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

Numerical analysis of glaze ice accretion on cables by considering the effects of typical in-plane vibrations 通过考虑典型面内振动的影响对电缆上的釉冰沉积进行数值分析

IF 3.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2024-11-20 DOI: 10.1016/j.jfluidstructs.2024.104229

Chao Zhou , Jiaqi Yin

During the glaze icing process, cables experience vibrations due to the presence of aerodynamic forces, gravity, and other external forces. In most existing glaze icing models, the cables are assumed to be fixed, and water film is just run-down streams that do not reflect the complexity of the ice accretion process. To reveal the effects of in-plane motions of cable on the glaze icing process, two typical in-plane motions of aeolian vibration and galloping are taken into consideration and a mathematical water film-ice layer model is proposed for the first time. Based on the water film-ice layer model, ice accretion and water flow on the vibrating cables are studied, and key parameters of Collision Efficiency (CE), aerodynamic coefficients, and water film are evaluated by comparison with fixed cables. Moreover, by iterating the discretized mass and energy conservation equations with the computed aerodynamic coefficients, the effects of in-plane motions of the cable on water film and ice shapes are computed. The model then is verified with published experimental and numerical data. The results show that in-plane motions of the cables enlarge the windward face in dynamic forms which have certain effects on water film and ice shapes, and the model could provide accurate predictions of ice accretion.

在釉面结冰过程中，由于空气动力、重力和其他外力的存在，电缆会发生振动。在现有的大多数釉面结冰模型中，电缆被假定为固定的，水膜也只是流下的水流，不能反映复杂的结冰过程。为揭示缆索平面内运动对釉面结冰过程的影响，考虑了风化振动和奔腾两种典型的平面内运动，首次提出了水膜-冰层数学模型。基于水膜-冰层模型，研究了振动缆索上的积冰和水流，并通过与固定缆索的对比，评估了碰撞效率（CE）、空气动力系数和水膜等关键参数。此外，通过利用计算出的空气动力系数迭代离散质量和能量守恒方程，计算了缆索平面内运动对水膜和冰形状的影响。然后用已公布的实验和数值数据对模型进行了验证。结果表明，缆索的平面内运动以动态形式扩大了迎风面，对水膜和冰的形状产生了一定的影响，该模型可以准确预测冰的增加。

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引用次数: 0

Stress relaxation and thermo-visco-elastic effects in fluid-filled slits and fluid-loaded plates 充满流体的狭缝和流体负载板中的应力松弛和热粘弹效应

IF 3.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2024-11-16 DOI: 10.1016/j.jfluidstructs.2024.104219

Erik García Neefjes , David Nigro , Raphaël C. Assier , William J. Parnell

In this paper, we theoretically analyse wave propagation in two canonical problems of interest: fluid-filled thermo-visco-elastic slits and fluid-loaded thermo-visco-elastic plates. We show that these two configurations can be studied via the same pair of dispersion equations with the aid of the framework developed in García Neefjes et al. (2022), which incorporates thermal effects. These two problems are further interrelated, since in the short wavelength limit (relative to the slit/plate width) the respective modes are governed by the same dispersion equation, commonly known as the Scholte–Stoneley equation. It is the Scholte-type modes that are mainly analysed in this paper. We illustrate results when the fluid is water, although the theory is valid for any Newtonian fluid. Both ‘hard’ and ‘soft’ solids are compared, with the emphasis being placed on the importance of thermo-viscoelastic effects, particularly when stress relaxation is considered. Two main recent works are discussed extensively, namely (Cotterill et al., 2018) for slits and (Staples et al., 2021) for loaded plates, both of which do not incorporate viscoelastic mechanisms. We show how the consideration of viscoelasticity can extend the results discussed therein, and explain the circumstances under which they arise.

在本文中，我们从理论上分析了波在两个典型问题中的传播：充满流体的热粘弹性狭缝和充满流体的热粘弹性板。我们表明，借助加西亚-尼夫杰斯等人（2022 年）所开发的包含热效应的框架，可以通过同一对频散方程来研究这两种配置。这两个问题还相互关联，因为在短波长极限（相对于狭缝/平板宽度），各自的模式受同一频散方程（通常称为 Scholte-Stoneley 方程）控制。本文主要分析肖尔特模式。虽然该理论适用于任何牛顿流体，但我们还是以水为流体为例进行说明。本文对 "硬 "和 "软 "固体进行了比较，重点强调了热粘弹效应的重要性，尤其是在考虑应力松弛时。我们广泛讨论了最近的两项主要研究，即针对狭缝的研究（Cotterill 等人，2018 年）和针对加载板的研究（Staples 等人，2021 年），这两项研究都没有纳入粘弹性机制。我们展示了考虑粘弹性如何扩展其中讨论的结果，并解释了产生这些结果的情况。

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引用次数: 0

Numerical Prediction of Two-Dimensional Coupled Galloping and Vortex-Induced Vibration of Square Cylinders Under Symmetric/Asymmetric Flow Orientations 对称/不对称流向下方形圆柱体二维耦合湍流和涡流诱导振动的数值预测

IF 3.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2024-11-14 DOI: 10.1016/j.jfluidstructs.2024.104215

Yan Naung Aye, Narakorn Srinil

This study presents an advanced numerical model for predicting a two-dimensional coupled galloping and vortex-induced vibration (VIV) in cross-flow and in-line directions of square cylinders under symmetric and asymmetric flow orientations. The present model combines the quasi-steady theory for the galloping with the nonlinear structure-wake oscillators simulating VIV, capturing the time-varying drag and lift hydrodynamic forces with the time-averaged and fluctuating components. By placing a flexibly mounted square cylinder in uniform flow at an initial angle of incidence, the cylinder is subject to instantaneous changes in the dynamic angle of attack accounting for relative flow-structure velocities. Modelling of such features in cross-flow and in-line directions for low and high mass ratio systems extends previous studies which have mostly focused on cross-flow responses of square cylinders with high mass ratios at a zero angle of incidence. New sets of empirical coefficients governing the drag and lift fluid forces for both the quasi-steady and wake oscillator approaches are introduced by calibrating with available experimental data in the literature, applicable to predict several flow-induced vibration phenomena under arbitrary flow-structure orientations. Mathematical criteria for the onset of two- and one-dimensional galloping instability are presented, verifying the likelihood of galloping occurrence. Parametric investigations are carried out to highlight the important effects of flow incidence angle, mass-damping ratio (Scruton number) and in-line response on the prediction of galloping and VIV in comparison with experimental results. By varying the reduced velocity parameter, the present model captures key qualitative features of the dominant galloping, interfering galloping-VIV and dominant VIV through the response amplitudes, mean drift displacements, oscillation frequencies, fluid force components and motion trajectories. Contributions from in-line responses are found to be meaningful for the interfering galloping-VIV system with a low mass-damping ratio and for an asymmetric flow orientation. The present model could be further calibrated and applied to other fluid-structure interaction applications with non-circular cross-sectional geometries under omnidirectional flow directions.

本研究提出了一种先进的数值模型，用于预测对称和非对称流向下方形圆柱体在横流和直流方向上的二维耦合奔腾和涡流诱导振动（VIV）。本模型结合了奔腾的准稳态理论和模拟 VIV 的非线性结构-振动振荡器，利用时均和波动分量捕捉时变的阻力和升力流体动力。通过在均匀流中以初始入射角放置一个灵活安装的方形圆柱体，圆柱体的动态攻角会发生瞬时变化，并考虑到相对流体-结构速度。对低质量比和高质量比系统的横流和直流方向上的这种特征进行建模，扩展了以前的研究，以前的研究主要集中在零入射角下高质量比方形气缸的横流响应。通过与文献中现有的实验数据进行校准，为准稳态方法和唤醒振荡器方法引入了新的控制阻力和升力流体力的经验系数集，适用于预测任意流动结构方向下的几种流动诱导振动现象。提出了二维和一维奔腾不稳定性发生的数学标准，验证了奔腾发生的可能性。与实验结果相比，参数研究突出了流动入射角、质量阻尼比（斯克鲁顿数）和在线响应对奔腾和 VIV 预测的重要影响。通过改变减速度参数，本模型通过响应振幅、平均漂移位移、振荡频率、流体力分量和运动轨迹，捕捉到了主导奔腾、干扰奔腾-VIV 和主导 VIV 的主要定性特征。对于低质量阻尼比和非对称流向的干扰奔腾-VIV 系统来说，在线响应的贡献是有意义的。本模型可进一步校准并应用于全向流动方向下具有非圆形横截面几何结构的其他流固耦合应用。

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引用次数: 0

A three-dimensional nonlinear hydroelastic model for rectangular floating elastic plates and the examination on the peak frequency with maximum nonlinear response 矩形浮动弹性板的三维非线性水弹性模型以及对最大非线性响应峰值频率的研究

IF 3.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2024-11-13 DOI: 10.1016/j.jfluidstructs.2024.104217

S. Liang, Y. Gou, B. Teng

The nonlinear interaction between nonlinear waves and a three-dimensional floating elastic plate is simulated by a time-domain nonlinear potential flow model. On the free surface, the 4th-order Runge-Kutta scheme with a semi-Lagrangian approach is adopted in the time-stepping process. The classical thin-plate theory is selected to simulate the motion of the elastic plate. The higher-order boundary element method (HOBEM) is employed to solve the corresponding boundary value problem at each time step. After validation of the present model, a particular frequency phenomenon is successfully observed in a three-dimensional hydroelastic problem, which shows that the second harmonic displacements at the centre point of the upwave side and downwave side of the elastic plate near a particular frequency are significantly large. In addition, the effect of the plate width on the particular frequency phenomenon is discussed.

通过时域非线性势流模型模拟了非线性波与三维浮动弹性板之间的非线性相互作用。在自由表面上，采用半拉格朗日的四阶 Runge-Kutta 方案进行时间步进。选择经典的薄板理论来模拟弹性板的运动。采用高阶边界元法（HOBEM）求解每个时间步的相应边界值问题。在对本模型进行验证后，成功地在三维水弹性问题中观测到了特定频率现象，表明在特定频率附近，弹性板上波侧和下波侧中心点的二次谐波位移明显较大。此外，还讨论了板宽对特定频率现象的影响。

引用次数: 0

Numerical study of consecutive water entries in flowing water with twin spheres side-by-side 流水中并排孪生球体连续进水的数值研究

IF 3.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2024-11-12 DOI: 10.1016/j.jfluidstructs.2024.104218

Xu Wang , Jiazhen Zhao , Xianzhong Tan , Chao Qi , Aochen Zhao , He Li , Ruisheng Sun , Xujian Lyu

A three-dimensional numerical model with six-degree-of-freedom is developed to simulate the side-by-side entry of twin spheres into flowing water. With the explicit volume of fluid (VOF) approach, the shear-stress transport (SST) k-ω model is adopted to delineate the turbulence structures within the flow, while the independent movements of the two spheres are tracked using advanced multi-overset mesh technology. The numerical findings elucidate the effects of water flow on cavity dynamics, flow field evolution, forces, and trajectories during consecutive sphere entries. Distinct flow field characteristics emerge depending on whether the trailing sphere enters the upstream side or downstream side. The flow-induced tilting of the first cavity results in a different scale of expansion of the trailing cavity with respect to that in quiescent water, diminishing the attractive force on the upstream-side sphere and enhancing it for the downstream-side sphere. As the lateral distance between the spheres increases, the forces of attraction and repulsion generated by the leading cavity become marginal in their effect on the trailing sphere's trajectory, particularly when compared with the impact force of the water flow.

建立了一个具有六自由度的三维数值模型来模拟双球并排进入流水的情况。通过显式流体体积（VOF）方法，采用剪应力传输（SST）k-ω 模型来划分流体中的湍流结构，同时利用先进的多网格技术跟踪两个球体的独立运动。数值研究结果阐明了连续进入球体时水流对空腔动力学、流场演变、力和轨迹的影响。根据尾部球体是进入上游侧还是下游侧，会出现不同的流场特征。由水流引起的第一个空腔的倾斜导致尾部空腔的扩张尺度与静水中的扩张尺度不同，从而减弱了上游侧球体的吸引力，增强了下游侧球体的吸引力。随着球体之间横向距离的增加，前腔产生的吸引力和排斥力对尾部球体轨迹的影响变得微不足道，尤其是与水流的冲击力相比。

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引用次数: 0

A new approach for spatio-temporal interface treatment in fluid–solid interaction using artificial neural networks employing coupled partitioned fluid–solid solvers 利用人工神经网络和流固耦合分区求解器处理流固相互作用时空界面的新方法

IF 3.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2024-11-02 DOI: 10.1016/j.jfluidstructs.2024.104200

Farrukh Mazhar, Ali Javed

Partitioned fluid–solid interaction (FSI) problems involving non-conforming grids pose formidable challenge in interface treatment, especially for information exchange, interface tracking, and field variable interpolation between solvers in both space and time. These demand special considerations for accurate and efficient simulations. This paper presents an application of artificial neural networks (ANN) for the interface treatment in a coupled FSI problem employing partitioned solvers. A shallow time-series ANN (nonlinear auto-regressive model with exogenous inputs, NARX) scheme is proposed to handle the exchange of Neumann/Dirichlet information at the coupling interface. This scheme involves two interface treatment models that were developed and analysed. The proposed models interpolate and transfer loads from the fluid to the solid domains, and conversely, displacements from the solid to the fluid domains between non-collocated grids. To validate this approach, we tested it on a 3D FSI problem, which involved damped oscillations of a flexible flap submerged in a fluid cavity. Adequately trained NARX interface models demonstrate reliable input–output mapping and accurate prediction of transient behaviour at the interface. Additionally, we explored the concept of reduced-order modelling (ROM) in the time domain. This allowed us to reduce the model’s complexity by half. Different training algorithms were evaluated to enhance the efficiency and performance of the proposed scheme. The study demonstrates that NARX networks trained with Bayesian Regularization (BR) and Levenberg–Marquardt (LM) algorithms exhibit the best accuracy, while the scaled conjugate gradient (SCG)-based training method provides better computational efficiency with acceptable accuracy. Overall, the NARX interface models provide precise performance and offer a viable potential for applications in FSI problems requiring accurate and faster computations.

涉及不规则网格的分区流固耦合（FSI）问题给界面处理带来了巨大挑战，特别是在空间和时间上的信息交换、界面跟踪和求解器之间的场变量插值。这些都需要特别考虑，以实现准确高效的模拟。本文介绍了人工神经网络（ANN）在采用分区求解器的耦合 FSI 问题界面处理中的应用。本文提出了一种浅层时间序列 ANN（具有外生输入的非线性自回归模型，NARX）方案，用于处理耦合界面上的 Neumann/Dirichlet 信息交换。该方案涉及两个已开发和分析的界面处理模型。所提议的模型插值并将载荷从流体域转移到固体域，反之，将位移从固体域转移到非同轴网格间的流体域。为了验证这种方法，我们在三维 FSI 问题上进行了测试，该问题涉及浸没在流体腔中的柔性襟翼的阻尼振动。经过充分训练的 NARX 接口模型展示了可靠的输入输出映射，并准确预测了接口处的瞬态行为。此外，我们还在时域中探索了降阶建模（ROM）的概念。这使我们能够将模型的复杂性降低一半。我们对不同的训练算法进行了评估，以提高拟议方案的效率和性能。研究表明，使用贝叶斯正则化（BR）和莱文伯格-马尔卡特（LM）算法训练的 NARX 网络表现出最佳的准确性，而基于缩放共轭梯度（SCG）的训练方法则提供了更好的计算效率和可接受的准确性。总之，NARX 接口模型具有精确的性能，为需要精确和快速计算的 FSI 问题提供了可行的应用潜力。

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引用次数: 0

Condensation solution method for fluid-structure interaction dynamic models of structural system 结构系统流固耦合动力学模型的凝结解法

IF 3.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2024-11-01 DOI: 10.1016/j.jfluidstructs.2024.104214

Yu Hu , Zhiguang Song , Erasmo Carrera

In the fluid-structure dynamic analysis, the low solution efficiency seriously restricts the passive and active vibration control of structures. But so far, this issue has not been well addressed. Component mode synthesis (CMS) is an efficient method for dynamic analysis of structures. However, since the concept of mode for the fluid is very weak, the CMS is not suitable for solving fluid-structure interaction dynamic problems. Another type of dimension reduction method is dynamic condensation originating from Guyan method. In this paper, introducing the idea of CMS and combining the Guyan method, an efficient condensation solution method is proposed to solve the fluid-structure interaction dynamic models. In the dynamical modeling, both the structure field and fluid field are discretized using 20-node three dimensional elements. The elemental fluid-structure interaction equations of motion are formulated using the Hamilton principle and weighted residual method. The solid and fluid fields are divided into substructures, and all the degrees of freedom (DOFs) of the two fields are divided into interior structure DOFs, boundary structure DOFs, interior master fluid DOFs, interior salve fluid DOFs, as well as boundary fluid DOFs. In the solid substructures, higher orders of mode are neglected to realize a large-scale dimensional reduction, while for the fluid field, the slave DOFs are replaced by the master DOFs. To conduct the verification of the present method, experiment is carried out. The comparison results show the high accuracy and efficiency of the condensation solution method.

在流体-结构动力学分析中，低求解效率严重制约了结构的被动和主动振动控制。但迄今为止，这一问题尚未得到很好的解决。构件模态合成（CMS）是一种高效的结构动态分析方法。然而，由于流体的模态概念非常薄弱，CMS 并不适用于解决流固耦合动力学问题。另一种降维方法是源于 Guyan 方法的动态凝聚法。本文引入 CMS 的思想，结合 Guyan 方法，提出了一种高效的凝缩求解方法来求解流固耦合动力学模型。在动力学模型中，结构场和流体场均采用 20 节点三维元素离散化。利用汉密尔顿原理和加权残差法制定了元素流固相互作用运动方程。将固体场和流体场划分为子结构，并将两个场的所有自由度（DOFs）划分为内部结构 DOFs、边界结构 DOFs、内部主流体 DOFs、内部主流体 DOFs 以及边界流体 DOFs。在固体子结构中，忽略了高阶模，以实现大规模降维；而在流体场中，用主 DOF 代替从 DOF。为了对本方法进行验证，我们进行了实验。对比结果表明，冷凝求解法具有较高的精度和效率。

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引用次数: 0

Turbulence-induced vibration in annular flow of a rigid cylinder mounted on a cantilever beam 安装在悬臂梁上的刚性圆柱体环流中的湍流诱导振动

IF 3.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2024-11-01 DOI: 10.1016/j.jfluidstructs.2024.104213

Romain Lagrange , Loucas Plado Costante , Maud Kocher

This study investigates the fluid–structure interaction of two coaxial cylinders separated by a Newtonian fluid under turbulent axial flow. The theoretical framework treats the inner cylinder as a rigid body mounted on a flexible blade modeled as a Rayleigh beam. The goals of this study are to determine the free vibration modes and frequencies, identify the fluid-elastic instability threshold, and establish an analytical expression for the mean-square displacement of the structure. The approach integrates various fluid forces and torques, such as Archimedean thrust, fluid-elastic forces for a quiescent fluid, fluid-elastic forces due to flow, and the effects of fluid turbulence. The new approach reveals that vibration modes, frequencies, instability thresholds, and mean-square displacement each depend on a different set of dimensionless parameters: 8, 11, and 12, respectively. These parameters include the cylinder aspect ratio and fluid gap radius ratio. By incorporating models from the literature for viscous friction coefficients, turbulent pressure power spectral density, and coherence function, the study demonstrates stability conditions and the scaling of mean-square displacement with Reynolds number squared. The study, presented in a fully dimensionless formulation, aims to assist engineers in constructing small-scale experiments representative of pressure vessel vibrations. To facilitate this, a Python code for system stability determination and mean-square displacement calculation is provided.

本研究探讨了被牛顿流体隔开的两个同轴圆柱体在湍流轴向流下的流固相互作用。理论框架将内圆柱体视为安装在以瑞利梁为模型的柔性叶片上的刚体。本研究的目标是确定自由振动模式和频率，识别流体弹性不稳定性阈值，并建立结构均方位移的分析表达式。该方法综合了各种流体力和力矩，如阿基米德推力、静止流体的流体弹性力、流动引起的流体弹性力以及流体湍流的影响。新方法揭示了振动模式、频率、不稳定性阈值和均方位移分别取决于一组不同的无量纲参数：8、11 和 12。这些参数包括圆柱体长宽比和流体间隙半径比。通过结合文献中的粘性摩擦系数、湍流压力功率谱密度和相干函数模型，该研究展示了稳定性条件以及均方位移与雷诺数平方的比例关系。该研究以完全无量纲的形式呈现，旨在帮助工程师构建代表压力容器振动的小规模实验。为此，还提供了用于系统稳定性确定和均方位移计算的 Python 代码。

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引用次数: 0

Recurrent graph convolutional multi-mesh autoencoder for unsteady transonic aerodynamics 用于非稳态跨声速空气动力学的递归图卷积多网格自动编码器

IF 3.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2024-10-28 DOI: 10.1016/j.jfluidstructs.2024.104202

David Massegur , Andrea Da Ronch

Unsteady, high-fidelity aerodynamic load predictions around a three-dimensional configuration will remain computationally expensive for the foreseeable future. Data-driven algorithms based on deep-learning are an attractive option for reduced order modelling of complex, nonlinear systems. However, a dedicated approach is needed for applicability to large and unstructured domains that are typical in engineering. This work presents a geometric-deep-learning multi-mesh autoencoder framework to predict the spatial and temporal evolution of aerodynamic loads for a finite-span wing undergoing different types of motion. The novel framework leverages on: (a) graph neural networks for aerodynamic surface grids embedded with a multi-resolution algorithm for dimensionality reduction; and (b) a recurrent scheme for time-marching the aerodynamic loads. The test case is for the BSCW wing in transonic flow undergoing a combination of forced-motions in pitch and plunge. A comprehensive comparison between a quasi-steady and a recurrent approach is provided. The model training requires four unsteady, high-fidelity aerodynamic analyses which require each about two days of HPC computing time. For any common engineering task that involves more than four cases, a clear benefit in computing costs is achieved using the proposed framework as an alternative predictive tool: new cases are computed in seconds on a standard GPU.

在可预见的未来，围绕三维构型的非稳态、高保真空气动力载荷预测的计算成本仍将非常昂贵。基于深度学习的数据驱动算法对于复杂非线性系统的低阶建模来说是一种极具吸引力的选择。然而，要想适用于工程领域中典型的大型非结构化领域，还需要一种专门的方法。本研究提出了一种几何-深度学习多网格自动编码器框架，用于预测经历不同运动类型的有限跨度机翼的空气动力载荷的空间和时间演变。该新型框架利用了(a) 图神经网络用于气动表面网格，嵌入多分辨率算法以降低维度；(b) 循环方案用于气动载荷的时间进程。测试案例是在跨音速气流中的 BSCW 机翼，其俯仰和俯冲运动均为强制运动。对准稳定方法和循环方法进行了综合比较。模型训练需要进行四次非稳态高保真气动分析，每次分析需要大约两天的 HPC 计算时间。对于任何涉及四个以上案例的普通工程任务，使用所提出的框架作为替代预测工具，在计算成本方面可获得明显优势：在标准 GPU 上计算新案例只需几秒钟。

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引用次数: 0

On the characteristics of fluid flow field and oscillatory response of tuned liquid multi-column dampers 论调谐液体多柱阻尼器的流场特性和振荡响应

IF 3.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2024-10-28 DOI: 10.1016/j.jfluidstructs.2024.104206

Hao Ding , Jian Song , Xiaojun Fang

The tuned liquid column damper (TLCD) operates as a fluid counterpart to a tuned mass damper (TMD), harnessing the dynamics of liquid flow to effectively counteract unwanted vibrations, thereby achieving the stability within the structural system. Most recently, to overcome the shortcoming that conventional TLCDs can only control the vibration of structures in a single direction, a toroidal tuned liquid multi-column damper (TLMCD) was proposed and its control effectiveness was preliminarily validated. However, the hydrodynamic characteristics of the TLMCD remain elusive and warrant further clarification. Therefore, this study employs computational fluid dynamics (CFD) methodology to meticulously simulate the intricate three-dimensional multiphase flow dynamics within toroidal TLMCDs across a spectrum of excitation conditions, aiming to elucidate their hydrodynamic behaviors. The efficacy of the CFD-based simulation approach is validated through a comparative analysis of numerically computed and experimentally measured liquid displacement responses. The error magnitude of the simplified theoretical model for toroidal TLMCDs is assessed by comparing the outcomes derived from CFD simulations with the theoretical predictions. Furthermore, by visualizing the spatial and temporal distribution of fluid flow field, the three-dimensional fluid flow properties of toroidal TLMCDs are characterized. The findings presented highlight the frequency-dependent nonlinear characteristics of liquid column oscillatory responses, providing a valuable benchmark for the development of more refined theoretical models and guiding the optimization of fluid-type dampers.

调谐液柱阻尼器（TLCD）是一种与调谐质量阻尼器（TMD）相对应的流体阻尼器，利用液体流动的动力学特性有效抵消不必要的振动，从而实现结构系统的稳定性。最近，为了克服传统 TLCD 只能控制结构单向振动的缺点，有人提出了环形调谐液体多柱阻尼器（TLMCD），并初步验证了其控制效果。然而，TLMCD 的流体动力学特性仍然难以捉摸，需要进一步阐明。因此，本研究采用计算流体动力学（CFD）方法，细致模拟了环形 TLMCD 在各种激励条件下复杂的三维多相流动力学，旨在阐明其流体动力学行为。通过对数值计算和实验测量的液体位移响应进行对比分析，验证了基于 CFD 模拟方法的有效性。通过比较 CFD 模拟结果和理论预测结果，评估了环形 TLMCD 简化理论模型的误差幅度。此外，通过对流体流场的空间和时间分布进行可视化，还对环形 TLMCD 的三维流体流动特性进行了描述。研究结果突出了液柱振荡响应的频率非线性特征，为开发更精细的理论模型和指导流体型阻尼器的优化提供了宝贵的基准。

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引用次数: 0