Journal of Fluids and Structures最新文献_第6页

Fluid-structure interaction analysis of an elastic surface-piercing propellers 弹性表面穿孔螺旋桨的流固耦合分析

IF 3.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2024-11-21 DOI: 10.1016/j.jfluidstructs.2024.104228

M Pakian Bushehri , MR Golbahar Haghighi , P Malekzadeh , E Bahmyari

In high-speed planing craft, surface-piercing propellers (SPPs) operate semi-submerged in a two-phase air-water environment, facing stress and displacement from variable forces. In this paper, the fluid-structure interaction (FSI) of the SPP is investigated at immersion ratios of 30 %, 50 %, 70 % and 90 %, under low and high advance coefficients. A coupling of Reynolds-averaged Navier–Stokes equations (RANS) and elasticity theory are used to simulate fluid dynamics and the blade deformation with the multi-physics computational fluid dynamics software STAR-CCM+. The analysis is performed after several rotations of the SPPs at five different positions. The results show that at the advance coefficient of 0.4, a higher immersion ratio increases torque, thrust, efficiency, maximum stress, and maximum displacement. When the advance coefficient is equal to one, the efficiency, maximum stress, and maximum displacement remain constant for the immersion ratio above 50 %. The maximum displacement occurs at the blade tip, while maximum stress is at the trailing edge root. Most blade deformations happen where the blade enters the water, aligns perpendicularly with the water surface, and exits. The two-phase flow around the blade increases its displacement.

在高速刨削艇中，表面推进器（SPP）半浸没在空气-水两相环境中运行，面临着来自可变力的应力和位移。本文研究了 SPP 在浸入比为 30%、50%、70% 和 90% 时，在低和高推进系数下的流固耦合（FSI）问题。使用多物理场计算流体动力学软件 STAR-CCM+，将雷诺平均纳维-斯托克斯方程（RANS）和弹性理论耦合，模拟流体动力学和叶片变形。在 SPP 于五个不同位置旋转数次后进行分析。结果表明，当推进系数为 0.4 时，较高的浸入比会增加扭矩、推力、效率、最大应力和最大位移。当超前系数等于 1 时，浸入比超过 50 % 时，效率、最大应力和最大位移保持不变。最大位移出现在叶尖，而最大应力则出现在后缘根部。大多数叶片变形发生在叶片进入水中、与水面垂直并离开水面的地方。叶片周围的两相流增加了叶片的位移。

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引用次数: 0

Unsteady load mitigation through passive pitch 通过被动俯仰减轻不稳定载荷

IF 3.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2024-11-21 DOI: 10.1016/j.jfluidstructs.2024.104216

Yabin Liu , Riccardo Broglia , Anna M. Young , Edward D. McCarthy , Ignazio Maria Viola

Mitigation of load fluctuations due to flow unsteadiness is critical in a broad range of applications, including wind/tidal turbines, and aerial/underwater vehicles. While the use of active control systems is an established practice in engineering, passive systems are not well understood, and the limits of their efficacy are yet to be ascertained. To this end, the present study aims to provide new insights into the effectiveness of passive pitching in the mitigation of lift fluctuations in the most demanding case of fast, high-amplitude variations of the free stream speed and direction. We perform fluid-structure interaction simulations of a two-dimensional free-to-pitch rigid foil. Our study reveals that the lift amplitude of the force fluctuations can be decreased by at least two-thirds through passive pitching. The efficacy of the unsteady load mitigation is only weakly dependent on the exact pitching axis location, and the optimal position is upstream and close to the axis of the foil. These results may inform the design of passive control systems of wind/tidal turbines and aerial/underwater vehicles and provide new insights into interpreting the control strategy of natural flyers such as insects and birds.

在包括风力/潮汐涡轮机和航空/水下航行器在内的多种应用中，减缓因流动不稳定性引起的负载波动至关重要。虽然使用主动控制系统是工程领域的惯例，但人们对被动系统的了解并不多，其功效的局限性也有待确定。为此，本研究旨在对被动俯仰系统在自由流速度和方向快速、高振幅变化的最苛刻情况下减缓升力波动的有效性提供新的见解。我们对二维自由俯仰刚性箔片进行了流固耦合模拟。我们的研究表明，通过被动俯仰，力波动的升力振幅至少可以降低三分之二。减轻非稳定载荷的效果只与俯仰轴的具体位置有微弱的关系，最佳位置在箔片轴线的上游和附近。这些结果可为风力/潮汐涡轮机和空中/水下飞行器被动控制系统的设计提供参考，并为解读昆虫和鸟类等自然飞行器的控制策略提供新的见解。

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引用次数: 0

Numerical investigation of fluid–structure interaction in a pilot-operated microfluidic valve 先导微流控阀门中流体与结构相互作用的数值研究

IF 3.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Journal of Fluids and Structures

Pub Date : 2024-11-21 DOI: 10.1016/j.jfluidstructs.2024.104226

Ahmed Aissa-Berraies , E. Harald van Brummelen , Ferdinando Auricchio

The present paper is concerned with numerical investigation of the performance of a pilot-operated control valve based on shape memory alloy actuation control. The valve under investigation can be integrated into miniaturized hydraulic systems and is developed to perform precise dispensing, mixing, or dosing tasks while being able to withstand relatively high pressure differences. The study evaluates the valve’s response under the current ON/OFF and the desired proportional control regimes using numerical methods for fluid–structure interaction. The computational model replicates the operation of the valve, which requires an understanding of the complex interactions between the fluid flow with the pressurized valve and the contact with the valve seat during the opening and closing processes. In addition, the model leverages advanced numerical techniques to overcome several complexities arising mainly from the geometrical, material, and contact nonlinearities, and to mitigate the shortcomings of the partitioned fluid–structure interaction approach. Several 3D fluid–structure-contact-interaction simulations are conducted to examine the valve’s structural and flow behavior under varying pressure conditions. Results indicate that the valve is adequate for ON/OFF actuation control but is susceptible to flow-induced vibrations during the proportional control regime that occurs due to the sharp pressure drop in the valve-seat gap and the ensuing Venturi effect, which counteract the opening of the main valve. The fluid–structure-interaction simulations provide insight into the mechanism underlying the flow-induced vibrations, which can serve to improve the design and enhance the performance of the valve in microfluidic applications.

本文对基于形状记忆合金执行控制的先导控制阀的性能进行了数值研究。所研究的阀门可集成到微型液压系统中，用于执行精确的分配、混合或配料任务，同时能够承受相对较高的压力差。这项研究采用流体与结构相互作用的数值方法，评估了阀门在当前开/关和所需比例控制状态下的响应。计算模型复制了阀门的运行过程，这就要求了解在打开和关闭过程中，流体流动与受压阀门以及与阀座接触之间复杂的相互作用。此外，该模型还利用先进的数值技术克服了主要由几何、材料和接触非线性引起的若干复杂问题，并减轻了分区流固耦合方法的缺点。我们进行了多次三维流体-结构-接触-相互作用模拟，以检查阀门在不同压力条件下的结构和流动行为。结果表明，该阀门适用于 ON/OFF 驱动控制，但在比例控制状态下，由于阀座间隙中的急剧压降和随之产生的文丘里效应（Venturi effect）会抵消主阀的开启，因此容易发生由流动引起的振动。流体-结构-相互作用模拟深入揭示了流动诱发振动的机理，有助于改进微流控应用中阀门的设计并提高其性能。

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引用次数: 0

Flow-induced buckling of a bistable beam in uniform flow 均流中双稳态梁的流动诱导屈曲

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.2024.104220

Leixin Ma , Wenyu Chen , Ruosi Zha , Alejandra Hernandez Escobar

Recent developments in soft materials enable the design and manufacturing of bistable flexible structures. Their fast snap-through buckling mechanisms have been utilized to introduce fast locomotion. In this paper, we aim to understand the impact of fluid–structure interaction (FSI) on the dynamics of bistable structures. We report the numerical analysis of the snap-through buckling phenomena for several bistable flexible structures fixed at both ends. The motion is driven by the fluid loading of different flow speeds. The large deformation of the bistable structure is coupled with the incoming fluid flow via the Arbitrary Lagrangian–Eulerian (ALE) method. During the snap-through buckling process, the corresponding structural deformation patterns, hydrodynamic force distributions, and fluid patterns are discussed. Larger steady-state deformation is found for the bistable structure, compared to its mono-stable counterpart in the same flow condition. The Cauchy number is found to be the critical parameter affecting the buckling dynamics and dimensionless strain energy stored in the system. A prediction model for the dimensionless strain energy as a function of the Cauchy number is proposed. The hydrodynamic lift force generated by the fluid is found to increase the total strain energy of these bistable structures. The research could provide insight in designing morphable marine energy devices and lightweight bioinspired propulsion systems.

软材料的最新发展使得双稳态柔性结构的设计和制造成为可能。双稳态柔性结构的快速屈曲机制已被用于引入快速运动。本文旨在了解流固耦合（FSI）对双稳态结构动力学的影响。我们报告了对几种两端固定的双稳态柔性结构的扣穿屈曲现象的数值分析。运动由不同流速的流体负载驱动。双稳态结构的大变形通过任意拉格朗日-欧拉（ALE）方法与流入的流体流耦合。讨论了在快穿屈曲过程中，相应的结构变形模式、流体动力分布和流体模式。发现在相同的流动条件下，双稳态结构的稳态变形比单稳态结构更大。研究发现，考奇数是影响屈曲动力学和系统中存储的无量纲应变能的关键参数。提出了一个无量纲应变能与考奇数函数关系的预测模型。研究发现，流体产生的流体动力升力会增加这些双稳态结构的总应变能。这项研究可为设计可变形海洋能源装置和轻质生物启发推进系统提供启示。

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引用次数: 0

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