Journal of Sound and Vibration最新文献_第10页

Design of six-parameter isolator using internal mass effect for improving vibration isolation 利用内质量效应设计提高隔振性能的六参数隔振器

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-22 DOI: 10.1016/j.jsv.2024.118859

Jing Li , Weipeng Li , Weidong Yu , Qingqing Xu , Hai Huang

Isolators designed based on a three-parameter model (or its equivalent five-parameter model) are used for vibration isolation of sensitive payloads. The three-parameter model consists of a spring arranged in parallel with an elastically supported damper. The three-parameter isolator performs better than conventional isolators, which are primarily based on a parallel spring–damper structure. However, it tends to sacrifice the resonance suppression at low frequencies when enhancing damping at high frequencies. Previous studies have shown that the internal moving mass of a three-parameter isolator, which had been neglected, can be beneficial for improving high-frequency vibration isolation; however, few design methods have been presented. Hence, we propose a six-parameter model based on the five-parameter model by considering the internal mass. This model combines the advantages of the internal mass effect and offers more designable parameters than the three-parameter model. In this study, the optimum damping of a six-parameter model was determined. An optimization method for the six-parameter model was proposed to maximize high-frequency isolation. Subsequently, an optimal six-parameter isolator was designed and tested. The results showed that the optimal six-parameter isolator can provide greater isolation by 30 dB than the three-parameter isolator at frequencies above 200 Hz, thereby validating the design method. This study provides new ideas for utilizing internal mass to improve vibration isolation.

基于三参数模型（或其等效的五参数模型）设计的隔振器用于敏感有效载荷的隔振。该三参数模型由一个与弹性支承阻尼器平行布置的弹簧组成。三参数隔振器的性能优于传统的基于并联弹簧-阻尼器结构的隔振器。然而，在提高高频阻尼的同时，往往会牺牲低频的谐振抑制。以往的研究表明，三参数隔振器的内部运动质量对提高高频隔振性能是有益的，而这一特性一直被忽略；然而，很少有设计方法被提出。因此，我们在考虑内部质量的五参数模型的基础上，提出了一个六参数模型。该模型结合了内部质量效应的优点，并提供了比三参数模型更多的可设计参数。在本研究中，确定了六参数模型的最佳阻尼。提出了一种六参数模型优化方法，使高频隔离最大化。随后，设计并测试了最优六参数隔离器。结果表明，在频率高于200 Hz的情况下，最优的六参数隔离器比三参数隔离器的隔离度提高了30 dB，从而验证了设计方法的有效性。该研究为利用内部质量提高隔振性能提供了新的思路。

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引用次数: 0

Dynamic characterization of permanent magnet electrodynamic suspension system with a novel passive damping magnet scheme 采用新型被动阻尼磁体方案的永磁电动悬架系统动态特性研究

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-22 DOI: 10.1016/j.jsv.2024.118849

Chuan Wu , Guanchun Li , Dong Wang , Jie Xu

In the paper, a 3D electromagnetic force analytical model incorporating the vertical vibration velocity of the permanent magnet is derived using the virtual magnetic charge method, which is used to examine the system’s dynamic properties. Then, a novel passive damping scheme based on permanent magnets is developed to enhance the system stability without increasing the complexity of the system. Finally, the dynamic experiment is carried out on the rotating platform employing a dynamic test apparatus, where the validity of the analytical model is checked and the effect of the damping magnet is explored. The results exhibit that the permanent magnet electrodynamic suspension system is self-stabilizing yet underdamped, and the vertical damping coefficient decreases as the velocity and airgap increase. The system has favorable stability in the absence of disturbance with a fluctuation of roughly 0.5 mm. The proposed damping scheme reduces the vibration overshoot from 41.18% to 32.47% and shortens the settling time from 3.29 s to 0.97 s. Meanwhile, the system is especially sensitive to long-wave irregularities in the high-speed range throughout the experiment with the track irregularity, where the vibration amplitude of the guidance system can be reduced by approximately 8 times from 4.6 mm to 0.57 mm by applying the damping magnet scheme. As a result, the proposed passive damping magnet scheme offers a pretty damping effect, which is capable of significantly improving the stability of the permanent magnet electrodynamic suspension system.

本文利用虚磁荷法建立了考虑永磁体垂直振动速度的三维电磁力分析模型，并对系统的动态特性进行了分析。在此基础上，提出了一种基于永磁体的无源阻尼方案，在不增加系统复杂性的前提下提高了系统的稳定性。最后，利用动态测试装置在旋转平台上进行了动态实验，验证了分析模型的有效性，并探讨了阻尼磁体的影响。结果表明：永磁电动悬架系统具有自稳定和欠阻尼特性，垂向阻尼系数随速度和气隙的增大而减小；该系统在无扰动的情况下具有良好的稳定性，波动约为0.5 mm。该阻尼方案将振动超调量从41.18%降低到32.47%，沉降时间从3.29 s缩短到0.97 s。同时，在整个实验过程中，系统对高速范围内的长波不平顺性特别敏感，采用阻尼磁体方案可将制导系统的振动幅值从4.6 mm降至0.57 mm，降低约8倍。结果表明，所提出的被动阻尼磁体方案具有良好的阻尼效果，能够显著提高永磁电动悬架系统的稳定性。

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引用次数: 0

A spectral element-based reduced order model for thermoacoustic stability analysis in waveguides 基于谱元的波导热声稳定性分析降阶模型

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-20 DOI: 10.1016/j.jsv.2024.118834

Dario Passato , Danilo Beli , Ines Lopez Arteaga

A novel approach to perform linear stability analysis using a spectral element-based reduced order model is proposed, thereby facilitating the comprehensive study of (thermo)acoustic (in)stability across complex waveguide configurations. Providing a generalization of a wave-based method (e.g. spectral element method) to the Laplace domain, this study is offering not only a new methodology for analyzing thermoacoustic systems but also expanding the application of the spectral element method and other wave-based techniques to a broader class of problems. By solving the wave equation in the Laplace domain, spectral elementary matrices can be defined in the complex plane in both wavenumber and frequency domains, allowing for an examination of system stability. This technique supports a wide range of waveguide investigations, whether using an analytical description to get the spectral matrix or a numerical method to determine the dispersion curves and eigenvectors in the cross-section. Additionally, the proposed method simplifies the implementation of parametric optimization procedures due to its low computational cost, thus offering significant advancements in the study of waveguide behavior of thermoacoustic systems.

提出了一种使用基于谱元的降阶模型进行线性稳定性分析的新方法，从而促进了跨复杂波导结构（热）声（in）稳定性的全面研究。本研究将基于波的方法（如谱元方法）推广到拉普拉斯域，不仅为热声系统分析提供了一种新的方法，而且将谱元方法和其他基于波的技术的应用扩展到更广泛的问题类别。通过在拉普拉斯域中求解波动方程，可以在波数域和频域的复平面上定义谱初等矩阵，从而允许对系统稳定性进行检查。该技术支持广泛的波导研究，无论是使用解析描述来获得光谱矩阵，还是使用数值方法来确定截面中的色散曲线和特征向量。此外，由于计算成本低，该方法简化了参数优化过程的实现，从而在热声系统波导行为的研究中取得了重大进展。

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引用次数: 0

Analytical solutions for free vibrations of rectangular cuboid elastic lattices and their continuous approximations

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-19 DOI: 10.1016/j.jsv.2024.118836

H.P. Nguyen , Noël Challamel , C.M. Wang

This paper presents analytical solutions for the free vibration of an elastic cuboid lattice (rectangular parallelepiped) with sliding supports along its planar boundaries. The lattice model includes both central and angular interactions. The free vibration problem is solved by formulating a 3D difference eigenvalue problem, and exact solutions for the eigenfrequencies and eigenmodes are derived analytically using a trigonometric discrete displacement field. A cubic equation for the eigenfrequency squares is obtained, with solutions determined using Cardano's formula. The derived exact solutions for the finite cuboid lattice are validated by comparison with solutions obtained from a discrete algebraic method, calibrated for accurate stiffness and mass properties both within the lattice and at its boundaries. Furthermore, these exact solutions for the 3D lattice are benchmarked against analytical solutions for the corresponding 3D continuum, based on classical elasticity, lattice-based gradient elasticity, and lattice-based nonlocal elasticity theories, demonstrating their accuracy and reliability for free vibration analysis.

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引用次数: 0

Modelling the effective sound propagation properties of a hexagonal acoustic metamaterial using a dissipative equivalent-fluid approach under different termination conditions 利用耗散等效流体方法模拟不同终止条件下六边形声超材料的有效声传播特性

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-19 DOI: 10.1016/j.jsv.2024.118855

Denilson Ramos , Francesco Pompoli , Cristina Marescotti , Luís Godinho , Paulo Amado-Mendes , Paulo Mareze

This paper presents a theoretical approach to assess the effective sound propagation properties of an acoustic system comprising multiple subwavelength resonators under grazing incidence. Consequently, the high capacity required to handle sound transmission, absorption and reflection are theoretically and experimentally reported. Viscothermal effects are considered by employing the dissipative equivalent-fluid approach and the respective analytical estimations of transport parameters provide accuracy in describing the resistive and reactive phenomena in the acoustic field for different termination conditions. The dissipative equivalent-fluid approach proposed here is contrasted with other well-established methods and numerical computing. The results evidence good agreement even when multiple resonances are associated, enabling the implementation of single, dual and triple resonance systems. The results of this work present a validated simplified approach that provides analytical derivations of the effective sound propagation properties in a complex association of side-branches Helmholtz resonators.

本文提出了一种理论方法，用于评估由多个亚波长谐振器组成的声学系统在掠入射条件下的有效声传播特性。因此，理论和实验报告了处理声音传播、吸收和反射所需的高容量。采用耗散等效流体方法考虑了粘热效应，并对传输参数进行了相应的分析估算，从而准确地描述了不同终止条件下声场中的阻力和反应现象。本文提出的耗散等效流体方法与其他成熟的方法和数值计算方法进行了对比。结果表明，即使在多个共振相关联的情况下，也能取得良好的一致性，从而实现单共振、双共振和三共振系统。这项工作的成果提出了一种经过验证的简化方法，可对侧枝亥姆霍兹谐振器复杂关联中的有效声传播特性进行分析推导。

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引用次数: 0

Broadband vibration reduction of cylindrical shell structures with circumferential taper scatters 利用圆周锥面散射减少圆柱形壳体结构的宽带振动

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-19 DOI: 10.1016/j.jsv.2024.118853

Sen Zhang , Liangzhu Ding , Xinwei Wu , Yongbin Ma , Zichen Deng

In this study, circumferential taper wedges are proposed to reduce broadband vibrations reduction in a circular cylindrical shell. The structural damping characteristics and vibration response of the circular cylindrical shell with circumferential taper wedges are analyzed based on an analytical wave propagation model developed using the symplectic method. The taper wedge is segmented uniformly using a Gaussian discretization method based on the power law, which effectively addresses the non-uniformity of the taper wedge. Meanwhile, the amplitude of each uniform segment is evaluated using the analytical wave propagation model. The accuracy and effectiveness of the homogenization approximation of the analytical model are validated using the finite-element method. Additionally, the forced vibration response and damping characteristics of the circular cylindrical shell, which incorporate both uniform and taper wedges under various boundary conditions, are investigated. The results show that compared with a uniform wedge, the taper wedge provides greater damping, i.e., up to six the damping afforded by a uniform wedge. Despite the relatively short length of the taper wedge, the latter can achieve significant broadband vibration suppression in the host circular cylindrical shell. Additionally, under any boundary condition, the taper wedge can reduce broadband vibrations in the circular cylindrical shell. Finally, the distance between the excitation source and taper wedge significantly affects the vibration attenuation in the circular cylindrical shell.

本研究提出了圆周锥楔来减少圆柱形外壳的宽带振动。根据使用交点法建立的波传播分析模型，分析了带有圆周锥楔的圆柱形壳体的结构阻尼特性和振动响应。锥楔采用基于幂律的高斯离散化方法进行均匀分割，从而有效地解决了锥楔的非均匀性问题。同时，利用解析波传播模型评估了每个均匀段的振幅。使用有限元方法验证了分析模型匀化近似的准确性和有效性。此外，还研究了圆柱形壳体在各种边界条件下的受迫振动响应和阻尼特性，其中包括均匀楔块和锥形楔块。结果表明，与均匀楔块相比，锥形楔块能提供更大的阻尼，即达到均匀楔块阻尼的六倍。尽管锥形楔块的长度相对较短，但后者能在主圆柱形壳体中实现显著的宽带振动抑制。此外，在任何边界条件下，锥楔都能减少圆柱形外壳的宽带振动。最后，激励源与锥楔之间的距离对圆柱形外壳的振动衰减有很大影响。

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引用次数: 0

Dynamically amplified whirling string actuator 动态放大旋弦传动器

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-17 DOI: 10.1016/j.jsv.2024.118826

Igor Berinskii, Slava Krylov

This work introduces a simple, dynamically amplified mechanical actuator incorporating a whirling string (or beam) as an active element. One of the ends of the string is fixed, while another is connected to an elastic spring. The operational principle of the device is based on the nonlinear coupling between the string’s lateral (radial) deflection rotating around the string’s axis and the axial displacement of the string’s end. Such a system may demonstrate a significant mechanical advantage between the force needed to sustain the rotation and the axial force at the string’s end.

这项研究介绍了一种简单的动态放大机械致动器，它将一根旋转的弦（或梁）作为主动元件。弦的一端固定，另一端与弹性弹簧相连。该装置的工作原理基于绕弦轴旋转的弦侧向（径向）挠度与弦端轴向位移之间的非线性耦合。这种系统可以在维持旋转所需的力与弦端轴向力之间显示出明显的机械优势。

引用次数: 0

Investigation of an Impact-buffered Viscous Damper: A new mechanical model, experiments, and numerical simulations 冲击缓冲粘滞阻尼器的研究：新机械模型、实验和数值模拟

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-17 DOI: 10.1016/j.jsv.2024.118852

Yifei Zhang , Yong Ding , Guoshan Xu

This paper introduces a new mechanical model and presents experimental investigations for impact-buffered viscous dampers (IBVDs). A multi-degree-of-freedom bridge system is employed for numerical analysis, investigating the vibration control and impact characteristics of IBVDs. The experimental results closely align with theoretical predictions, with errors of 4.33 % for maximum positive force and 6.73 % for energy dissipation. When the displacement amplitude is greater than or equal to 6 mm, the equivalent viscous damping ratio of the IBVD decreases with the displacement amplitude. Numerical simulations show that IBVDs reduce the maximum acceleration of the girder and the maximum impact force by 20 % and 24 %, respectively. Compared to conventional viscous dampers, IBVDs demonstrate superior vibration control in terms of base shear and girder displacement. An appropriately designed IBVD can dissipate energy comparably to a conventional viscous damper during design-basis earthquakes while also providing enhanced cushioning against sudden collisions in more severe earthquakes.

本文介绍了一种新的机械模型，并对冲击缓冲粘性阻尼器（IBVDs）进行了实验研究。采用多自由度桥梁系统进行数值分析，研究了 IBVD 的振动控制和冲击特性。实验结果与理论预测非常吻合，最大正向力误差为 4.33%，能量耗散误差为 6.73%。当位移振幅大于或等于 6 毫米时，IBVD 的等效粘性阻尼比随位移振幅的增大而减小。数值模拟显示，IBVD 可将大梁的最大加速度和最大冲击力分别降低 20% 和 24%。与传统的粘性阻尼器相比，IBVD 在基底剪切力和大梁位移方面表现出卓越的振动控制能力。在设计基准地震中，设计合理的 IBVD 的消能效果可与传统的粘性阻尼器相媲美，同时还能在更严重的地震中提供更强的缓冲作用，防止突然发生的碰撞。

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引用次数: 0

Evolution of modal properties in the non-proportionally damped coupled vehicle–bridge system 非比例阻尼耦合车桥系统的模态特性演变

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-17 DOI: 10.1016/j.jsv.2024.118803

Shiyi Mei , Daniel Cantero , Colin Caprani

The modal properties of bridges are crucial parameters in engineering applications, and their variation caused by moving vehicles has been increasingly recognized in recent years. However, existing closed-form analytical expressions for the varying modal properties during vehicle passage exist only for simple structural configurations. This paper proposes an innovative method for analyzing the instantaneous modal properties of the system, considering general boundary conditions and the damping effect. First, only general boundary conditions are considered, and the results show that the location of the maximum system frequency shift depends on the mode shape. Then the damping effect is considered, observing that the system is non-proportionally damped in most cases, making it difficult to obtain a closed-form solution using existing methods. To solve this, we transform the system of second-order ordinary differential equations into a set of fourth-order ordinary differential equations and derive the closed-form solution for system’s modal properties. Based on this solution, we introduce the concept of Critical Coupling Damping (CCD), which defines the transition between the coupled description and the moving mass case. This work deepens understanding of changing modal properties during the traverse of sprung masses, and so has numerous potential engineering applications.

桥梁的模态特性是工程应用中的关键参数，近年来，人们越来越认识到移动车辆对其造成的影响。然而，现有的车辆通过时模态特性变化的闭式分析表达式仅适用于简单的结构配置。本文提出了一种分析系统瞬时模态特性的创新方法，同时考虑了一般边界条件和阻尼效应。首先，只考虑一般边界条件，结果表明系统最大频移的位置取决于模态形状。然后考虑阻尼效应，观察到系统在大多数情况下是非比例阻尼的，这使得使用现有方法难以获得闭式解。为了解决这个问题，我们将二阶常微分方程系统转化为一组四阶常微分方程，并推导出系统模态特性的闭式解。在此解的基础上，我们引入了临界耦合阻尼（CCD）的概念，它定义了耦合描述和移动质量情况之间的过渡。这项研究加深了人们对弹簧质量移动过程中模态特性变化的理解，因此在工程应用中具有巨大潜力。

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引用次数: 0

Enhancing gearbox fault diagnosis under phase estimation errors: A dynamic time warping and blind deconvolution approach 加强相位估计误差下的齿轮箱故障诊断：动态时间扭曲和盲解卷方法

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-17 DOI: 10.1016/j.jsv.2024.118851

Taehyung Kim , Jongmin Park , Jinoh Yoo , Jong Moon Ha , Byeng D. Youn

The blind deconvolution technique is widely used to extract subtle fault-related features from the noisy vibration signals of rotating machinery. However, utilizing conventional Minimum Entropy Deconvolution (MED) methods is challenging for analyzing gearboxes, where significant internal and external non-Gaussian disturbance signals are inherent. Although periodicity analysis with signal alignment can be employed to solve this challenge, most available methods require exact phase information for the signals; this must be measured by a specially installed encoder system. To address this issue, this paper introduces a novel method for the fault diagnosis of gearboxes that effectively addresses the significant challenge of extracting periodic fault characteristics from noisy vibration signals, particularly in scenarios characterized by significant phase estimation errors and without the need for an encoder system. By combining the strengths of blind deconvolution with Dynamic Time Warping (DTW)-based sequential signal alignment, our method facilitates the identification and alignment of samples with identical rotational phases. This approach enables the distinction between impulsive features caused by faults and those resulting from noise, thus overcoming the limitations of conventional techniques, which fail to extract periodic fault characteristics under phase estimation errors. The effectiveness of the proposed approach is verified through analytic simulation and experimental validation using data from 2-kW planetary gearbox testbeds at Seoul National University (SNU) and the Korea Research Institute of Standards and Science (KRISS). Results demonstrate the superiority of the proposed method for identifying fault conditions under significant phase estimation errors compared to conventional methods.

盲解卷技术被广泛用于从旋转机械的噪声振动信号中提取与故障相关的微妙特征。然而，利用传统的最小熵解卷积 (MED) 方法分析齿轮箱具有挑战性，因为齿轮箱本身存在大量内部和外部非高斯干扰信号。虽然可以采用信号对齐的周期性分析来解决这一难题，但大多数现有方法都需要信号的精确相位信息；这必须通过专门安装的编码器系统来测量。为解决这一问题，本文介绍了一种用于齿轮箱故障诊断的新方法，它能有效解决从噪声振动信号中提取周期性故障特征这一重大挑战，尤其是在相位估计误差较大的情况下，而且无需编码器系统。我们的方法结合了盲解卷积和基于动态时间扭曲（DTW）的信号顺序对齐的优势，有助于识别和对齐具有相同旋转相位的样本。这种方法能够区分故障引起的脉冲特征和噪声引起的脉冲特征，从而克服了传统技术在相位估计错误的情况下无法提取周期性故障特征的局限性。通过使用首尔国立大学（SNU）和韩国标准与科学研究院（KRISS）的 2 千瓦行星齿轮箱试验台的数据进行分析模拟和实验验证，验证了所提方法的有效性。结果表明，在相位估计误差较大的情况下，与传统方法相比，拟议方法在识别故障条件方面更具优势。

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引用次数: 0