Journal of Sound and Vibration最新文献_第8页

Realization of a wideband three-axis horizontal vibration isolator with adjustable stiffness and damping

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-12-04 DOI: 10.1016/j.jsv.2024.118876

Mehmet Utku Demir, Cetin Yilmaz

Horizontal vibration isolators (HVIs) designed to be on the verge of elastic instability offer many opportunities for isolating a variety of vibration-sensitive instruments, such as atomic force microscopes and laser/optical systems from ambient excitations at very low frequencies (0.5 – 5 Hz). These HVI systems are designed to have very low natural frequencies and can achieve quasi-zero-stiffness (QZS) in the horizontal axes when they support payloads close to their maximum payload-carrying capacities. Payloads of different sizes and weights necessitate to have adjustable stiffness and damping to operate in very wide bandwidths. To address these issues, a QZS HVI using axially compressed elastic columns is designed, optimized and fabricated. The system has adjustable natural frequencies in three axes (two translational and one torsional) via a string tensioning mechanism. Besides, the system enables the torsional natural frequency to be adjusted independently of the two translational natural frequencies by means of novel column sliding mechanisms that can change the radial positions of the elastic columns from the center axis of the system. Amplitude-dependent damping and stiffness characteristics of this variable natural frequency system are determined under various axial preload conditions. The system also involves an adjustable eddy current damper to effectively suppress low frequency resonance peaks. Finally, a methodology is proposed to modify the ideally clamped boundary conditions of the elastic columns, resulting in very good agreement between the analytical, numerical, and experimental results. The results show that the proposed HVI can achieve bandwidths between 1.6 – 311 Hz in the translational axes and 0.7 – 311 Hz in the torsional axis for payloads between 0 – 45 kg, providing a very large isolation bandwidth in three axes for a wide range of payload masses.

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引用次数: 0

Three-dimensional interaction of thermoacoustic modes in a circular tube

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-12-04 DOI: 10.1016/j.jsv.2024.118899

Weipeng Zhou , Xiaoyu Wang , Guangyu Zhang , Maria Heckl , Xiaofeng Sun

This study applies the Green's function method to investigate the modal interaction during thermoacoustic instability specifically in the afterburner. The afterburner is modelled as a cylindrical tube with a compact flame. Nonlinear effects are accounted for by employing the flame describing function (FDF). An integral governing equation for the acoustic velocity at the flame is derived. This is solved by an iteration method to obtain the time history of the acoustic velocity at the flame. The coupling mechanism, which is nonlinear due to the amplitude-dependence of the FDF, is explored using a two-mode analysis as an illustrative example. Different scenarios are observed when the initial amplitude is varied: the long-term behaviour of the time history may be dominated by one of the modes, which forms a limit cycle and squeezes out the other mode, i.e. there is a mutually inhibitory effect; however, it is also possible, for both modes to coexist. This dependence on the initial condition is a consequence of the amplitude-dependent heat release rate, and it is clearly a nonlinear effect. The time history calculation is supplemented by a phase analysis, which is based on the Rayleigh criterion and reveals the stability behaviour and limit cycles of the individual modes. In order to simulate changing operating conditions in a real afterburner, the coupling coefficient and the time-lag in the heat release rate are changed abruptly during the time history calculation. The change in coupling coefficient has no dramatic effect, while the change in time-lag can lead to mode switch. This is examined in detail by the phase analysis, which reveals that mode switch is also a nonlinear effect.

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引用次数: 0

Defect quantification evaluation of a rolling element bearing based on physical modelling and instantaneous vibration energy investigation

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-12-03 DOI: 10.1016/j.jsv.2024.118875

Maolin Luo , Yu Guo , Zuqiang Su , Hugo André , Zhi Tang , Chen Zhou , Chao Li

The estimation of defect size of rolling element bearing (REB) is expected to remain a significant and challenging task in vibration-based condition monitoring of rotating machinery. The conventional approaches focus on extracting the time spacing of the double impulse signal to estimate the defect size of the REB which is subsequently found to be inaccurate and arbitrary. In this paper, a novel model is developed to estimate the defect size of the REB based on the theories of physics and kinematics, in which the multi-event excitations, i.e. the entry, destressing and collision generated by the rolling element-defect interaction, are considered and investigated. The kinematic and geometric contact mechanism, which is mapped onto the rolling element-defect interaction as the rolling element passes over the defect zone, are analysed and modelled as a function of the time information. In view of the fact that the variation of the vibration energy contained in the multi-impact vibration response is deeply mapped to the time information, a novel idea is proposed to extract the time information by analysing the instantaneous energy variation of the defect-induced impulse using the scheme of the autoregressive model and the smooth pseudo Wigner–Ville distribution. The proposed model and idea are validated by experiments under different defect size and rotational speed scenarios. The results calculated by the proposed model show good agreement with the real defect size. Experimental and modelling comparisons show that the proposed model has reliable effectiveness and good performance and confidence in quantifying the size of the defect area localized on the outer raceway of the REB, and can provide some theoretical guidance for damage detection and remaining useful life prediction of the REB.

{"title":"Defect quantification evaluation of a rolling element bearing based on physical modelling and instantaneous vibration energy investigation","authors":"Maolin Luo , Yu Guo , Zuqiang Su , Hugo André , Zhi Tang , Chen Zhou , Chao Li","doi":"10.1016/j.jsv.2024.118875","DOIUrl":"10.1016/j.jsv.2024.118875","url":null,"abstract":"<div><div>The estimation of defect size of rolling element bearing (REB) is expected to remain a significant and challenging task in vibration-based condition monitoring of rotating machinery. The conventional approaches focus on extracting the time spacing of the double impulse signal to estimate the defect size of the REB which is subsequently found to be inaccurate and arbitrary. In this paper, a novel model is developed to estimate the defect size of the REB based on the theories of physics and kinematics, in which the multi-event excitations, i.e. the entry, destressing and collision generated by the rolling element-defect interaction, are considered and investigated. The kinematic and geometric contact mechanism, which is mapped onto the rolling element-defect interaction as the rolling element passes over the defect zone, are analysed and modelled as a function of the time information. In view of the fact that the variation of the vibration energy contained in the multi-impact vibration response is deeply mapped to the time information, a novel idea is proposed to extract the time information by analysing the instantaneous energy variation of the defect-induced impulse using the scheme of the autoregressive model and the smooth pseudo Wigner–Ville distribution. The proposed model and idea are validated by experiments under different defect size and rotational speed scenarios. The results calculated by the proposed model show good agreement with the real defect size. Experimental and modelling comparisons show that the proposed model has reliable effectiveness and good performance and confidence in quantifying the size of the defect area localized on the outer raceway of the REB, and can provide some theoretical guidance for damage detection and remaining useful life prediction of the REB.</div></div>","PeriodicalId":17233,"journal":{"name":"Journal of Sound and Vibration","volume":"600 ","pages":"Article 118875"},"PeriodicalIF":4.3,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143177359","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

Acoustic-modeling of random fibrous materials

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-12-03 DOI: 10.1016/j.jsv.2024.118897

Xiangjun Peng , Yuxuan Huang , Chenlei Yu , Xiangyu Xie , Wei He , Tian Jian Lu

We present a microstructure-based model for determining the sound absorption behavior and transport parameters of random fibrous materials and exploring the physical mechanisms underlying acoustic energy dissipation. In order to increase the generalizability of the model, a three-dimensional random fiber structure is employed for simulation. The propagation of sound waves is associated with four transport parameters, including viscous permeability, tortuosity, as well as viscous and thermal characteristic lengths. These parameters are determined by the porosity and diameter of the fibrous material. By using the method of multi-scale asymptotic simulation, the theoretical model for transport parameters includes unknown coefficients that are adjusted based on the simulated results. The sound absorption coefficients are then obtained by integrating the transport parameters into the widely-used Johnson-Champoux-Allard (JCA) model for porous materials. The theoretical predictions match well with existing experimental measurements on sintered fiber metals and fibrous copper wires. Our model systematically examines the impact of fiber diameter, porosity, and material thickness on sound absorption performance. Optimal results are achieved by carefully selecting fiber diameter and porosity to enhance the acoustic dissipation of sound waves, while thicker fibrous materials increase sound absorption in the low frequency range. The model provides a theoretical framework for designing and fabricating fibrous materials to reduce noise.

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引用次数: 0

Self-sensing sliding mode control of workpiece chatter based on accurate prediction of machining vibration

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-12-01 DOI: 10.1016/j.jsv.2024.118887

Zhenmin Li , Qinghua Song , Jixiang Gong , Xinyu Yang , Jing Qin , Haifeng Ma , Zhanqiang Liu

The previous works concerning active chatter suppression in milling systems are generally carried out based on specially designed tool holders or spindles. Due to the continuous removal of materials, however, the workpiece system cannot be treated as quasi-static or rigid. In this paper, a manufacturing system based on the digital twins (DT) model and sliding mode (SM) controller is developed to suppress the milling chatter of thin-walled workpieces. A single degree of freedom (DOF) model of the workpiece is adopted to describe the milling system. The developed SM algorithm exhibits a good performance under the variations of modal parameters, cutting parameters, unmodeled dynamics, etc. To provide accurate control feedback, a DT model of workpiece vibration is established by presenting a self-sensing predictive method. The predictive methods are implemented based on the cooperation of the combination methods of beam functions (CMOBF) and the mode superposition method (MSM). In addition, the predictive accuracy is discussed quantitatively by establishing a dataset of error coefficients. The data of error coefficients are trained by the support vector machine (SVM) model, which is introduced to the predictive methods for further error modification. Finally, a DT framework is introduced briefly to combine the machining system and the control process. Based on the developed DT-driven manufacturing system, the information interaction between the control process and the vibrating system can be realized.

{"title":"Self-sensing sliding mode control of workpiece chatter based on accurate prediction of machining vibration","authors":"Zhenmin Li , Qinghua Song , Jixiang Gong , Xinyu Yang , Jing Qin , Haifeng Ma , Zhanqiang Liu","doi":"10.1016/j.jsv.2024.118887","DOIUrl":"10.1016/j.jsv.2024.118887","url":null,"abstract":"<div><div>The previous works concerning active chatter suppression in milling systems are generally carried out based on specially designed tool holders or spindles. Due to the continuous removal of materials, however, the workpiece system cannot be treated as quasi-static or rigid. In this paper, a manufacturing system based on the digital twins (DT) model and sliding mode (SM) controller is developed to suppress the milling chatter of thin-walled workpieces. A single degree of freedom (DOF) model of the workpiece is adopted to describe the milling system. The developed SM algorithm exhibits a good performance under the variations of modal parameters, cutting parameters, unmodeled dynamics, etc. To provide accurate control feedback, a DT model of workpiece vibration is established by presenting a self-sensing predictive method. The predictive methods are implemented based on the cooperation of the combination methods of beam functions (CMOBF) and the mode superposition method (MSM). In addition, the predictive accuracy is discussed quantitatively by establishing a dataset of error coefficients. The data of error coefficients are trained by the support vector machine (SVM) model, which is introduced to the predictive methods for further error modification. Finally, a DT framework is introduced briefly to combine the machining system and the control process. Based on the developed DT-driven manufacturing system, the information interaction between the control process and the vibrating system can be realized.</div></div>","PeriodicalId":17233,"journal":{"name":"Journal of Sound and Vibration","volume":"600 ","pages":"Article 118887"},"PeriodicalIF":4.3,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143175469","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

Stability and dynamic response of centrifugal pendulum vibration absorber based on nonlinear hybrid damping

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-30 DOI: 10.1016/j.jsv.2024.118869

Yizhe Zhang , Yi Zhang , Massimiliano Gobbi , Guangqiang Wu

Centrifugal pendulum vibration absorber (CPVA) have emerged as an extremely effective method to mitigate torsional vibrations in rotating machinery. Previous studies have predominantly focused on viscous damping between pendulums and rotor, largely ignoring other damping mechanisms. However, recent experimental endeavors have revealed a hybrid damping concept that combines rolling and viscous damping, providing a more realistic portrayal of CPVA dynamics in vehicular applications. This study builds on prior investigations by incorporating nonlinear hybrid damping of the pendulums and investigating the steady-state and transient behavior of the CPVA within gravitational and centrifugal force fields. We propose a methodology for deriving pendulum equations of motion based on perturbation and multiple scales. Subsequently, we investigated the CPVA’s critical stability and bifurcation as well as a variety of nonlinear phenomena, using numerical simulations to validate our results. Furthermore, our study revealed a novel phenomenon known as the ‘phase jump’ for the pendulum. It is worth noting that the CPVA’s dynamic performance can be improved and the local nonlinear response can be reduced by adjusting the share and magnitude of the rolling and viscous damping coefficients. This study provides insights for optimizing the CPVA’s performance and advancing its efficacy.

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引用次数: 0

Target-free vision method for planar displacement measurement of structures subjected to out-of-plane movement by UAV

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-30 DOI: 10.1016/j.jsv.2024.118873

Dong Tan , Jun Li , Hong Hao

In the field of structural health monitoring, one of the essential tasks is to measure dynamic responses such as vibration displacement. With the recent advancement in computer vision, cameras are developed as alternative tools to traditional displacement sensors. Unmanned aerial vehicles (UAVs) offer mobility and can handle complex real-world situations. However, limitations of using UAVs, particularly self-motions, have hindered the accuracy in vibration displacement measurements. This paper proposes a target-free vision-based approach for measuring dynamic displacement responses using UAV. A series of videos of a beam subjected to planar motions are captured using a UAV. Stationary features on the background and target features on the structure are detected using features from accelerated segment test with adaptive threshold strategy and tracked using the Kanade–Lucas–Tomasi. UAV self-motions are estimated using motion-only bundle adjustment. Dynamic displacement responses of the structure are computed based on the displacements of target features and UAV self-motions. Results of the displacement responses and identified natural frequencies with different planar motion types and shooting angles are obtained. They are compared with those obtained by linear variable differential transducers, which demonstrates the accuracy of the proposed method for vibration displacement response measurement.

{"title":"Target-free vision method for planar displacement measurement of structures subjected to out-of-plane movement by UAV","authors":"Dong Tan , Jun Li , Hong Hao","doi":"10.1016/j.jsv.2024.118873","DOIUrl":"10.1016/j.jsv.2024.118873","url":null,"abstract":"<div><div>In the field of structural health monitoring, one of the essential tasks is to measure dynamic responses such as vibration displacement. With the recent advancement in computer vision, cameras are developed as alternative tools to traditional displacement sensors. Unmanned aerial vehicles (UAVs) offer mobility and can handle complex real-world situations. However, limitations of using UAVs, particularly self-motions, have hindered the accuracy in vibration displacement measurements. This paper proposes a target-free vision-based approach for measuring dynamic displacement responses using UAV. A series of videos of a beam subjected to planar motions are captured using a UAV. Stationary features on the background and target features on the structure are detected using features from accelerated segment test with adaptive threshold strategy and tracked using the Kanade–Lucas–Tomasi. UAV self-motions are estimated using motion-only bundle adjustment. Dynamic displacement responses of the structure are computed based on the displacements of target features and UAV self-motions. Results of the displacement responses and identified natural frequencies with different planar motion types and shooting angles are obtained. They are compared with those obtained by linear variable differential transducers, which demonstrates the accuracy of the proposed method for vibration displacement response measurement.</div></div>","PeriodicalId":17233,"journal":{"name":"Journal of Sound and Vibration","volume":"600 ","pages":"Article 118873"},"PeriodicalIF":4.3,"publicationDate":"2024-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143177353","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

Investigation on the dominant mechanism of chatter in high-load robot milling process based on theoretical and experimental analysis

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-29 DOI: 10.1016/j.jsv.2024.118886

Yuchao Du , Zhiqiang Liang , Zirui Gao , Sichen Chen , Yi Yue , Jiabo Zhang , Hanliang Liu , Haoran Zheng , Baolong Liu , Tianyang Qiu , Zhibing Liu

Chatter has always been a key problem restricting the improvement of robotic milling quality and efficiency. To avoid chatter, it is necessary to determine what is the dominant chatter mechanism (mode coupling or regenerative) of the robot milling system. Therefore, this paper focus on the dominant chatter mechanism in high-load (600kg) robot milling. The modal test results show that the dynamic flexibility of spindle-tool structure mode in high-load robot is significantly higher than that of the body structure mode, which is significantly different from the low-load robot in other studies. The mode coupling chatter stability prediction models are established based on eigenvalue method and zeroth order approximation, and the predicted stability boundaries are compared with the experimental results. The results show that only high-frequency chatter exists in the high speed region (1000–8000rpm), and no low frequency chatter occurs. The low-frequency chatter around the robot body mode is found in the low-speed region (400–1000rpm), but the mode coupling chatter theory could not explain the chatter varies periodically with the spindle speed. However, the stability boundary predicted by the regenerative chatter theory also changes periodically with the spindle speed. This indicates that the milling chatter dominant mechanism of high load robot is regenerative chatter. This study analyzes the milling chatter dominant mechanism of high-load robot through theoretical and experimental verification, which can provide theoretical support for high-load robot milling chatter control.

{"title":"Investigation on the dominant mechanism of chatter in high-load robot milling process based on theoretical and experimental analysis","authors":"Yuchao Du , Zhiqiang Liang , Zirui Gao , Sichen Chen , Yi Yue , Jiabo Zhang , Hanliang Liu , Haoran Zheng , Baolong Liu , Tianyang Qiu , Zhibing Liu","doi":"10.1016/j.jsv.2024.118886","DOIUrl":"10.1016/j.jsv.2024.118886","url":null,"abstract":"<div><div>Chatter has always been a key problem restricting the improvement of robotic milling quality and efficiency. To avoid chatter, it is necessary to determine what is the dominant chatter mechanism (mode coupling or regenerative) of the robot milling system. Therefore, this paper focus on the dominant chatter mechanism in high-load (600kg) robot milling. The modal test results show that the dynamic flexibility of spindle-tool structure mode in high-load robot is significantly higher than that of the body structure mode, which is significantly different from the low-load robot in other studies. The mode coupling chatter stability prediction models are established based on eigenvalue method and zeroth order approximation, and the predicted stability boundaries are compared with the experimental results. The results show that only high-frequency chatter exists in the high speed region (1000–8000rpm), and no low frequency chatter occurs. The low-frequency chatter around the robot body mode is found in the low-speed region (400–1000rpm), but the mode coupling chatter theory could not explain the chatter varies periodically with the spindle speed. However, the stability boundary predicted by the regenerative chatter theory also changes periodically with the spindle speed. This indicates that the milling chatter dominant mechanism of high load robot is regenerative chatter. This study analyzes the milling chatter dominant mechanism of high-load robot through theoretical and experimental verification, which can provide theoretical support for high-load robot milling chatter control.</div></div>","PeriodicalId":17233,"journal":{"name":"Journal of Sound and Vibration","volume":"600 ","pages":"Article 118886"},"PeriodicalIF":4.3,"publicationDate":"2024-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143175949","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

Concave-shaped acoustic black holes with asymmetric arrangement for suppression and amplification of structural vibration

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-29 DOI: 10.1016/j.jsv.2024.118885

Seongmin Park, Wonju Jeon

An acoustic black hole (ABH) is a wedge-shaped structure characterized by a power-law thickness profile with an exponent greater than or equal to two. In this study, we engineer an ABH with a concave shape, where both the width and thickness decrease according to power-law profiles. This configuration facilitates the focusing of elastic waves at the tip region with higher energy density than conventional constant-width ABHs. The highly focused waves are attenuated using a small amount of viscoelastic material attached near the tip of the ABH, resulting in dampened vibrations in the original structure such as a thin beam. Despite being about half the weight of the conventional ABH of equivalent length, the concave ABH achieves similar damping performance to the conventional one. When the conventional ABH is adjusted to match the weight of our concave design, the latter exhibits enhanced damping performance along with a lower cut-on frequency. Near-perfect reduction of structural vibration is attained by affixing a concave ABH to each end of the beam. By delicately adjusting their lengths and employing them asymmetrically, we manipulate the vibration mode shapes to minimize the structural vibrations. As a result, vibrations in the beam are barely perceptible under high-frequency harmonic excitation. The concave ABH, characterized by its ability to intensively focus elastic waves at its narrow and thin tip, is also suitable for vibration amplification, facilitating the detection of minute vibrations distributed in the original structure. The concave ABH offers improved performance in both wave absorption and amplification compared with conventional ABHs of the same length or weight, highlighting its potential as an alternative solution in vibration damping or sensing applications.

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引用次数: 0

Multi-scale analysis of the mapping relationship between turnout irregularities and vehicle responses based on cross-wavelet transform

IF 4.3 2区工程技术 Q1 ACOUSTICS

Journal of Sound and Vibration

Pub Date : 2024-11-29 DOI: 10.1016/j.jsv.2024.118884

Xueyang Tang , Xiaopei Cai , Yuqi Wang , Fei Yang

Track irregularities significantly impact the dynamic performance of vehicles passing through turnouts. Despite this, the precise mapping relationship between these irregularities and vehicle responses remains unclear. Utilizing measured data, the inherent irregularities of turnouts were extracted using improved complete ensemble empirical mode decomposition with adaptive noise (ICEEMDAN). The mapping relationship between the wavelength, spatial position, and time lag effect of turnout inherent irregularities and vehicle responses was analyzed using cross-wavelet transform (CWT). The first-order and second-order intrinsic modal components within the original irregularities distinctly reflect the inherent characteristics of the switch and crossing panels. The inherent irregularities in these panels respectively correspond to the vertical and lateral accelerations of the vehicle within the wavelength ranges of 2∼4 m and 4∼8 m. Within the switch panel, the longitudinal levels of the right rail and the twist exert the most significant influence on the vehicle's vertical acceleration, accounting for 17.80 % and 22.89 % respectively. In the crossing panel, the track gauge and the alignments of the right rail have the greatest impact on the vehicle's lateral acceleration, accounting for 24.72 % and 35.18 % respectively.

{"title":"Multi-scale analysis of the mapping relationship between turnout irregularities and vehicle responses based on cross-wavelet transform","authors":"Xueyang Tang , Xiaopei Cai , Yuqi Wang , Fei Yang","doi":"10.1016/j.jsv.2024.118884","DOIUrl":"10.1016/j.jsv.2024.118884","url":null,"abstract":"<div><div>Track irregularities significantly impact the dynamic performance of vehicles passing through turnouts. Despite this, the precise mapping relationship between these irregularities and vehicle responses remains unclear. Utilizing measured data, the inherent irregularities of turnouts were extracted using improved complete ensemble empirical mode decomposition with adaptive noise (ICEEMDAN). The mapping relationship between the wavelength, spatial position, and time lag effect of turnout inherent irregularities and vehicle responses was analyzed using cross-wavelet transform (CWT). The first-order and second-order intrinsic modal components within the original irregularities distinctly reflect the inherent characteristics of the switch and crossing panels. The inherent irregularities in these panels respectively correspond to the vertical and lateral accelerations of the vehicle within the wavelength ranges of 2∼4 m and 4∼8 m. Within the switch panel, the longitudinal levels of the right rail and the twist exert the most significant influence on the vehicle's vertical acceleration, accounting for 17.80 % and 22.89 % respectively. In the crossing panel, the track gauge and the alignments of the right rail have the greatest impact on the vehicle's lateral acceleration, accounting for 24.72 % and 35.18 % respectively.</div></div>","PeriodicalId":17233,"journal":{"name":"Journal of Sound and Vibration","volume":"600 ","pages":"Article 118884"},"PeriodicalIF":4.3,"publicationDate":"2024-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143177354","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