Article
Automation & Control Systems
Yusheng Niu, Xiuqing Hao, Annan Xia, Li Wang, Qiankai Liu, Liang Li, Ning He
Summary: Hydrodynamic bearing is essential for high-accuracy devices like high-speed machine tools, and partially textured bearings have shown outstanding anti-vibration performance. Research findings indicate that partially textured bearings with a 60% texture ratio and 4.9% area ratio exhibit the best properties, significantly reducing vibration amplitudes and improving static and dynamic stiffness.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2022)
Article
Engineering, Mechanical
Zi Wang, Caichao Zhu
Summary: Due to the changing number of rolling elements in the load zone, rolling element bearings exhibit load-dependence and varying-compliance with the cage rotation. A bearing enhanced excitation force model is developed to capture the non-linear varying compliance excitation in the gear transmission system, considering various dynamic excitations. An advanced iterative numerical method is introduced to accurately update the excitations caused by load-dependent and time-varying nonlinearities inside the system. The effects of bearing load-dependence and varying compliance on the system's nonlinear vibration behaviors are investigated.
NONLINEAR DYNAMICS
(2023)
Article
Mathematics, Applied
Zhongliang Xie, Kang Yang, Jian Jiao, Weiyang Qin, Tao Yang, Chao Fu, Anbo Ming
Summary: This paper clarifies the mechanism of the dynamic characteristics of the water-lubricated bearing-rotor coupling system at different operating stages. Dynamic models of the system are developed to investigate the influences of different operating modules on the dynamic characteristics. The effects of different speeds, different loads, and different impacts are analyzed. Experimental results verify the validity of the newly developed models, providing theoretical foundations for the optimum design of such bearing-rotor systems.
Article
Engineering, Mechanical
Bin Fang, Shaoke Wan, Jinhua Zhang, Jun Hong
Summary: This article studies the stiffness fluctuation behaviors of ball bearings under different operating conditions, proposing an improved mathematical model with wider applicability. Results show that increasing axial load can effectively reduce stiffness fluctuation amplitudes and frequency components.
JOURNAL OF MECHANICAL DESIGN
(2021)
Article
Engineering, Mechanical
Yanyan Nie, Liming Wang, Fangyi Li, Jianfeng Li, Peng Cui, Jiaqi Hu, Guoyan Li, Yanle Li
Summary: This paper proposes a model-based vibration signal analysis method to interpret and understand the vibration characteristics of planetary gearboxes (PGs), providing guidance for their condition monitoring and fault diagnosis. By constructing a mathematical model of transmission path effects and a phenomenological vibration model, a comprehensive vibration signal model that accurately simulates the dynamic response of PGs is established. The vibration characteristics of the obtained signals are analyzed and validated through experiments and simulations.
MECHANISM AND MACHINE THEORY
(2022)
Article
Engineering, Mechanical
Yanyan Nie, Fangyi Li, Liming Wang, Jianfeng Li, Mengyao Wang, Mingshuai Sun, Guoyan Li, Yanle Li
Summary: Planetary gearboxes are prone to gear local faults due to their difficult working environment, which can lead to significant losses and catastrophic events. This study proposes an improved phenomenological vibration model and calculates the relative phases between gear pairs to establish vibration models with/without local faults in order to diagnose these faults. Spectral structures and LFCFs are derived for diagnosis purposes, and simulation and experimental studies demonstrate the effectiveness of the proposed models.
MECHANISM AND MACHINE THEORY
(2022)
Article
Engineering, Mechanical
Daniel Fritz Ploger, Christian Fischer, Stephan Rinderknecht
Summary: Through experimental and numerical studies, the modulation of gear mesh vibration in small planetary gearboxes is examined, revealing a correlation between vibration modulation and deviations from ideal geometry during manufacturing and assembly, as well as significant influence from operating conditions.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2021)
Article
Acoustics
Mian Zhang, Decai Li, Ming J. Zuo, Jun Liu, Hongbiao Xiang, Yang Song, Kesheng Wang
Summary: This paper discusses the modeling of vibration characteristics of planetary gearboxes, points out some issues in previous research, and proposes an improved method. By mapping the phase variation of multiple-planet gears into time-varying propagating distance, the neutralization phenomena of frequency components are solved, and a more reasonable model is proposed.
JOURNAL OF SOUND AND VIBRATION
(2021)
Article
Engineering, Mechanical
Xinghua Zhou, Dingxuan Zhao, Xiao Sun, Xiao Yang, Jianhai Zhang, Tao Ni, Kehong Tang
Summary: A novel passive asymmetric quasi-zero stiffness vibration isolator (AQZS-VI) using a combination-built negative stiffness element (NSE) is proposed. The nonlinear stiffness and damping properties of the AQZS-VI are studied, and experimental results confirm its superior vibration isolation performance.
NONLINEAR DYNAMICS
(2022)
Article
Mechanics
Tiancheng Gao, Xianfeng Wang, Chen Liu, Jun Xiao, Cong Zhao
Summary: The vibration characteristics of composite laminated plates with variable stiffness were studied using modal analysis and free vibration attenuation experiments. Twenty-five variable stiffness laminates were tested by varying parameters such as fiber angle, curve ply ratio, and number of layers. The results showed that these parameters had a significant impact on the modal frequency and damping of the laminates. This study can serve as a reference for future research due to the limited experimental investigations on the vibration characteristics of variable stiffness composite laminates.
COMPOSITE STRUCTURES
(2023)
Article
Engineering, Mechanical
Bin Fang, Ke Yan, Jun Hong, Jinhua Zhang
Summary: This paper presents the details of the composition form and classification method of the elements in bearing stiffness matrix, and reveals the effects of the off-diagonal stiffness items on the rotor dynamic characteristics. The results show that, additional loads from ball bearings are generated due to the off-diagonal stiffness elements in bearing stiffness matrix when the rotor system is subjected to a radial load or moment load.
MECHANISM AND MACHINE THEORY
(2021)
Article
Geochemistry & Geophysics
J. A. Priest, M. Abbas, J. L. Hayley
Summary: Laboratory tests on gas-saturated hydrate-bearing sand specimens showed that the formation of hydrate led to significant increases in stiffness and strength of the sand. Water saturation subsequently resulted in a reduction of around 90% in stiffness and 70% in strength. The changes in behavior were attributed to the dissociation and dissolution of the hydrate, with remaining hydrate acting as more of a pore filler.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Engineering, Mechanical
Di Yang, Xi Wang
Summary: This study proposed a method based on the singular value decomposition of block matrices in the stiffness matrix to analyze the mapping structure of bearing stiffness matrix. By calculating and analyzing the time-varying stiffness matrix of double-row tapered bearing using this method, the stiffness properties and vibration transmission properties of the bearing are revealed.
ACTA MECHANICA SINICA
(2022)
Article
Acoustics
Vasiliy Migal, Shchasiana Arhun, Mykhailo Shuliak, Andrii Hnatov, Iryna Trunova, Igor Shevchenko
Summary: This paper discusses the development of a vibration-based technique for evaluating the quality and detecting design and manufacturing defects of tractor gearboxes. The study includes experimental research on the vibro-diagnostic characteristics of tractor gearboxes, vibration measurement and spectrum analysis, determination of statistical limit values of vibration parameters, and comparison of vibration characteristics with acceptable vibrations. It has been found that the vibration levels of gearboxes during manufacturing exceed the acceptable vibrations, leading to accelerated faults and reduced lifetime. The results have practical significance in improving the design and manufacturing of tractor gearboxes and enhancing the reliability of tractors.
JOURNAL OF VIBRATION AND CONTROL
(2023)
Article
Acoustics
Hao Wang, Jie Liu, Weiqiang Zhao
Summary: In this paper, a dynamics model of the gear-bearing transmission system with bending and torsion coupling is established, taking into account the influence of gear shifting on the vibration characteristics. The time-varying mesh stiffness of the profile shifted gear is derived using the potential energy method. The vibration differential equation is obtained using the Lagrange equation numerical method and solved using the fourth-order Runge-Kutta method. The influence of the profile shifted coefficient and input torque on the vibration characteristics of the gear transmission system is analyzed using time and frequency domain graphs.
JOURNAL OF LOW FREQUENCY NOISE VIBRATION AND ACTIVE CONTROL
(2023)
Article
Acoustics
Sandip Chajjed, Mohammad Khalil, Dominique Poirel, Chris Pettit, Abhijit Sarkar
Summary: This paper reports the generalization of the Bayesian formulation of the flutter margin method, which improves the predictive performance by incorporating the joint prior of aeroelastic modal parameters. The improved algorithm reduces uncertainties in predicting flutter speed and can cut cost by reducing the number of flight tests.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Pascal Zeise, Bernhard Schweizer
Summary: Air ring bearings are an improved version of classical air bearings, providing better damping behavior and allowing operation above the linear threshold speed of instability. However, there is a risk of dangerous vibrations in certain rotor systems, which can be addressed by considering ring tilting effects.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Zbynek Sika, Jan Krivosej, Tomas Vyhlidal
Summary: This paper presents a novel design of a compact six degrees of freedom active vibration absorber with six identical eigenfrequencies. The objective is to completely suppress the vibration of a machine structure with six motion components. By utilizing a Stewart platform structure equipped with six active legs, a spatial unifrequency absorber with six identical eigenfrequencies is achieved. The design is optimized using a correction feedback and active delayed resonator feedback.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Kai Li, Yufeng Liu, Yuntong Dai, Yong Yu
Summary: This paper presents a novel light-powered self-oscillating liquid crystal elastomer (LCE) bow that can self-oscillate continuously and periodically under steady illumination. The dynamics of the LCE bow are theoretically investigated and numerical calculations predict its motion regimes. The suggested LCE bow offers potential advantages in terms of simple structure, customizable size, flexible regulation, and easy assembly.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Carmelo Rosario Vindigni, Giuseppe Mantegna, Calogero Orlando, Andrea Alaimo
Summary: In this study, a simple adaptive flutter suppression system is designed to increase the operative speed range of a wing-aileron aeroelastic plant. The system achieves almost strictly passivity by using a parallel feed-forward compensator implementation and the controller parameters are optimized using a population decline swarm optimization algorithm. Numerical simulations prove the effectiveness of the proposed simple adaptive flutter suppression architecture in different flight scenarios.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Nicco Ulbricht, Alain Boldini, Peng Zhang, Maurizio Porfiri
Summary: The quantification of fluid-structure interactions in marine structures is crucial for their design and optimization. In this study, an analytical solution for the free vibration of a bidirectional composite in contact with a fluid is proposed. By imposing continuity conditions and boundary conditions, the coupled fluid-structure problem is solved and applied to sandwich structures in naval construction, offering insights into the effects of water on mode shapes and through-the-thickness profiles of displacement and stress.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Shahram Hadian Jazi, Mostafa Hadian, Keivan Torabi
Summary: Non-uniformity and damage are the main focus in studying vibrations of beam elements. An exact closed-form explicit solution for the transverse displacement of a nonuniform multi-cracked beam is introduced using generalized functions and distributional derivative concepts. By introducing non-dimensional parameters, the motion equation and its closed-form solution are obtained based on four fundamental functions. The impact of crack count, location, intensity, and boundary conditions on natural frequency and mode shape is evaluated through numerical study.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Eugenio Tramacere, Marius Pakstys, Renato Galluzzi, Nicola Amati, Andrea Tonoli, Torbjoern A. Lembke
Summary: This paper proposes the experimental stabilization of electrodynamic maglev systems by means of passive components, providing key technological support for the Hyperloop concept of high-speed and sustainable transportation.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Pengfei Deng, Xing Tan, He Li
Summary: In this paper, the authors improve the surface morphology method and study the bit-rock interaction model between the rock and the PDC bit, taking into account the impact of blade shape and cutter arrangement. They establish a dynamic model for a deep drilling system equipped with an arbitrary shape PDC bit and propose a stability prediction method. The results show that the shape of the blades and arrangement of the cutters on the PDC bit significantly affect the nonlinear vibration of the drilling system.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Salvador Rodriguez-Blanco, Javier Gonzalez-Monge, Carlos Martel
Summary: In modern LPT designs, the simultaneous presence of forced response and flutter in different operation regimes is unavoidable. Recent evidence suggests that the traditional linear superposition method may be overly conservative. This study examines the flutter and forced response interaction in a realistic low pressure turbine rotor and confirms that the actual response is much smaller than that predicted by linear superposition.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Kabilan Baskaran, Nur Syafiqah Jamaluddin, Alper Celik, Djamel Rezgui, Mahdi Azarpeyvand
Summary: This study investigates the impact of the number of blades on the aeroacoustic characteristics and aerodynamic performance of propellers used in urban air mobility vehicles. The results show that different blade numbers exhibit distinct noise levels, providing valuable insights for further research on propeller noise and aerodynamic performance.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Yongbo Peng, Peifang Sun
Summary: This study focuses on the reliability-based design optimization (RBDO) of the tuned mass-damper-inerter (TMDI) system under non-stationary excitations. The performance of the optimized TMDI system is evaluated using probability density evolution analysis. The results demonstrate the technical advantages of TMDI, including high vibration mitigation performance, considerable mass reduction, and less stroke demand.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Guanfu Lin, Zhong-Rong Lu, Jike Liu, Li Wang
Summary: Vision-based measurement is an emerging method that enables full-field measurement with non-contact and high spatial resolution capabilities. This paper presents a single-camera method for measuring out-of-plane vibration of plate structures using motion-parametric homography to capture image variation and displacement response.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Bronislaw Czaplewski, Mateusz Bocian, John H. G. Macdonald
Summary: Despite two decades of study, there is currently no model that can quantitatively explain pedestrian-generated lateral forces. This research proposes a foot placement control law based on empirical data to calibrate and generalize the rigid-leg inverted pendulum model (IPM) for predicting lateral structural stability.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Justine Carpentier, Jean-Hugh Thomas, Charles Pezerat
Summary: This paper proposes an improved method for the identification of vibration sources on a car window using the corrected force analysis technique. By redefining inverse methods in polar coordinates, more accurate results can be obtained.
JOURNAL OF SOUND AND VIBRATION
(2024)