Journal of Fluids and Structures最新文献_第4页

An analytical model for early-stage mooring design in floating wind turbines 浮式风力发电机组早期系泊设计分析模型

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2025-12-05 DOI: 10.1016/j.jfluidstructs.2025.104475

Pierpaolo Loprieno , Fabio Rizzo , Elisa Leone , Dora Foti , Giuseppe Roberto Tomasicchio , Agostino Lauria

The design of mooring systems for Floating Offshore Wind Turbines presents significant engineering challenges, particularly in managing structural dynamics and fluid-structure interactions. While analytical models are less developed in this sector compared to experimental and numerical approaches, they offer key advantages in streamlining early-stage design by reducing time, costs, and errors. This study proposes a novel Linearized Single Degree of Freedom analytical model to efficiently predict the dynamic response of spar-type Floating Offshore Wind Turbines under hydrodynamic loads. While Morison-based and linear mooring formulations are well established, in this work a closed-form solution is derived to accurately estimate translational displacements and mooring tensions. Implemented in MATLAB R2022a, the proposed model was validated against wave-tank experiments and subsequently compared with OpenFOAM and OpenFAST simulations to evaluate its accuracy levels. Despite its reduced formulation, the model accurately captures stiffness, damping, and hydrodynamic forces. Frequency- and time-domain analysis show strong agreement with experimental data, confirming its reliability in predicting platform displacements and mooring line tensions. It has also been demonstrated that the analytical model is able to yield precise results regarding both maximum and minimum values of these parameters, while effectively capturing their relationships. The model, with significantly lower computational demands than numerical simulations and comparable accuracy, serves as a valuable tool for early-stage design and optimization. While the proposed model is restricted to spar-type floating platforms under regular wave conditions, future work will aim to incorporate aerodynamic loads, irregular waves, and alternative platform configurations, without compromising computational efficiency.

浮式海上风力涡轮机系泊系统的设计面临着重大的工程挑战，特别是在结构动力学和流固耦合管理方面。虽然与实验和数值方法相比，分析模型在这一领域的发展较少，但它们通过减少时间、成本和错误，在简化早期设计方面提供了关键优势。本文提出了一种新颖的线性化单自由度分析模型，以有效地预测浮式海上风力机在水动力载荷作用下的动力响应。虽然基于莫里森和线性系泊公式已经很好地建立起来，但在这项工作中，推导了一个封闭形式的解决方案，以准确地估计平移位移和系泊张力。在MATLAB R2022a中实现，通过波浪槽实验验证了所提出的模型，随后与OpenFOAM和OpenFAST仿真进行了比较，以评估其精度水平。尽管其简化的公式，该模型准确地捕捉刚度，阻尼和水动力。频域和时域分析结果与实验数据吻合较好，证实了该方法预测平台位移和系泊索张力的可靠性。还证明了分析模型能够产生关于这些参数的最大值和最小值的精确结果，同时有效地捕获它们的关系。该模型的计算量明显低于数值模拟，且精度相当，是早期设计和优化的宝贵工具。虽然所提出的模型仅限于规则波浪条件下的桅杆式浮动平台，但未来的工作将旨在纳入气动载荷、不规则波浪和替代平台配置，同时不影响计算效率。

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引用次数: 0

Mechanics of flow-induced pitching of an inverted foil undergoing cross-flow 横流作用下倒立翼的流致俯仰力学

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2025-12-03 DOI: 10.1016/j.jfluidstructs.2025.104476

Kai Qi, Md. Mahbub Alam

This study investigates the fundamental mechanics of flow-induced pitching of an inverted foil undergoing cross-flow for reduced velocity U_r = 25 − 47 and damping ratio ζ = 0 − 0.325. The Reynolds number (Re), based on the foil chord length, is fixed at Re = 900. The foil oscillation amplitude, pitching frequency, hydrodynamic stiffness, hydrodynamic damping, and energy harvesting efficiency are presented and analyzed. The inverted foil system exhibits three distinct response modes: stationary, deflected pitching, and symmetric pitching. Symmetric pitching, occurring for a range of U_r centered around U_r = 37, involves a large amplitude oscillation about the equilibrium position of the foil. The hydrodynamic stiffness plays a crucial role in determining the three response modes and the pitching frequency. While hydrodynamic damping is negative during the forward stroke and positive during the return stroke, the hydrodynamic stiffness remains negative during both strokes, making the pitching frequency consistently lower than the natural frequency. The timing between forward and return strokes varies with U_r and ζ. The forward stroke is shorter than the return stroke for small ζ values while the pattern reverses for larger ζ values. Equal timing between the two strokes occurs at intermediate ζ values. The symmetric pitching in both space and time domains makes the efficiency as high as 16 % at U_r = 37 and ζ = 0.130. A deep understanding of the underlying mechanism of flow-induced vibration provides guidance for improving the energy efficiency of fully passive flapping-foil generators.

本文研究了在降低速度Ur = 25 - 47和阻尼比ζ = 0 - 0.325的情况下，倒立箔在横流过程中流致俯仰的基本机理。根据箔弦长，雷诺数Re固定为Re = 900。给出并分析了翼片振荡幅值、俯仰频率、动水刚度、动水阻尼和能量收集效率。倒立箔系统表现出三种不同的响应模式：静止、偏转俯仰和对称俯仰。对称俯仰发生在以Ur = 37为中心的Ur范围内，涉及到围绕箔的平衡位置的大幅度振荡。水动力刚度对三种响应模式和俯仰频率的决定起着至关重要的作用。虽然前冲程的水动力阻尼为负，回程的水动力阻尼为正，但两个冲程的水动力刚度都为负，使得俯仰频率始终低于固有频率。向前和返回笔划之间的时间随Ur和ζ而变化。对于小的ζ值，向前行程比返回行程短，而对于较大的ζ值，模式相反。在中间的ζ值处，两个动作之间的时间相等。对称俯仰在空间和时间域使得效率高达16%，在Ur = 37和ζ = 0.130。深入了解流激振动的潜在机理，为提高全被动扑翼发电机的能量效率提供了指导。

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引用次数: 0

Numerical study on load and deformation characteristics of vehicle during high-speed water entry 车辆高速入水载荷与变形特性数值研究

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2025-12-03 DOI: 10.1016/j.jfluidstructs.2025.104473

Yao Shi , Zhenpeng Liu , Hairui Zhao , Guang Pan , Denghui Qin

In this study, a numerical model for high-speed water entry of vehicle was established based on the structured arbitrary Lagrangian-Eulerian (S-ALE) method. The model showed good predictive accuracy when compared with experimental results. Using this validated model, numerical simulations were conducted for varying entry velocities (100∼300 m/s) and angles (60° and 90°). Time-domain characteristics including acceleration, pressure, and stress during water entry are systematically obtained, with frequency-domain characteristics further revealed through power spectral analysis. Additionally, the load and deformation characteristics of vehicle’s head are thoroughly investigated. Correlation coefficient calculations indicated that the pressure and stress curves exhibited a consistent trend with the deflection curve, revealing a significant coupling relationship between structural deformation and load characteristics during high-speed water entry.

本文基于结构化任意拉格朗日-欧拉（S-ALE）方法，建立了车辆高速入水的数值模型。通过与实验结果的比较，表明该模型具有较好的预测精度。利用该验证模型，对不同的进入速度（100 ~ 300 m/s）和角度（60°和90°）进行了数值模拟。系统地获得了入水过程中的加速度、压力和应力等时域特征，并通过功率谱分析进一步揭示了频域特征。此外，还深入研究了车辆头部的载荷和变形特性。相关系数计算表明，压力和应力曲线与挠度曲线呈现一致的趋势，表明高速入水过程中结构变形与荷载特性之间存在显著的耦合关系。

引用次数: 0

Vibration suppression characteristics of piezoelectric metamaterial pipe conveying fluid based on shunt circuits 基于并联电路的压电超材料管道输送流体的振动抑制特性

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2025-11-26 DOI: 10.1016/j.jfluidstructs.2025.104474

Qifa Lu , Hongwei Song , Renzhuo Du , Wensheng Ma , Chunchuan Liu

This paper proposes a novel metamaterial pipe with controllable bandgap characteristics, which is constructed by attaching shunted piezoelectric patches to a fluid-conveying pipe along the axial direction. The vibration transmission coefficient and wave attenuation constant of the metamaterial pipe are calculated using an analytical model that combines Euler-Bernoulli beam theory and Timoshenko beam theory. The main contribution of this work lies in the combined analytical model can calculate the vibration and wave propagation characteristics of circular metamaterial pipe with sectorial annular piezoelectric patches. The calculation accuracy is quantitatively verified through the results in published literature and finite element numerical simulations. Research results indicate that Bragg scattering (BS) bandgap and electromechanical local resonance (LR) bandgap can be generated and used for low-frequency vibration reduction. Due to the damping effect of internal fluid flow, the weak non-reciprocal propagation of bending waves occurs for the metamaterial pipe with non-zero fluid velocity. The transmission coefficient can be tuned by flow velocity, and controllable bandgap characteristics can be achieved by designing shunt circuit parameters. In addition, the bandgap coupling characteristics of metamaterial pipes are studied and the hybrid bandgap is obtained, which can be used to achieve broadband low-frequency vibration reduction of engineering fluid-conveying pipes.

本文提出了一种具有可控带隙特性的新型超材料管道，该管道是在流体输送管道上沿轴向附加分流式压电片构成的。采用欧拉-伯努利梁理论和Timoshenko梁理论相结合的解析模型计算了超材料管道的振动传递系数和波衰减常数。本文工作的主要贡献在于所建立的组合解析模型能够计算具有扇形环形压电片的圆形超材料管的振动和波传播特性。通过已发表的文献和有限元数值模拟的结果，定量地验证了计算的准确性。研究结果表明，可以产生Bragg散射（BS）带隙和机电局部共振（LR）带隙，并将其用于低频减振。由于内部流体流动的阻尼作用，在非零流体速度的超材料管道中，弯曲波发生弱的非倒数传播。传输系数可通过流速调节，带隙特性可通过设计分流电路参数实现可控。此外，研究了超材料管道的带隙耦合特性，得到了混合带隙，可用于实现工程输液管道的宽带低频减振。

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引用次数: 0

Unsteady aerodynamic mechanisms of wing flexibility in dragonfly flapping flight 蜻蜓扑翼飞行中翅膀柔韧性的非定常气动机理

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2025-11-24 DOI: 10.1016/j.jfluidstructs.2025.104471

Mengzong Zheng , Yuanjun Deng , Jinze Liang , Guanting Su , Tianyu Pan , Liansong Peng , Zhiping Li , Qiushi Li

This study investigates the effect of flexible wings on the aerodynamic performance of dragonfly flapping flight through both experimental and numerical simulations. The model experiment employed an isotropic flexible wing, and the results showed that the flexible deformation of the dragonfly wing led to a 12% increase in average lift. On the numerical side, an anisotropic flexible wing model replicating the mechanical properties of the dragonfly wing is constructed, and fluid–structure interaction (FSI) simulations are conducted. The simulation results show that the cycle-averaged lift coefficient of the flexible wing increases by 7.86% compared to its rigid counterpart. Comparative analysis of the flow field reveals three key unsteady aerodynamic mechanisms associated with wing flexibility: the chordwise camber mechanism, which stabilizes the attachment of the leading-edge vortex (LEV) to the upper surface of the wing, generating stable lift; the accelerated rotation mechanism, which increases the amplitude and speed of wing rotation and facilitates vortex accumulation; and the spanwise bending mechanism, which increases the flapping angle range and enhances lift.

本文通过实验和数值模拟研究了柔性机翼对蜻蜓扑动飞行气动性能的影响。模型实验采用了各向同性柔性机翼，结果表明，蜻蜓机翼的柔性变形使平均升力提高了12%。在数值方面，建立了模拟蜻蜓翅膀力学特性的各向异性柔性翼模型，并进行了流固耦合（FSI）仿真。仿真结果表明，柔性机翼的循环平均升力系数比刚性机翼提高了7.86%。流场对比分析揭示了与机翼柔性相关的三个关键非定常气动机制：弦向弯曲机制，稳定前缘涡在机翼上表面的附着，产生稳定升力；加速旋转机制，增加了机翼旋转的幅度和速度，有利于旋涡积累；并采用展向弯曲机构，增加了扑翼角度范围，提高了升力。

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引用次数: 0

Analytical study of water wave diffraction and radiation by a submerged sphere in front of a partially reflective vertical wall 部分反射垂直壁面前浸没球对水波衍射和辐射的分析研究

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2025-11-24 DOI: 10.1016/j.jfluidstructs.2025.104472

Aijun Li , Siming Zheng , Yong Liu

The problem of water wave diffraction and radiation by a submerged sphere in front of a partially reflective wall is solved by using the partial mirror image method. Additional velocity potentials of reduced diffracted/radiated waves from the mirror image of the sphere with respect to the vertical wall are introduced to satisfy the partially reflective condition on the vertical wall. The velocity potentials of diffracted/radiated waves from the sphere and its mirror image are expressed using the multipole expansion method in local spherical coordinate systems with the origins located at the centers of the two spheres. Subsequently, by applying the transformation technology of local spherical coordinate systems for multipoles, the unknown coefficients in the velocity potentials are determined through the boundary condition on the real sphere surface. The wave exciting forces on the submerged sphere and the added mass and radiation damping due to the sphere’s oscillation are calculated. The correctness of the analytical solution is validated by considering the solution convergence and the comparison with published results in the literature. Based on the analytical solution, the effects of the reflection coefficient of the wall, the frequency, the sphere-wall spacing, and the submergence depth on the hydrodynamic quantities are examined. Results indicate that the magnitude of the reflection coefficient imposes obvious effects on the amplitudes of the hydrodynamic quantities, whereas variations in the phase of the reflection coefficient shift the frequencies at which hydrodynamic quantities exhibit maxima and minima. Increasing the sphere-wall spacing causes the hydrodynamic quantities to oscillate more rapidly with frequency.

采用部分镜像法，解决了部分反射壁前淹没球对水波的衍射和辐射问题。为了满足垂直壁上的部分反射条件，引入了球面镜像相对于垂直壁上的简化衍射/辐射波的附加速度势。用多极展开法在局域球坐标系中以两个球的中心为原点表示球体及其镜像的衍射/辐射波的速度势。随后，应用局部球坐标系多极变换技术，通过实际球面上的边界条件确定速度势中的未知系数。计算了水下球的波浪激励力和由于球的振荡而增加的质量和辐射阻尼。通过考虑解的收敛性和与已发表的文献结果的比较，验证了解析解的正确性。基于解析解，考察了壁反射系数、频率、球壁间距和淹没深度对水动力量的影响。结果表明，反射系数的大小对水动力量的幅值有明显的影响，而反射系数相位的变化使水动力量出现最大值和最小值的频率发生偏移。增大球壁间距会使水动力量随频率的振荡更快。

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引用次数: 0

CyberDiver: An untethered robotic impactor for water-entry experiments 电子潜水器：用于入水实验的无系绳机器人撞击器

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2025-11-22 DOI: 10.1016/j.jfluidstructs.2025.104461

John T. Antolik , Eli A. Silver , Jesse L. Belden , Daniel M. Harris

We present the CyberDiver, an untethered robotic impactor capable of actively modulating the fluid physics during high-speed water entry. First, we utilize the CyberDiver to extend our understanding of the water entry of passively flexible systems, designing a high-bandwidth controller that enables the CyberDiver to operate as a cyber–physical system that permits an arbitrary programmable structural coupling to be experimentally tested. Onboard sensors record the body acceleration during impact and reveal that the introduction of damping or a nonlinear force-versus-displacement structural law can significantly reduce impact loading as compared to a linear elastic case, with implications for damage mitigation in aerospace and naval applications. Next, by operating the CyberDiver in a displacement control mode, we demonstrate that the splash size can be dramatically altered depending on the parameters of an active maneuver, laying a groundwork for better understanding the techniques of human competitive divers.

我们介绍了CyberDiver，这是一种无系绳机器人撞击器，能够在高速入水过程中主动调节流体物理。首先，我们利用CyberDiver扩展了我们对被动柔性系统入水的理解，设计了一个高带宽控制器，使CyberDiver能够作为一个网络物理系统运行，允许对任意可编程结构耦合进行实验测试。机载传感器记录了碰撞过程中的车身加速度，结果表明，与线性弹性情况相比，引入阻尼或非线性力与位移结构规律可以显著降低冲击载荷，这对航空航天和海军应用中的损伤缓解具有重要意义。接下来，通过在位移控制模式下操作CyberDiver，我们证明飞溅大小可以根据主动机动的参数显着改变，为更好地理解人类竞技潜水员的技术奠定基础。

引用次数: 0

Comparative study on a downstream cylinder versus splitter plate-based proximity interference on FIV of a circular cylinder 下游圆柱体与分流板接近干扰对圆柱体FIV影响的比较研究

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2025-11-20 DOI: 10.1016/j.jfluidstructs.2025.104469

Abhishek Abhishek, Subhasisa Rath, Sandip K. Saha, Atul Sharma

The study presents the effect of bluffness on flow-induced vibration of an elastically-mounted cylinder subjected to proximity-interference from a downstream stationary cylinder (bluff body) and a rigid splitter-plate (streamlined). Numerical simulations are performed for non-dimensional gap G* = 0.1,0.3, 0.5 and reduced velocities U* = 3 – 20, at a constant Reynolds number Re = 100. The upstream cylinder exhibits in-phase (ϕ = 0°) proximity-induced galloping (PIG), except for an in-phase to anti-phase (ϕ = 180°) jump at G* = 0.5 of the plate case, and the onset of proximity-induced staggered vibration (PISV) at U* = 20, G* = 0.1 of the cylinder case. With decreasing G*, the A* and maximum gap flow rate

Q_{g, m a x}^{*}

increases for the plate case while decreases for the cylinder, indicating a strong link between

Q_{g, m a x}^{*}

and vibrational amplitude. Three primary lift mechanisms are identified during PIG oscillation: anti-phase restoring vortex-induced lift, in-phase decelerating lift, and in-phase galloping lift. The persistence of the gap-side vortex and associated vortex-induced lift in the plate case, even at the smallest gap (G* = 0.05)—contrasted with its suppression for the cylinder case, emerges as the fundamental difference between bluff and streamlined body interference. The well-known asymptotic amplitude variation (with U*) of PIG is caused by the enhanced gap-side vortex, establishing the anti-phase restoring vortex as the key mechanism governing self-limiting amplitude characteristics in both PIG and VIV. Further, at G* = 0.1, the vibrational regime map is presented in terms of downstream structure bluffness B and U*.

研究了当下游静止圆柱（钝体）和刚性隔板（流线型）相邻干涉时，钝度对弹性安装圆柱流激振动的影响。在恒定雷诺数Re = 100条件下，对无量纲间隙G* = 0.1、0.3、0.5和减速速度U* = 3 ~ 20进行了数值模拟。上游圆柱体表现出同相（φ = 0°）近似诱导的策动（PIG），除了在G* = 0.5的平板情况下的同相到反相（φ = 180°）跳跃，以及在U* = 20, G* = 0.1的圆柱体情况下近似诱导的交错振动（PISV）的开始。随着G*的减小，平板壳体的A*和最大间隙流量Qg、max*增大，圆柱壳体的最大间隙流量Qg、max*减小，说明Qg、max*与振动幅值之间存在较强的联系。在PIG振荡过程中，确定了三种主要的升力机制：反相位恢复涡致升力、同相位减速升力和同相位加速升力。即使在最小的间隙中（G* = 0.05），平板情况下间隙侧涡和相关的涡诱导升力的持续存在（与圆柱体情况下的抑制相比）是钝面和流线型体干涉的根本区别。众所周知，PIG的渐近振幅变化（带U*）是由间隙侧涡增强引起的，这表明反相位恢复涡是控制PIG和VIV自限振幅特性的关键机制。进一步，在G* = 0.1时，以下游结构钝度B和U*表示振动状态图。

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引用次数: 0

Structural control of floating offshore wind turbines via active yaw control 基于主动偏航控制的浮式海上风力发电机结构控制

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2025-11-17 DOI: 10.1016/j.jfluidstructs.2025.104462

Yize Wang, Zhenqing Liu

Active yaw control can be utilized to maximize the total power output of a wind farm. This study proposes a novel active yaw control optimization algorithm that can simultaneously increase the farm power output and reduce the turbine structural dynamics. To achieve this goal, the effects of the environmental conditions and yaw angles on the structural dynamics of floating offshore wind turbines are investigated first. Then, accurate surrogate models are trained via the radial basis function neural network to predict the structural dynamics of the wind turbine. The maximum error of the surrogate models is only 6.22%. Finally, the attained surrogate models are utilized by a differential evolution algorithm to optimize the yaw angles of the wind turbines. The numerical results indicate that active yaw control, which aims to maximize the total power output and minimize the tower bottom moment in the pitch direction, is preferable for minimizing tower top displacement and floating platform displacement. After yaw control optimization, the total power output of the wind farm increases by 3.1%, and the tower bottom moment of the wind turbine decreases by 12.6%.

主动偏航控制可以用来最大限度地提高风力发电场的总输出功率。本研究提出了一种新的主动偏航控制优化算法，该算法可以在增加机场输出功率的同时减小涡轮结构动力学。为了实现这一目标，首先研究了环境条件和偏航角对浮式海上风力机结构动力学的影响。然后，通过径向基函数神经网络训练准确的代理模型来预测风力机的结构动力学。代理模型的最大误差仅为6.22%。最后，利用差分进化算法对风力机的横摆角进行优化。数值结果表明，主动偏航控制以最大输出总功率和最小俯仰方向塔底力矩为目标，比最小化塔顶位移和浮动平台位移更有效。偏航控制优化后，风电场总输出功率提高3.1%，风机塔底力矩降低12.6%。

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引用次数: 0

Mitigation of broadband duct flow noise using liner with gradient surface resonant compliance 利用具有梯度表面共振顺应性的衬垫降低宽带管道流动噪声

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2025-11-17 DOI: 10.1016/j.jfluidstructs.2025.104452

Ali Abdullah , Randolph C.K. Leung , Racer K.H. Lam , Muhammad Rehan Naseer , Irsalan Arif

Broadband noise mitigation in flow ducts remains a crucial area of study, especially in the low-frequency regime where conventional liner technologies such as dissipative liners, micro-perforated panels, and Helmholtz resonators are often ineffective. To address this limitation, the use of interior duct surface resonant compliance, which leverages aeroacoustic-structural interactions to mitigate low-frequency noise in duct flow, is found to be particularly promising. We investigate a novel approach using multiple compliant liner units, each comprising elastic panels backed by air-filled cavities, strategically flush-mounted on the duct walls. By strategically tuning the fluid-loaded resonant frequency of each elastic panel to introduce gradient surface resonant compliance, we create overlapping stopbands that enhance low-frequency noise mitigation. In this study, a robust numerical methodology based on the perturbation evolution method is utilized. A weak broadband acoustic excitation is introduced to simulate a realistic aeroacoustic flow duct environment. A detailed parametric study is carried out to compare three compliant liner system configurations: (1) baseline with uniform surface resonance distribution, (2) increasing resonance distribution, and (3) decreasing resonance distribution along the flow direction. The study confirms that the baseline compliant configuration yields remarkable reductions in broadband noise. The gradient-resonance compliant configurations further improve the performance, achieving enhanced low-frequency noise mitigation and increased overall sound transmission loss. The findings of the study demonstrate that strategically varying the fluid-loaded resonant frequencies of elastic panels enhances the structural resonant characteristics, thereby increasing the stopband width by 18.0 % for increasing resonance distribution configuration, while a 7.0 % widened stopband was demonstrated by decreasing resonance distribution with maximum transmission of 50.0 dB. Furthermore, the compliant liner systems demonstrated a remarkably lower drag penalty (≤ 10 %) than the minimum value observed in conventional acoustic liner experiments reported in the literature.

流动管道中的宽带降噪仍然是一个重要的研究领域，特别是在低频区域，传统的衬垫技术，如耗散衬垫、微穿孔板和亥姆霍兹谐振器往往无效。为了解决这一限制，利用内部管道表面共振顺应性，利用气动声学-结构相互作用来减轻管道流动中的低频噪声，被认为是特别有前途的。我们研究了一种使用多个柔性衬垫单元的新方法，每个衬垫单元由弹性面板组成，背面是充气腔，战略性地安装在管道壁上。通过战略性地调整每个弹性面板的流体负载谐振频率，引入梯度表面谐振顺应性，我们创建了重叠的阻带，增强了低频噪声的缓解。本文采用了一种基于微扰演化法的鲁棒数值方法。引入微弱的宽带声激励，模拟了一个真实的气动声流道环境。通过详细的参数化研究，对比了三种柔性衬垫系统配置：(1)表面共振分布均匀的基线、(2)沿流动方向共振分布增加的基线和(3)沿流动方向共振分布减少的基线。该研究证实，基线符合配置产生显著减少宽带噪声。符合梯度共振的配置进一步提高了性能，实现了低频噪声的增强缓解，并增加了整体声音传输损失。研究结果表明，有策略地改变弹性板的流体加载谐振频率可以增强结构的谐振特性，从而使阻带宽度增加18.0%，从而增加了共振分布构型；而通过减小共振分布，最大传输率为50.0 dB，则表明阻带宽度增加了7.0%。此外，与文献中报道的传统声学衬垫实验中观察到的最小值相比，柔性衬垫系统的阻力损失显著降低（≤10%）。

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引用次数: 0