Journal of Sound and Vibration最新文献_第2页

Natural mode splitting of a rotating disc in water at different wall distances as a model for high-head francis runners 水中旋转圆盘在不同壁距下的自然模态分裂作为高水头弗朗西斯流道的模型

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-13 DOI: 10.1016/j.jsv.2024.118824

Xiang Xia , Greco Moraga , Alexandre Presas , Zhengwei Wang , Lingjiu Zhou

Francis turbines are essential equipments in the realm of sustainable energy production. However, their complex dynamics, particularly in the presence of fluid-structure interaction, pose significant challenges to optimising design and enhancing performance. This study focuses on the phenomenon of frequency splitting of a simplified rotating disc submerged in water, serving as a representative model for high-head Francis runners. The primary objective is to gain a deep understanding of how proximity to surrounding walls affects modal parameters of the rotating runner. This research employs both analytical and numerical methods. For cases characterised by significant asymmetry in wall distances on either side of the disc, we have refined the analytical model for frequency splitting based on the assumed mode method and potential flow theory. Additionally, we have developed a numerical model for predicting modal parameters of underwater rotating discs, building upon the imposed modal motion approach. These methods are validated using existing experimental results, demonstrating excellent consistency. The research indicates that for underwater rotating discs, frequency splitting occurs simultaneously with damping splitting. In general, as wall distances decrease, the degree of splitting increases, and the sensitivity of splitting to changes in wall distance also rises. This comprehensive study provides profound insights into the dynamic behavior of high-head Francis runners, highlighting the pivotal role played by wall proximity in shaping their vibrational behavior.

混流式涡轮机是可持续能源生产领域的重要设备。然而，其复杂的动力学特性，尤其是在流固耦合作用下，给优化设计和提高性能带来了巨大挑战。本研究的重点是作为高水头混流式转轮代表模型的浸没在水中的简化旋转盘的频率分裂现象。主要目的是深入了解靠近周围墙壁如何影响旋转流道的模态参数。这项研究采用了分析和数值方法。对于圆盘两侧壁距明显不对称的情况，我们根据假定模态法和势流理论改进了频率分裂的分析模型。此外，我们还在外加模态运动方法的基础上，开发了用于预测水下旋转圆盘模态参数的数值模型。这些方法利用现有的实验结果进行了验证，显示出极好的一致性。研究表明，对于水下旋转盘，频率分裂与阻尼分裂同时发生。一般来说，随着壁距的减小，分频程度会增加，分频对壁距变化的敏感性也会提高。这项全面的研究对高水头混流式转轮的动态行为提供了深刻的见解，突出了壁面距离在影响其振动行为方面所起的关键作用。

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引用次数: 0

Analytical formulae for design of one-dimensional sonic crystals with smooth geometry based on symbolic regression 基于符号回归的光滑几何形状一维声波晶体设计分析公式

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-13 DOI: 10.1016/j.jsv.2024.118821

Viktor Hruška, Aneta Furmanová, Michal Bednařík

Even though locally periodic structures have been studied for more than three decades, the known analytical expressions relating the waveguide geometry and the acoustic transmission are limited to a few special cases. Having an access to numerical model is a great opportunity for data-driven discovery. Our choice of cubic splines to parametrize the waveguide unit cell geometry offers enough variability for waveguide design. Using Webster equation for unit cell and Floquet–Bloch theory for periodic structures, a dataset of numerical solutions was prepared. Employing the methods of physics-informed machine learning, we have extracted analytical formulae relating the waveguide geometry and the corresponding dispersion relation or directly the bandgap widths. The results contribute to the overall readability of the system and enable a deeper understanding of the underlying principles. Specifically, it allows for assessing the influence of the waveguide geometry, offering more efficient alternative to computationally demanding numerical optimization.

尽管对局部周期性结构的研究已有三十多年的历史，但已知的波导几何形状和声波传输的分析表达式仅限于少数特殊情况。获得数值模型是数据驱动发现的绝佳机会。我们选择三次样条来参数化波导单元格的几何形状，为波导设计提供了足够的可变性。利用韦伯斯特单元方程和周期性结构的 Floquet-Bloch 理论，我们编制了一个数值解数据集。利用物理信息机器学习方法，我们提取了波导几何形状与相应色散关系或直接与带隙宽度相关的解析公式。这些结果有助于提高系统的整体可读性，并加深对基本原理的理解。特别是，它允许评估波导几何形状的影响，为计算要求极高的数值优化提供了更有效的替代方法。

引用次数: 0

Stability analysis of nonlinear synchronous vibration in an inclined rotor system supported by journal bearing with variational gravity 具有可变重力的轴颈轴承支撑的倾斜转子系统中非线性同步振动的稳定性分析

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-13 DOI: 10.1016/j.jsv.2024.118835

Li Fan, Tsuyoshi Inoue, Akira Heya

In vertical rotating shaft-bearing systems, synchronous vibration undergoes destabilization and stabilization owing to the self-excited vibration. Recently, these phenomena have been clarified numerically, experimentally, and analytically based on a newly proposed analytical method. In this method, a two-step linearization of the nonlinear journal bearing (JB) force and generalized eigenvalue analysis are proposed to directly determine the stability of the synchronous orbit. However, this method cannot be used directly for inclined-rotor systems with a large gravitational effect. Moreover, stability changes caused by gravity variations in inclined-rotor systems have not been fully investigated. This study extended the analytical method to one with weighted average dynamic coefficients to efficiently predict the stability changes of synchronous whirling vibrations in inclined rotor systems. The extended analytical method clearly clarifies gravity-induced stability changes in comparison with the numerical (shooting) method. Our analytical method enhances the ability of rotor dynamics software to calculate the stability thresholds of inclined rotor systems with gravity variations.

在垂直旋转轴承系统中，同步振动会因自激振动而发生失稳和稳定现象。最近，基于一种新提出的分析方法，对这些现象进行了数值、实验和分析。在该方法中，提出了非线性轴颈轴承（JB）力的两步线性化和广义特征值分析，以直接确定同步轨道的稳定性。然而，这种方法不能直接用于具有较大重力效应的倾斜转子系统。此外，斜转子系统中由重力变化引起的稳定性变化尚未得到充分研究。本研究将分析方法扩展为具有加权平均动态系数的方法，以有效预测倾斜转子系统中同步漩涡振动的稳定性变化。与数值（射击）方法相比，扩展的分析方法清楚地阐明了重力引起的稳定性变化。我们的分析方法提高了转子动力学软件计算有重力变化的倾斜转子系统稳定性阈值的能力。

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引用次数: 0

Improved calculation method for fault characteristic frequency of bearing with local defect on rolling element considering kinematic characteristics of raceways 考虑滚道运动学特性的滚动体局部缺陷轴承故障特征频率改进计算方法

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-12 DOI: 10.1016/j.jsv.2024.118825

Yaofeng Liu, Changfeng Yan, Jianxiong Kang, Yu Tian, Wanglong Chen, Lixiao Wu

The fault characteristic frequency of rolling bearing (RB) is widely used in fault diagnosis, and the theoretical values of fault characteristic frequencies currently used for studying local defect on rolling element (LDRE) are derived based on the self-rotation speed of the rolling element (RE). However, particularly in the case of supporting bearings, the inner raceway is rotated with the shaft while the outer raceway is fixed. This results in different kinematic properties of different raceways in contact with LDRE. Therefore, based on the different types of kinematic characteristics, fault characteristic frequencies of RE contacting with the different raceways have been derived respectively. The proposed frequencies are proved by experiment results and the benchmark data sets of bearing. Because the transmission path generated by LDRE contacting with the outer raceway is shorter than that generated by the inner raceway, the vibration response generated by LDRE contacting the outer raceway are more obvious. Therefore, combining the characteristic frequency of LDRE contacting with the inner raceway(f_FRCI) with that of LDRE contacting with the outer raceway(f_FRCO) can reduce misdiagnosis rate. The proposed f_FRCO and f_FRCI will provide a theoretical foundation for the fault diagnosis and condition monitoring of RBs.

滚动轴承（RB）的故障特征频率被广泛用于故障诊断，目前用于研究滚动体局部缺陷（LDRE）的故障特征频率理论值是基于滚动体（RE）的自转速度得出的。然而，特别是在支撑轴承的情况下，内滚道随轴旋转，而外滚道固定不动。这导致与 LDRE 接触的不同滚道具有不同的运动特性。因此，根据不同类型的运动特性，分别得出了 RE 与不同滚道接触的故障特征频率。实验结果和轴承基准数据集证明了所提出的频率。由于 LDRE 与外滚道接触时产生的传递路径比与内滚道接触时产生的传递路径短，因此 LDRE 与外滚道接触时产生的振动响应更为明显。因此，将 LDRE 与内滚道接触的特征频率（fFRCI）与 LDRE 与外滚道接触的特征频率（fFRCO）相结合，可以降低误诊率。提出的 fFRCO 和 fFRCI 将为 RB 的故障诊断和状态监测提供理论基础。

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引用次数: 0

A displacement formulation for coupled elastoacoustic problems that preserves flow irrotationality 保留流动不旋转性的耦合弹声问题位移公式

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-10 DOI: 10.1016/j.jsv.2024.118815

Jie Deng , Oriol Guasch , Laurent Maxit

Two-way fluid–structure interaction (FSI) problems, in the sense that a flow induces the motion of a solid, which in turn modifies the flow boundary conditions, have been approached with very different strategies, the most common of which is probably the finite element method (FEM). In the case of elastoacoustics, the flow consists of an acoustic field interacting with a vibrating structure. When the problem is discretized with the FEM, an algebraic block matrix system is obtained and the coupling between the acoustic field and the structure takes place through a coupling matrix with off-diagonal terms. Usually the structure is characterized by its displacement field, while for the acoustics several options are available, ranging from pressure to acoustic displacement or velocity/displacement acoustic potentials. Depending on the formulation, symmetric or asymmetric systems are obtained and different types of numerical stability problems have to be faced. In this work, a monolithic strategy based on the Rayleigh–Ritz method is proposed. The displacement is used as the primary variable for both the structure and the acoustic field and is expanded in terms of Gaussians as basis functions. This provides an algebraic block matrix system for the global uncoupled problem. However, instead of resorting to a coupling matrix, the essential continuity conditions at the acoustic-structure interface are imposed by the nullspace method (NSM). That is, the solution of the uncoupled system is expanded in terms of a basis of the nullspace generated by the essential conditions of the problem, including the displacement continuity constraints at the interface, thus giving the solution of the coupled problem. As for natural conditions, they are imposed in a weak sense. For ease of explanation, a one-dimensional (1D) case is first introduced, followed by the coupling of a 2D acoustic cavity with a beam and a 3D one with a plate. The proposed method is validated with FEM simulations on fine meshes and the advantage of using Gaussian basis functions over trigonometric ones is also demonstrated.

对于双向流固耦合（FSI）问题，即流动引起固体运动，而固体运动又改变流动边界条件的问题，人们采用了多种不同的方法，其中最常用的可能是有限元法（FEM）。在弹性声学中，流动由声场与振动结构相互作用组成。当使用有限元法对问题进行离散化处理时，会得到一个代数分块矩阵系统，声场与结构之间的耦合是通过一个带对角项的耦合矩阵实现的。结构通常以其位移场为特征，而声学则有多种选择，包括压力、声位移或速度/位移声势。根据公式的不同，会得到对称或不对称的系统，并面临不同类型的数值稳定性问题。在这项工作中，提出了一种基于 Rayleigh-Ritz 方法的整体策略。位移被用作结构和声场的主变量，并以高斯作为基函数展开。这就为全局非耦合问题提供了一个代数分块矩阵系统。不过，在声学-结构界面上的基本连续性条件不是通过耦合矩阵，而是通过无效空间法（NSM）来实现的。也就是说，非耦合系统的解是根据问题的基本条件（包括界面上的位移连续性约束）生成的无效空间的基础展开的，从而得到耦合问题的解。至于自然条件，它们是在弱意义上施加的。为便于解释，首先介绍一维（1D）情况，然后是二维声腔与梁的耦合和三维声腔与板的耦合。所提出的方法通过精细网格上的有限元模拟进行了验证，并证明了使用高斯基函数比使用三角函数的优势。

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引用次数: 0

Hysteretic tuned mass damper with bumpers for seismic protection: Modeling, identification, and shaking table tests 用于抗震保护的带缓冲器的滞回调谐质量阻尼器：建模、识别和振动台试验

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-09 DOI: 10.1016/j.jsv.2024.118816

Vinay Yadav Janga , Pranath Kumar Gourishetty , Biagio Carboni , Giuseppe Quaranta , Walter Lacarbonara

A nonlinear tuned mass damper (TMD) is proposed for seismic retrofitting of buildings. The TMD consists of steel wire ropes that, on one end, are fixed to an oscillating mass, on the other end, they are connected to the main structure by means of a special clamping system based on a double sliding mechanism. The device is equipped with bumpers that provide an additional source of energy dissipation. Experimental dynamic tests aimed to investigate the TMD nonlinear response are discussed. The experimental results unfolding a peculiar pinched hysteretic behavior with almost zero stiffness around the origin are accurately simulated according to a novel phenomenological model. Several shaking table tests are conducted on a laboratory-scale building prototype equipped with the proposed device on the top floor. A comparison between experimental results from shaking table tests and those obtained from numerical simulations is documented to demonstrate the robustness of the proposed nonlinear TMD performance and the accuracy of the numerical model driving its optimization. A critical analysis is also performed taking into account experimental results available in the literature based on shaking table tests conducted on different vibration control devices.

为建筑物的抗震改造提出了一种非线性调谐质量阻尼器（TMD）。TMD 由钢丝绳组成，钢丝绳的一端固定在一个振动质量上，另一端通过一个基于双滑动机构的特殊夹紧系统与主体结构相连。该装置配备有缓冲器，可提供额外的能量消耗源。本文讨论了旨在研究 TMD 非线性响应的实验动态测试。实验结果展示了一种奇特的挤压滞后行为，在原点附近的刚度几乎为零，并根据一种新的现象学模型进行了精确模拟。在实验室规模的建筑原型上进行了多次振动台试验，该建筑原型的顶层安装了所提出的装置。记录了振动台试验结果与数值模拟结果之间的比较，以证明所提议的非线性 TMD 性能的稳健性以及推动其优化的数值模型的准确性。此外，还参考了文献中基于不同振动控制装置的振动台试验得出的实验结果，进行了批判性分析。

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引用次数: 0

Parameter optimization of tuned inerter damper for vibration suppression in structures with damping 用于抑制带阻尼结构振动的调谐插入式阻尼器的参数优化

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-08 DOI: 10.1016/j.jsv.2024.118827

Shaowei Tong , Jinming Zeng , Zhizhi Miao , Guo Chen

This study investigates the parameter optimization of tuned inerter damper (TID) in a single degree of freedom (SDOF) system, with a focus on vibration mitigation. As a type of inerter based dynamic vibration absorber (IDVA), TID achieves vibration suppression of the primary structure by replacing the mass block in traditional dynamic vibration absorber (DVA) with an inerter, thereby minimizing the increase in physical mass. With the displacement response of the primary structure as the objective function, this study first employs the classical fixed point theory (FPT) to derive the analytical formulations for the optimal parameters of TID following the

H_{\infty}

optimization approach and neglecting the inherent damping of primary structure. The influence of optimal parameter deviations on the vibration mitigation effect of TID is also analyzed, revealing that the deviation of the optimal natural frequency ratio has a significant impact on the vibration mitigation performance. By flattening the amplitude curve of the displacement transfer function of primary structure between the fixed points, this study derives the analytical solution for the optimal damping ratio of TID using the extended fixed point theory (EFPT). When the inherent damping of primary structure is considered, this study employs the approximate extended fixed point theory (AEFPT) to derive the approximate optimal parameters of TID. A comparative study of the optimal natural frequency ratios obtained using FPT, AEFPT and numerical searches reveals that the discrepancies among the three methods are minimal for structures with low inherent damping. However, as the inherent damping ratio of the primary structure increases, the optimal natural frequency ratio obtained using FPT deviates significantly from the exact value, whereas the approximate optimal natural frequency ratio derived using AEFPT can significantly reduce this deviation. Combining the conclusion that the vibration mitigation effect of TID is significantly influenced by the natural frequency ratio, this study suggests that for highly damped primary structures, the use of AEFPT can yield more optimal TID parameters, thereby enhancing the robustness of vibration mitigation performance.

本研究探讨了单自由度（SDOF）系统中调谐插入式阻尼器（TID）的参数优化问题，重点关注振动缓解问题。作为一种基于插入式阻尼器的动态吸振器（IDVA），TID 通过用插入式阻尼器取代传统动态吸振器（DVA）中的质量块来实现主结构的振动抑制，从而最大限度地减少物理质量的增加。以主结构的位移响应为目标函数，本研究首先采用经典的定点理论（FPT），按照 H∞ 优化方法并忽略主结构的固有阻尼，推导出 TID 最佳参数的解析公式。同时分析了最优参数偏差对 TID 减振效果的影响，发现最优固有频率比的偏差对减振性能有显著影响。本研究利用扩展定点理论（EFPT），通过对主结构在定点间的位移传递函数幅值曲线进行平移，得出了 TID 最佳阻尼比的解析解。当考虑到主结构的固有阻尼时，本研究采用近似扩展定点理论（AEFPT）推导出 TID 的近似最优参数。通过对使用 FPT、AEFPT 和数值搜索获得的最佳固有频率比进行比较研究发现，对于固有阻尼较低的结构，三种方法之间的差异很小。然而，随着主结构固有阻尼比的增加，使用 FPT 得出的最佳固有频率与精确值偏差很大，而使用 AEFPT 得出的近似最佳固有频率则能显著减少这种偏差。结合 TID 的减振效果受固有频率的显著影响这一结论，本研究表明，对于高阻尼主结构，使用 AEFPT 可以获得更优化的 TID 参数，从而提高减振性能的稳健性。

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引用次数: 0

A nonlinear dual-mode active vibration controller for hardening systems and its experimental application to a beam 用于硬化系统的非线性双模主动振动控制器及其在梁上的实验应用

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-08 DOI: 10.1016/j.jsv.2024.118823

Celia Hameury , Giovanni Ferrari , Marco Amabili

The control of nonlinear vibrations, such as those arising from geometric nonlinearities and large amplitude, has often been limited to the first natural mode. In this work, a novel nonlinear dual-mode multiple-input multiple-output (MIMO) positive position feedback (PPF) controller is presented and tested experimentally on a clamped composite sandwich beam subject to a stepped-sine-excitation with increasing force excitation levels in the frequency neighbourhood of the first and second natural frequencies. This nonlinear controller contains two linear PPF controllers, targeting the first and second natural frequencies, each one augmented with a cubic term designed to counter the hardening behaviour of the test structure. Control parameters were chosen by optimizing the vibration reduction observed at low excitation amplitudes. The nonlinear dual-mode MIMO controller was compared to a single-input single-output version, and to a linear version in which the cubic terms were removed. The nonlinear dual-mode MIMO was shown to outperform both. A linear dual-mode MIMO controller was compared to two linear single-mode MIMO controllers, targeting the first and second mode respectively, and was found to outperform both when applied to the first mode. The effect of varying the nonlinear cubic term of the nonlinear dual-mode MIMO controller was also investigated, indicating better vibration reduction for higher cubic terms, up to some values. Overall, this study shows that a nonlinear dual-mode MIMO PPF controller is the preferred option for controlling the first two modes of the beam under study.

非线性振动（如几何非线性和大振幅引起的振动）的控制通常仅限于第一自然模态。本研究提出了一种新型非线性双模多输入多输出（MIMO）正位置反馈（PPF）控制器，并在夹紧的复合材料夹层梁上进行了实验测试，该梁受到阶梯正弦激励，在第一和第二固有频率的频率邻域内，力激励水平不断增加。该非线性控制器包含两个线性 PPF 控制器，分别针对第一和第二固有频率，每个控制器都增加了一个立方项，以抵消测试结构的硬化行为。控制参数是通过优化在低激励振幅下观察到的减振效果来选择的。非线性双模 MIMO 控制器与单输入单输出版本以及去掉立方项的线性版本进行了比较。结果表明，非线性双模多输入多输出控制器的性能优于这两种控制器。将线性双模式 MIMO 控制器与分别针对第一和第二模式的两个线性单模式 MIMO 控制器进行了比较，发现在应用于第一模式时，线性双模式 MIMO 控制器的性能优于这两个控制器。此外，还研究了改变非线性双模 MIMO 控制器的非线性立方项的效果，结果表明，当立方项达到一定值时，立方项越大，减振效果越好。总之，这项研究表明，非线性双模 MIMO PPF 控制器是控制所研究梁的前两个模态的首选方案。

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引用次数: 0

Damage identification of mono-coupled periodic structures based on driving-point anti-resonance frequency and sensitivity analysis 基于驱动点反共振频率和灵敏度分析的单耦合周期结构损伤识别

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-07 DOI: 10.1016/j.jsv.2024.118819

Hongping Zhu, Ying Zhang, Shun Weng

Anti-resonance frequencies are advantageous for structural damage identification because they are sensitive to local damage and can be easily measured. Sensitivity-based methods for identifying damage rely on the precision of the structural analytical model, which is typically difficult to achieve. Therefore, a damage-identification method that requires only anti-resonance frequencies without any detailed information regarding the model is appealing. This study presents a method for damage identification in periodic structures based on driving-point anti-resonance frequency and sensitivity analysis. The relative sensitivity of the anti-resonance frequency to individual elemental parameters is derived. This sensitivity is related only to the total number of periodic elements, element location, and driving-point location, and is not affected by the specific geometric or physical parameters of the structure. The proposed method was applied to a periodic mass–spring system and a multistory frame for damage identification. Accurate damage identification can be achieved by utilizing driving-point anti-resonance frequencies.

反共振频率对于结构损伤识别很有优势，因为它们对局部损伤很敏感，而且很容易测量。基于灵敏度的损伤识别方法依赖于结构分析模型的精度，而这通常很难实现。因此，一种只需要反共振频率而不需要任何有关模型详细信息的损伤识别方法很有吸引力。本研究提出了一种基于驱动点反共振频率和灵敏度分析的周期结构损伤识别方法。研究得出了反共振频率对单个元素参数的相对敏感性。该灵敏度仅与周期元素总数、元素位置和驱动点位置有关，而不受结构特定几何或物理参数的影响。所提出的方法被应用于周期性质量弹簧系统和多层框架的损伤识别。通过利用驱动点反共振频率，可以实现精确的损伤识别。

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引用次数: 0

Assessing the quality of the time delay estimate in acoustic leak localisation 评估声学泄漏定位中时间延迟估计的质量

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-07 DOI: 10.1016/j.jsv.2024.118811

Ndubuisi Uchendu, Jennifer M. Muggleton, Paul R. White

The problem considered in this paper is assessing the quality of the time delay estimate between leak signals measured on water pipes. This is practically important, as a quantitative assessment of the accuracy of time delay estimation (TDE) results makes it possible to infer the reliability of acoustic leak localisation results in a given situation. Three quality assessment approaches are developed by considering the statistical properties of the cross-correlation function (CCF): information-criterion, processing gain, and statistical approaches. In the information-criterion approach, the Bayes factor (BF) is employed to decide the most likely probability distribution of observed CCF peak values. The processing gain approach determines the quality of the time delay estimate using indices that indicate detectability of the CCF peak, namely, the peak-to-side lobe ratio (PSR) and the peak-to-mean ratio (PMR). In the statistical approach, an index termed inconsistency score (ICS) is used to describe the quality of TDE results based on root-mean square of deviations of time delay estimates from their statistical mode. Experimental results show that the proposed approaches provide effective means of assessing the accuracy of the time delay estimate in acoustic leak detection applications. Also, the proposed indices can be employed as figures of merit for selecting best parameters for TDE, for example, filter cut-off frequencies.

本文考虑的问题是评估在水管上测量到的泄漏信号之间的时延估计质量。这一点具有重要的实际意义，因为通过对时延估计（TDE）结果的准确性进行定量评估，可以推断出在特定情况下声学泄漏定位结果的可靠性。通过考虑交叉相关函数 (CCF) 的统计特性，开发了三种质量评估方法：信息标准、处理增益和统计方法。在信息标准方法中，贝叶斯因子（BF）被用来决定观测到的 CCF 峰值最可能的概率分布。处理增益法使用表示 CCF 峰值可探测性的指数（即峰值与侧叶比率 (PSR) 和峰值与平均值比率 (PMR)）来确定时延估计的质量。在统计方法中，一种称为不一致性得分（ICS）的指数被用来描述基于时间延迟估计值偏离其统计模式的均方根的 TDE 结果质量。实验结果表明，在声学泄漏检测应用中，所提出的方法为评估时延估计的准确性提供了有效手段。此外，所提出的指数还可用作选择 TDE 最佳参数（如滤波器截止频率）的优点指数。

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引用次数: 0