改进的基于最小二乘高阶多项式重构的高阶鬼胞浸入边界法。该方法引入了一种新的非线性加权函数，并严格执行实体壁边界条件，实现了一阶（不连续区域）和三阶（光滑区域）外推之间的自适应混合。此外，为了克服经典三阶WCNS-Z格式在临界点处精度下降的问题，提出了一种新的光滑指标改进的WCNS-ZM格式，显著提高了全局精度和收敛效率。该方法与高阶鬼胞浸入边界法相结合，有效地解决了冲击障碍仿真中数值稳定性与精度之间的矛盾。数值实验表明，该方法在强不连续面捕获和边界处理方面具有优越性。

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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 : 2026-01-22 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

Modeling and computational fluid dynamics validation of a nonholonomically constrained two-rigid-body swimming system 非完整约束双刚体游泳系统建模及计算流体动力学验证

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2026-01-19 DOI: 10.1016/j.jfluidstructs.2026.104510

J. Ardister, J. Geddes, B.F. Feeny, J. Yuan

A simple nonholonomic dynamics model is developed as a low-order model for generating undulatory swim-like motions, validated through computational fluid dynamics (CFD) simulations. The rigid-body-dynamics model generates swimming motion by imposing a nonholonomic (NH) constraint on the tail of a two-body system, requiring that tail-fin velocity aligns with the tail angle, while the head moves in a straight line through a slot constraint. The system has one degree of freedom, with equations of motion derived using Lagrange multipliers. Two-dimensional CFD simulations validate the model in an incompressible Newtonian fluid, where the resolved tail fin interacts with fluid through the immersed boundary method until steady-state swimming is achieved. The validation demonstrates excellent quantitative agreement between CFD and model predictions for body orientation angle and normal fluid force across variations in fin motion amplitude, period, and Reynolds number. While an exact NH constraint point does not exist, an effective period-averaged NH location can be identified for successful model predictions. At higher Reynolds numbers, the two-body kinematics displays independence from the Reynolds number variation. The CFD data reveal that the two-body model captures the type of power-law relationship between Reynolds and Strouhal numbers governing undulatory swimming from tadpoles to whales, indicating that the simplified two-link model is representative of swimming dynamics in continuous geometries at various scales. A key limitation is that the drag force model requires a priori CFD calibration to match steady-swim velocity, limiting standalone predictive capability. The results demonstrate that the low-order NH constraint-based model effectively captures essential swimming dynamics, offering a robust alternative to existing fluid-force models.

建立了一个简单的非完整动力学模型，作为产生波动游泳运动的低阶模型，并通过计算流体动力学（CFD）模拟进行了验证。刚体动力学模型通过对两体系统的尾部施加非完整（NH）约束来产生游泳运动，要求尾鳍速度与尾部角度一致，而头部通过狭缝约束进行直线运动。该系统具有一个自由度，其运动方程由拉格朗日乘子导出。二维CFD模拟验证了该模型在不可压缩牛顿流体中的有效性，在不可压缩牛顿流体中，分解后的尾翼通过浸入边界法与流体相互作用，直至实现稳态游动。验证表明，CFD和模型预测的体取向角和法向流体力在鳍运动振幅、周期和雷诺数变化中的定量一致性非常好。虽然不存在精确的NH约束点，但可以确定有效的周期平均NH位置，以获得成功的模型预测。在较高的雷诺数下，两体运动学不受雷诺数变化的影响。CFD数据表明，两体模型捕获了从蝌蚪到鲸鱼的波动游泳的Reynolds数和Strouhal数之间的幂律关系，表明简化的两链模型代表了不同尺度下连续几何的游泳动力学。一个关键的限制是阻力模型需要先验的CFD校准来匹配稳定游动速度，限制了独立的预测能力。结果表明，基于低阶NH约束的模型有效地捕获了基本的游泳动力学，为现有的流体力模型提供了一种鲁棒的替代方案。

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引用次数: 0

A numerical investigation on the interaction of a thunderstorm downburst and an atmospheric boundary layer wind 雷暴下暴与大气边界层风相互作用的数值研究

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2026-01-19 DOI: 10.1016/j.jfluidstructs.2026.104515

J. Žužul , A. Ricci , M. Burlando

Downburst winds rarely occur as an isolated phenomenon. Instead, they are more likely to occur in the presence of background Atmospheric Boundary Layer (ABL) winds. However, only a limited number of studies have investigated this interaction. This study provides new insights into the interaction between ABL flow and downburst winds by analyzing velocity profiles, peak values, and spatiotemporal characteristics using Computational Fluid Dynamics (CFD) simulations. ABL and downburst winds previously reproduced in the WindEEE Dome facility are here numerically simulated with three approaches: URANS, SAS and LES. The interaction at the colliding front generates a stagnation region that slows down the Primary Vortex (PV) propagation, while significant levels of ABL entrainment into the downburst are observed. The PV at the along ABL direction is found to cause the strongest radial outflows. At these locations, a short-lived counter-rotating Secondary Vortex (SV) also develops. Although structural models are not included in the simulations, the study emphasizes the importance of accurately resolving the wind field that affects the wind loading on structures during such events. In addition to the limited amount of high-resolution full-scale data available, the present analysis contributes to advancing the knowledge of the complex dynamics of ABL-downburst interaction. The flow fields presented here are valuable as loading input conditions in structural analyses, and particularly useful for assessing fluid-structure interaction response of slender infrastructure like transmission line towers and telecommunication towers.

下突风很少作为孤立现象发生。相反，它们更有可能发生在背景大气边界层（ABL）风的存在下。然而，只有有限数量的研究调查了这种相互作用。本研究利用计算流体动力学（CFD）模拟分析了ABL流与下爆风的速度分布、峰值和时空特征，为ABL流与下爆风之间的相互作用提供了新的见解。以前在WindEEE Dome设施中重现的ABL和下突风在这里用三种方法进行了数值模拟：URANS， SAS和LES。碰撞锋面的相互作用产生了一个滞止区，减缓了主涡旋（PV）的传播，同时观察到大量的ABL被卷入下爆。沿ABL方向的PV引起最强的径向外流。在这些位置，一个短暂的反向旋转二次涡（SV）也会发展。虽然模拟中没有包括结构模型，但研究强调了准确解析在此类事件中影响结构风荷载的风场的重要性。除了有限的高分辨率全尺寸可用数据外，本文的分析有助于提高对abl -下击相互作用复杂动力学的认识。本文所提出的流场在结构分析中作为荷载输入条件是有价值的，对于评估像输电线路塔和电信塔这样的细长基础设施的流固耦合响应特别有用。

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引用次数: 0

Experimental study of along-/across-wind aeroelastic response coupling in a tall square tower 方形高塔顺/横风气动弹性耦合试验研究

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2026-01-17 DOI: 10.1016/j.jfluidstructs.2026.104516

Wenshan Shan , Qingshan Yang , Yong Chul Kim , Chao Li , Chen Li , Shuai Huang

Tall slender structures, including high-rise buildings and towers, exhibit significant sensitivity to wind-induced vibrations owing to their flexibility and minimal intrinsic damping. While extensive studies have focused on across-wind aeroelastic effects, recent findings suggest that coupling between along-wind and across-wind responses could happen under certain conditions. However, this phenomenon remains insufficiently explored. This study examines the coupling of wind-induced responses in two structural principal orientations of a tall square tower with an aspect ratio of 16, utilizing aeroelastic model tests performed in a large-scale boundary layer wind tunnel. The influence of the wind direction, structural damping ratio, and wind velocity on coupled responses is systematically examined. The observations demonstrate that at wind direction θ = 0°, the across-wind response exhibits significant aeroelastic behavior, with a strong correlation but negligible coupling with the along-wind response. Moreover, at oblique wind directions, pronounced coupling effects of displacements in X and Y orientations emerge, particularly around the vortex shedding frequency, as confirmed by coherence function analysis. These findings provide valuable perspectives into the aeroelastic behavior of slender structures subjected to varying wind conditions and highlight the necessity of considering multi-directional coupling effects in wind-resistant design.

高大细长的结构，包括高层建筑和塔楼，由于其灵活性和最小的固有阻尼，对风致振动表现出显著的敏感性。虽然广泛的研究集中在横风气动弹性效应上，但最近的研究结果表明，在某些条件下，顺风和横风响应之间的耦合可能会发生。然而，这一现象仍未得到充分探讨。本研究利用在大型边界层风洞中进行的气动弹性模型试验，研究了宽高比为16的方形高塔在两个结构主方向上的风致响应耦合。系统地研究了风向、结构阻尼比和风速对耦合响应的影响。结果表明，在风向θ = 0°时，横风响应表现出显著的气动弹性特性，与顺风响应具有较强的相关性，但耦合可以忽略。此外，相干函数分析证实，在斜风向下，X和Y方向上的位移出现了明显的耦合效应，特别是在旋涡脱落频率附近。这些发现为研究细长结构在不同风条件下的气动弹性行为提供了有价值的视角，并强调了在抗风设计中考虑多向耦合效应的必要性。

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引用次数: 0

Hydrodynamic behaviour of two asymmetrically submerged piezoelectric plates 两个非对称浸没压电片的水动力特性

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2026-01-16 DOI: 10.1016/j.jfluidstructs.2026.104509

Toushik Roy , Sourav Gupta , Soumen De , R. Gayen

In the quest for sustainable and renewable energy sources, use of piezoelectric wave energy converters for harnessing ocean wave energy is becoming increasingly important. However, mathematical modeling of the related problems is somewhat difficult. Thus, in this study we have endeavoured to solve the problem of wave interaction with two unequal vertically submerged piezoelectric plates present in water of uniform finite depth. The piezoelectric nature of the plates gives rise to boundary conditions involving fourth order derivatives with complex coefficients. We have developed a semi-analytical method where this boundary condition is tackled by employing Green’s function technique and the boundary value problem is transformed into a coupled system of integral equations employing a mixed Fourier transform. The integral equations are solved using a Galerkin method to find the reflection and transmission coefficients and the power absorption efficiency of the piezoelectric system. The influence of structural parameters, such as length asymmetry, depth of submergence, spacing and boundary conditions on the scattering coefficients and the efficiency of the plates is systematically examined. Results demonstrate that geometric asymmetry between the plates can significantly enhance energy conversion performance. The findings provide valuable insights for the efficient design and deployment of submerged piezoelectric wave energy converters in real-world marine environments.

在寻求可持续和可再生能源的过程中，使用压电波能转换器来利用海浪能量变得越来越重要。然而，相关问题的数学建模有些困难。因此，在本研究中，我们试图解决在均匀有限深度的水中存在的两个不相等的垂直淹没压电片的波相互作用问题。板的压电性质产生了涉及复系数四阶导数的边界条件。我们开发了一种半解析方法，利用格林函数技术解决了这个边界条件，并利用混合傅里叶变换将边值问题转化为积分方程的耦合系统。利用伽辽金法求解积分方程，求出了压电系统的反射系数、透射系数和功率吸收效率。系统地研究了长度不对称、淹没深度、间距和边界条件等结构参数对散射系数和效率的影响。结果表明，板间的几何不对称可以显著提高能量转换性能。研究结果为水下压电波能转换器在实际海洋环境中的有效设计和部署提供了有价值的见解。

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引用次数: 0

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 : 2026-01-15 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