Journal of Sound and Vibration最新文献_第7页

Raw sensor data fusion using Johansen cointegration for condition assessment of concrete poles

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-12-13 DOI: 10.1016/j.jsv.2024.118909

Mohsen Mousavi , Ulrike Dackermann , Sahar Hassani , Mahbube Subhani , Amir H. Gandomi

This paper presents a novel approach for raw sensor data fusion using Johansen cointegration, aimed at non-destructive condition assessment of concrete poles. The proposed Johansen cointegration-based signal fusion is compared with signal averaging, a conventional method, and the Adaptive Kalman Filter (AKF), an advanced signal fusion technique. These methods are applied to data collected from concrete poles under both laboratory and real-world field conditions, using an innovative narrow-band stress wave excitation system with a center frequency of 1 kHz. Our methodology begins with fusing raw sensor data, which is subsequently decomposed into narrow-band components, known as Intrinsic Mode Functions (IMFs), using the Variational Mode Decomposition (VMD) algorithm. From these IMFs, we extract a set of non-parametric and parametric statistical features based on Instantaneous Frequency (IF) and Instantaneous Amplitude (IA) signals. The results demonstrate the superiority of Johansen cointegration over both signal averaging and AKF in scenarios involving the high nonstationarity characteristic of real-world field data. Furthermore, the findings highlight a notable similarity between AKF and signal averaging, which may reflect the dominant linear properties in the recorded signals. We also propose an index based on normalized mutual information to facilitate a fair comparison with existing fusion methods.

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引用次数: 0

Stability analysis of shimmy under the consideration of tire pavement contact mechanics behavior

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-12-13 DOI: 10.1016/j.jsv.2024.118916

Shuang Ruan , Ming Zhang , Xiazheng Shi , Xinyu Liu , Hong Nie

The analysis and research on shimmy stability are generally based on established tire parameters and flat and rigid pavement models. Modern aircraft taxiing requires verification and comprehensive evaluation in combination with landing gear shimmy physical tests and special scenario flight tests. The size of tire imprints affects the dynamic characteristics of tires, and empirical formulas do not take into account the contour shape and contact surface state of tires. At the same time, the study and analysis of shimmy often overlook the influence of pavement curvature. Based on this, in order to study the mutual influence of tire contact deformation and pavement curvature on shimmy stability, this paper takes the landing gear system as the research object, combines shimmy analysis methods, line contact models, and point contact models, and establishes a shimmy analysis model that considers the elastic-plastic deformation of tire pavement contact. The accuracy of the theoretical model is verified through imprint tests, and deviation coefficients are introduced to analyze the differences in shimmy response results between traditional models and contact models. The results show that the new tire deformation theory can better fit the test data and consider the effects of tire configuration, grooves, and contact surface curvature; The tire imprints obtained by different algorithms have certain differences, and tire imprints have a significant impact on the stability of shimmy; The critical damping deviation required for anti shimmy of the landing gear system decreases with the increase of the ratio of flywheel to tire radius, and can reach a deviation of over 20% for both point contact and line contact models; Ensuring that the tire has the same imprint length and the same compression amount will result in deviations in the evaluation of the stability analysis of the shimmy, and the results of the shimmy test bench need to be corrected.

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引用次数: 0

On the modeling of imperfect interfaces in multilayers with Transfer Matrix Method

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-12-09 DOI: 10.1016/j.jsv.2024.118898

Fabien Marchetti, Fabien Chevillotte

Multilayer systems are widely used in industry for their performances as compared with homogeneous materials. The layers are usually glued together but the bonding may be imperfect (air bubble, detachment). The interfaces are generally modeled as sliding or bonded. These two behaviors can be significantly different and the actual behavior is generally somewhere in between. The vibroacoustic behavior of the structure is thus modified by the imperfect interface. Several models have been implemented to describe the dynamic behavior of multilayer systems with imperfect interfaces. In this paper, an analytical model of imperfect interfaces based on the Transfer Matrix Method (TMM) is developed. Two computations are performed in parallel (one with a perfectly bonded interface and the other with a sliding interface). Then, the global transfer matrix obtained from each computation are mixed together. The main novelty of this paper lies in the use of a new mixing method which is applied on the state variables as compared with existing methods which are applied on impedances or admittances matrices. This new method is compared in terms of sound absorption or sound transmission loss with the existing ones and is applied on different classical multilayer systems with multi-layered solid plates and a multilayer composed of a porous layer with a heavy layer which is widely used in the automotive industry.

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引用次数: 0

A dual-mode hybrid magnetic high-static-low-dynamic stiffness vibration isolator

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-12-09 DOI: 10.1016/j.jsv.2024.118906

Ming Zhang , Hongtao Li , Lei Zhang , Feng Sun , Xingwei Sun , Koichi Oka

A high-static-low-dynamic stiffness (HSLDS) vibration isolator with both semi-active and passive operating modes is presented. This vibration isolator is designed using three permanent magnets (PMs) and two coil windings (CWs). The HSLDS characteristics arise from the nonlinear repulsive forces between the PMs. The stiffness characteristics of the system can be rapidly adjusted by regulating the current in the CWs. When the current is set to zero, the system transitions from semi-active to passive mode. Unlike traditional vibration isolation systems that utilize linear springs to balance load forces, this proposed system relies on the repulsive forces between PMs, resulting in asymmetric stiffness characteristics. This design ensures a more compact structure while maintaining the HSLDS properties even in passive mode. This paper establishes a nonlinear axial magnetic force model and dynamic equations for the system. Based on Floquet theory, the stability of the nonlinear system is analyzed, and the stability boundaries are identified. The impact of geometric parameters on vibration isolation performance is examined, and optimal parameters are selected to construct the experimental setup. The experimental results validate the vibration isolation performance of the device. Based on the analysis of the experimental data, a semi-active control strategy that incorporates frequency calculations is proposed in this study. Finally, the effectiveness of the semi-active control strategy in enhancing vibration isolation performance is confirmed through additional experiments.

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引用次数: 0

Two-stage Bayesian inference for rail model updating and crack detection with ultrasonic guided wave measurements and advanced wave propagation simulation

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-12-08 DOI: 10.1016/j.jsv.2024.118914

Jiang-Zheng Zhan , Wang-Ji Yan , Wen Wu , Ka-Veng Yuen , Dimitrios Chronopoulos

Ultrasonic Guided Waves (UGWs) play a vital role in the non-destructive testing due to exceptional sensitivity to small damage. This study proposes an integrated two-stage Bayesian inference scheme, aimed at updating the physical model parameters of the rail, to improve subsequent crack identification, thus overcoming the limitations caused by insufficient crack detection due to modeling discrepancies. Within the integrated two-stage Bayesian inference framework, the physical model parameters (i.e., modulus of elasticity and damping loss factor, etc.) are updated using wavenumbers extracted from UGW measurements. Subsequently, the crack parameters are identified based on scattering coefficients predicted by the updated forward solver. An integral formula is ultimately derived analytically to incorporate the uncertainty propagation procedure from the physical model parameters into the crack parameter identification, properly accounting for the model parameter variability. Additionally, a Monte Carlo simulation is employed to approximate the integral. To address the computational challenges in the likelihood evaluations during the Bayesian inversion procedure using Transitional Markov Chain Monte Carlo (TMCMC) in both stages, a cost-effective Kriging predictor providing a surrogate mapping between the model predictions and the identified parameters is established for each stage based on the training outputs computed using an advanced wave propagation simulation scheme. The feasibility and effectiveness are verified through numerical and experimental investigations. Results indicate that the proposed Bayesian inference scheme based on UGWs in conjunction with the wave propagation simulation-aided metamodel can identify the location and size of the crack with reasonable accuracy and efficiency. The proposed scheme could result in more reliable models effectively enhancing the accuracy of crack identification.

{"title":"Two-stage Bayesian inference for rail model updating and crack detection with ultrasonic guided wave measurements and advanced wave propagation simulation","authors":"Jiang-Zheng Zhan , Wang-Ji Yan , Wen Wu , Ka-Veng Yuen , Dimitrios Chronopoulos","doi":"10.1016/j.jsv.2024.118914","DOIUrl":"10.1016/j.jsv.2024.118914","url":null,"abstract":"<div><div>Ultrasonic Guided Waves (UGWs) play a vital role in the non-destructive testing due to exceptional sensitivity to small damage. This study proposes an integrated two-stage Bayesian inference scheme, aimed at updating the physical model parameters of the rail, to improve subsequent crack identification, thus overcoming the limitations caused by insufficient crack detection due to modeling discrepancies. Within the integrated two-stage Bayesian inference framework, the physical model parameters (i.e., modulus of elasticity and damping loss factor, etc.) are updated using wavenumbers extracted from UGW measurements. Subsequently, the crack parameters are identified based on scattering coefficients predicted by the updated forward solver. An integral formula is ultimately derived analytically to incorporate the uncertainty propagation procedure from the physical model parameters into the crack parameter identification, properly accounting for the model parameter variability. Additionally, a Monte Carlo simulation is employed to approximate the integral. To address the computational challenges in the likelihood evaluations during the Bayesian inversion procedure using Transitional Markov Chain Monte Carlo (TMCMC) in both stages, a cost-effective Kriging predictor providing a surrogate mapping between the model predictions and the identified parameters is established for each stage based on the training outputs computed using an advanced wave propagation simulation scheme. The feasibility and effectiveness are verified through numerical and experimental investigations. Results indicate that the proposed Bayesian inference scheme based on UGWs in conjunction with the wave propagation simulation-aided metamodel can identify the location and size of the crack with reasonable accuracy and efficiency. The proposed scheme could result in more reliable models effectively enhancing the accuracy of crack identification.</div></div>","PeriodicalId":17233,"journal":{"name":"Journal of Sound and Vibration","volume":"599 ","pages":"Article 118914"},"PeriodicalIF":4.3,"publicationDate":"2024-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143152687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An asymmetric hysteresis model for metal-rubber isolators under dynamic loading and its application to nonlinear vibration simulation

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-12-07 DOI: 10.1016/j.jsv.2024.118911

Yihan Du , Dong Wang , Yongbu Jin , Xuanhua Fan

Metal-rubber isolators (MRIs) have been widely used to mitigate vibration in sensitive equipment due to their high damping properties. This paper aims to predict the nonlinear vibration response of an MRI system by using the hysteretic nonlinearity of a single MRI. An experimental study was conducted to investigate the effects of excitation levels on the hysteretic nonlinearities of a typical MRI. An asymmetric hysteresis model (AHM) was developed to accurately reproduce the experimental hysteresis loop by simultaneously considering the nonlinear elasticity and dry friction damping. The equivalent slip force amplitude of the MRI can be extracted from the frictional damping force to describe the slip state of the internal metal wires. Additionally, it was integrated as a constraint into parameter evolution to accurately predict the hysteretic behavior at various excitation amplitudes. The harmonic balance method (HBM) combined with alternating frequency-time (AFT) analysis was used to simulate the steady-state nonlinear vibration response of a complex MRI system. The simulation results showed good agreement with the experimental data, and indicated two major nonlinear phenomena: nonlinear softening stiffness and nonlinear damping effects. This paper developed a modeling and simulation strategy spanning from the MRI element to the system level.

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引用次数: 0

The Maximally-Coherent Reference technique and its application to sound source extraction without synchronous measurements

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-12-07 DOI: 10.1016/j.jsv.2024.118896

Muhammad N. Albezzawy, Jérôme Antoni, Quentin Leclère

In source identification, it is often necessary to perform source extraction, and in cases involving sequential measurements, to also perform resynchronization. Coherence techniques, which are based on the use of references (i.e., fixed sensors), are widely used to solve these two equivalent problems. However, when the number of references surpasses the number of sources, the cross-spectral matrix becomes ill-conditioned, invalidating the popular least squares (LS) solution. Although the truncated singular value decomposition (TSVD) was successfully applied in the literature to solve this problem, its validity is limited to the case of scalar noise on the references. It is also difficult to apply, when the singular values are gradually decreasing. This paper proposes a solution based on a set of virtual references that is maximally correlated with the measurements, named the Maximally-Coherent Reference (MCR) technique, accompanied with a technique for estimating the number of sources. The method is validated using both numerical and physical laboratory experiments, and by using real acoustical data from an e-motor. It is shown to return better results than LS and TSVD when employed for the same purpose.

{"title":"The Maximally-Coherent Reference technique and its application to sound source extraction without synchronous measurements","authors":"Muhammad N. Albezzawy, Jérôme Antoni, Quentin Leclère","doi":"10.1016/j.jsv.2024.118896","DOIUrl":"10.1016/j.jsv.2024.118896","url":null,"abstract":"<div><div>In source identification, it is often necessary to perform source extraction, and in cases involving sequential measurements, to also perform resynchronization. Coherence techniques, which are based on the use of references (i.e., fixed sensors), are widely used to solve these two equivalent problems. However, when the number of references surpasses the number of sources, the cross-spectral matrix becomes ill-conditioned, invalidating the popular least squares (LS) solution. Although the truncated singular value decomposition (TSVD) was successfully applied in the literature to solve this problem, its validity is limited to the case of scalar noise on the references. It is also difficult to apply, when the singular values are gradually decreasing. This paper proposes a solution based on a set of virtual references that is maximally correlated with the measurements, named the Maximally-Coherent Reference (MCR) technique, accompanied with a technique for estimating the number of sources. The method is validated using both numerical and physical laboratory experiments, and by using real acoustical data from an e-motor. It is shown to return better results than LS and TSVD when employed for the same purpose.</div></div>","PeriodicalId":17233,"journal":{"name":"Journal of Sound and Vibration","volume":"599 ","pages":"Article 118896"},"PeriodicalIF":4.3,"publicationDate":"2024-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143152686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Optimal bearing configuration selection for power generation shaft-trains: A linear and nonlinear dynamics approach

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-12-06 DOI: 10.1016/j.jsv.2024.118907

Athanasios Chasalevris , Ioannis Gavalas , Jerzy T. Sawicki

This paper proposes a straightforward procedure for defining bearing design configurations in turbine-generator shaft trains. The bearing design inputs specify the bearing type and the pad configuration. The design outputs focus on stability, bearing integrity, and operability of the shaft-train system. The design output is evaluated in two ways: a) linear harmonic analysis utilizing linearized stiffness and damping coefficients for the bearing impedance forces, and b) nonlinear analysis, where the bearing forces are modeled as nonlinear functions of bearing and pedestal kinematics; the response is evaluated by collocation-type method coupled with numerical continuation. Thermohydrodynamic lubrication (THD lubrication) with turbulence correction is considered in the bearing lubrication model.

The results show that all constraints are satisfied, and the optimal bearing configurations include preload and offset, while no specific trend is observed for specific loads. Laminar oil flow is prompted by the optimization through specific bearing diameters. Linear and nonlinear dynamic models do not render identical optimal designs. Linear model tends to be conservative in the design output, while nonlinear dynamic model provides more accurate predictions, accounting for any whirling orbit shape. The results emphasize the necessity of incorporating nonlinear dynamics into standard rotor dynamic calculations for this type of machines.

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引用次数: 0

Study on vertical-torsional chatter under asymmetric conditions in tandem cold rolling

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-12-05 DOI: 10.1016/j.jsv.2024.118888

Fangsheng Chen , Xu Li , Lei Cao , Pengfei Wang

The vibrations generated by the rolling mills significantly impair the production quality and efficiency of cold tandem rolling. Considering that the main drive system constitutes one of the energy sources of vibration, this study integrates the vertical structure of the rolling mill with the torsional structure of the main drive system for a comprehensive analysis. This study establishes an asymmetric dynamic rolling force model that accounts for the structural asymmetry of the rolling mill, the asymmetric power transmission between the upper and lower connecting shafts of the main drive system, and the long-term wear and friction conditions of the mechanical equipment. Furthermore, this study accounts for the speed differential between the upper and lower work rolls induced by torsional vibrations. Based on these interdependent parameters, this study develops a rolling mill vibration coupling model to comprehensively assess stability. The validation of the model confirms its high accuracy. Variations in rolling torque under different roll speed ratios, friction coefficient ratios, and roll diameter ratios were analyzed, along with the impact of the cross-shear zone's proportion on system stability under key rolling parameters. Furthermore, changes in rolling torque, amplitude, and the cross-shear zone during unstable operating conditions were examined. Finally, the interaction between the vertical and torsional structures was studied, providing a theoretical foundation for optimizing process parameters and mitigating vibrations in the continuous cold rolling process.

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引用次数: 0

Second and third harmonic generation of acoustic waves in a nonlinear elastic solid in one space dimension

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-12-05 DOI: 10.1016/j.jsv.2024.118895

Fernando Lund

The generation of second and third harmonics by an acoustic wave propagating along one dimension in a weakly nonlinear elastic medium is analyzed by successive approximations starting with the linear case. The medium is loaded harmonically in time with frequency

ω_{0}

at a single point in space. It is important to recall two known facts: The first, nonlinear waves have a speed of propagation that depends on their amplitude, a reflection of the fact that nonlinear oscillators have an amplitude-dependent period. The second fact is that although both a free and a loaded medium generate higher harmonics, the second harmonic of the free medium scales like the square of the linear wave, but this is no longer the case when the medium is externally loaded. The shift in speed of propagation due to the nonlinearities is determined imposing that there be no resonant (“secular”) terms in a successive approximations solution scheme to the homogeneous (i.e., “free”) problem. The result is then used to solve the inhomogeneous (i.e., “loaded”) case also by successive approximations, up to the third order. At second order, the result is a second harmonic wave whose amplitude is modulated by a long wave of wavelength inversely proportional to the shift in the speed of propagation of the linear wave due to nonlinearities. The amplitude of the long modulating wave scales like the amplitude of the linear wave to the four-thirds. It depends both on the third- and fourth-order elastic constants, as well as on the frequency and amplitude of the loading. A distance scale emerges: it depends on nonlinearities, on the loading frequency and on the amplitude of the linear wave. In this distance scale, at short distances from the source a second harmonic scaling proportional to the amplitude of the linear wave squared, and to the distance from the source, is recovered. It depends on the third-order elastic constant only. The third order solution is the sum of four amplitude-modulated waves, two of them oscillate with frequency

ω_{0}

and the other two, third harmonics, with

3 ω_{0}

. In each pair, one term scales like the amplitude of the linear wave to the five-thirds, and the other to the seven-thirds.

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引用次数: 0