Article
Engineering, Marine
Xiling Xie, Dequan Yang, Mingke Ren, Zhiyi Zhang
Summary: An active/passive support method is proposed to suppress the transmission of vibration from a flexible shaft-bearing system to its foundation. The combination of passive isolators and electromagnetic suspension is used to achieve effective vibration suppression. Based on the developed dynamic model, the adjustment of stiffness, the transmissibility of vibration, and the effectiveness of active control are analyzed. The results demonstrate that the active/passive support method can significantly reduce vibration transmission and effectively mitigate foundation vibration.
Article
Engineering, Civil
Liangkun Wang, Satish Nagarajaiah, Ying Zhou, Weixing Shi
Summary: In this study, an adaptive-passive variable stiffness tuned mass damper (APVS-TMD) is proposed to solve the mistuning problem of a passive TMD. The stiffness and frequency of the APVS-TMD can be retuned by changing the length of the cantilever beam and adjusting the air gap between the conductor plate and magnets. Numerical simulation and experimental verification show that the APVS-TMD can accurately identify the decoupled structural natural frequency and effectively control human-induced vibrations.
ENGINEERING STRUCTURES
(2023)
Article
Chemistry, Multidisciplinary
Mohamed Habib Farhat, Xavier Chiementin, Fakher Chaari, Fabrice Bolaers, Mohamed Haddar
Summary: This research aims to automate the process of identifying bearing defects under variable operating speeds by utilizing updated frequency domain features based on order analysis technique. The proposed features effectively identify a variety of bearing defects under different operating speeds through the construction of a predictive multi-kernel support vector machine classification model.
APPLIED SCIENCES-BASEL
(2021)
Article
Acoustics
Guoqing Jiang, Yu Wang, Fengming Li, Xingjian Jing
Summary: A novel integrated nonlinear passive vibration control system is proposed, combining a bio-inspired isolator and a non-linear energy sink, which can achieve excellent vibration isolation and reduce resonance amplitude in low-frequency bands. Experimental validation of the superior vibration reduction properties of the system was conducted, and the design methodology was elaborated for practical applications, providing an innovative method for vibration control in various engineering practices.
JOURNAL OF SOUND AND VIBRATION
(2021)
Article
Engineering, Mechanical
Eduardo Afonso Ribeiro, Diogo Stuani Alves, Katia Lucchesi Cavalca, Carlos Alberto Bavastri
Summary: This study proposes a mathematical model that combines analytical calculation of oil-film coefficients, fractional derivative approach for the viscoelastic materials dynamics, and generalized equivalent parameters for dynamically modeling hybrid oil-bearing-viscoelastic-support systems. Through simulations, it is shown that viscoelastic supports improve the stability of rotating systems, and optimization can enhance vibration suppression characteristics of the device.
MECHANISM AND MACHINE THEORY
(2021)
Article
Robotics
Emma Treadway, R. Brent Gillespie
Summary: Passive transmission-based robotic devices provide motion guidance while ensuring user safety and engagement. Discretely variable devices based on brakes and hydrostatic transmissions offer advantages over continuously variable transmissions.
IEEE TRANSACTIONS ON ROBOTICS
(2021)
Article
Thermodynamics
Haishan Cao
Summary: This study introduces the vibration issues and measurement methods of cryocoolers, discusses the basic concept of vibration isolation, as well as the progress in passive and active vibration isolation.
Article
Acoustics
Yanwei Xu, Weiwei Cai, Tancheng Xie
Summary: This study proposed a rolling bearing fault diagnosis method based on information fusion, which can accurately identify the fault type of the subway traction motor bearing by establishing a test and multi-information acquisition system and using convolution neural network to fuse feature information. Experimental results show that the accuracy can reach 100% when the neural network training set and test set cover the same working conditions.
SHOCK AND VIBRATION
(2021)
Review
Engineering, Aerospace
Zepeng He, Xiangchao Feng, Yeqing Zhu, Zhibo Yu, Zhen Li, Yan Zhang, Yinhang Wang, Pengfei Wang, Liangyu Zhao
Summary: This study investigates the current state of Stewart vibration isolation platforms in the field of aerospace micro-vibration, summarizes the characteristics and advantages and disadvantages of four vibration isolation technologies. It also introduces the development process of the Stewart vibration isolation platform and the research on kinematics, dynamics, and braking control algorithms. Additionally, the idea of fabricating the Stewart platform using 4D printing technology is proposed.
Article
Chemistry, Multidisciplinary
Edgar F. Sierra-Alonso, Julian Caicedo-Acosta, Alvaro Angel Orozco Gutierrez, Hector F. Quintero, German Castellanos-Dominguez
Summary: This study introduces an approach to detect incipient failures of rotating machinery's bearings through time-frequency methods and highlights bearing impulsive failures by measuring short-term spectral components. The method proposed in this paper aims to analyze nonstationary signals more efficiently under variable-speed conditions and shows promising results in emphasizing bearing failures with impulse behavior.
APPLIED SCIENCES-BASEL
(2021)
Article
Chemistry, Multidisciplinary
Feng Li, Shujin Yuan, Fanfan Qian, Zhizheng Wu, Huayan Pu, Min Wang, Jiheng Ding, Yi Sun
Summary: An adaptive active vibration control system is proposed to improve isolation performance of passive isolation structure, utilizing a Youla parameterized adaptive regulator and recursive least square algorithm to suppress multifrequency vibration disturbances. Experimental results demonstrate effective suppression of residual vibration, achieving over 20 dB reduction in combined multiple frequencies and quick response time.
APPLIED SCIENCES-BASEL
(2021)
Review
Engineering, Multidisciplinary
Nour A. Marey, Amman A. Ali
Summary: A multi-purpose Universal Journal Bearing Test Rig (UJBTR) was designed and constructed, and a fully controlled system for UJBTR was introduced. The system enables the acquisition of tribological values and the verification of obtained outcomes. It can conduct different test trials to investigate the operational factors affecting lubricating oil film performance. The results assure the reliability and ability of UJBTR for further investigations in hydrodynamic lubrication within journal bearing.
ALEXANDRIA ENGINEERING JOURNAL
(2023)
Article
Acoustics
Chuanbing Zhang, Hongrui Ao, Hongyuan Jiang, Yongliang Wang
Summary: This paper investigates the nonlinear dynamic behavior of a gas dynamic bearing-rotor system with a flexible supporting structure. By establishing a fractional-order dynamic model and using a tracking-alarming method, the stable and unstable regions of the rotational speed ratio are obtained, and the effects of the rotational speed ratio and fractional order on the dynamic behavior are studied.
JOURNAL OF VIBRATION AND CONTROL
(2022)
Article
Acoustics
Oleg Gaidai, Yu Wu, Ivan Yegorov, Panagiotis Alevras, Junlei Wang, Daniil Yurchenko
Summary: The paper investigates a strategy of nonlinear vibration mitigation using a passive absorber for a variable length pendulum. Numerical studies validate the proposed strategy and demonstrate high performance of the nonlinear passive absorber when properly tuned.
JOURNAL OF VIBRATION AND CONTROL
(2022)
Article
Engineering, Civil
Dida Wang, Xi Wang, Yang Zhang, Tao Wang, Guoqiang Fu, Caijiang Lu
Summary: This paper focuses on optimizing the parameters of an electromagnetic vibration absorber to control low and variable frequency vibrations, leading to improved performance. The simulations and experiments demonstrate the effectiveness of the optimized absorber in controlling vibrations within a wide low-frequency range.
INTERNATIONAL JOURNAL OF STRUCTURAL STABILITY AND DYNAMICS
(2022)
Article
Engineering, Mechanical
Seon-Jun Jang, Michael J. Brennan, Fadi Dohnal, Yoon-Pyo Lee
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART C-JOURNAL OF MECHANICAL ENGINEERING SCIENCE
(2017)
Article
Engineering, Mechanical
Athanasios Chasalevris
TRIBOLOGY INTERNATIONAL
(2016)
Article
Automation & Control Systems
Fadi Dohnal
Article
Engineering, Mechanical
Athanasios Chasalevris, Gilles Guignier
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART C-JOURNAL OF MECHANICAL ENGINEERING SCIENCE
(2019)
Article
Engineering, Mechanical
Thomas Breunung, Fadi Dohnal, Bastian Pfau
NONLINEAR DYNAMICS
(2019)
Article
Mechanics
Miguel Ramirez-Barrios, Fadi Dohnal, Joaquin Collado
ARCHIVE OF APPLIED MECHANICS
(2020)
Article
Engineering, Mechanical
Athanasios Chasalevris
TRIBOLOGY INTERNATIONAL
(2020)
Article
Engineering, Chemical
Lukas Hafner, Steffen Schwarzer, Fadi Dohnal
Summary: Investigated the bubble formation mechanisms for oil/air media combination and found significant differences compared to water/air combination. The results obtained will help to design bubble columns in a more targeted manner in the future, leading to resource and energy savings in industrial test stands.
CHEMIE INGENIEUR TECHNIK
(2021)
Review
Nanoscience & Nanotechnology
Ota Samek, Silvie Bernatova, Fadi Dohnal
Summary: The ability to rapidly and reliably identify and characterize microorganisms from tiny sample volumes is crucial in the diagnostics of microbial infections. Surface enhanced Raman scattering (SERS) has shown great potential in providing a rapid and accurate method for diagnosing infections, with a focus on bacteria. SERS spectra of bacteria, generated from secreted metabolic substances, offer a valuable tool in differentiating cell types and physiological states, and have the potential for routine point-of-care tests in clinical settings.
Article
Engineering, Mechanical
Panagiotis Papafragkos, Ioannis Gavalas, Ioannis Raptopoulos, Athanasios Chasalevris
Summary: This study identifies the dissipating work in gas foil bearings as the source of self-excited motions in high-speed rotor systems. By optimizing design parameters, especially the properties of bump foils, bifurcations can be eliminated and system stability can be improved.
NONLINEAR DYNAMICS
(2023)
Article
Engineering, Chemical
Lukas Hafner, Martin Brunner, Nadja Konrad, Steffen Schwarzer, Fadi Dohnal
Summary: A physical model-based approach is proposed to accelerate the design of liquid-gas mixtures and control their quality.
CHEMICAL ENGINEERING RESEARCH & DESIGN
(2023)
Proceedings Paper
Engineering, Mechanical
Ricardo Ugliara Mendes, Fadi Dohnal
PROCEEDINGS OF THE 10TH INTERNATIONAL CONFERENCE ON ROTOR DYNAMICS - IFTOMM, VOL. 4
(2019)
Article
Engineering, Mechanical
Athanasios Chasalevris, Jean-Charles Louis
Article
Engineering, Manufacturing
E. Abele, F. Dohnal, M. Feulner, T. Sielaff, C. Daume
PRODUCTION ENGINEERING-RESEARCH AND DEVELOPMENT
(2018)
Proceedings Paper
Engineering, Mechanical
Fadi Dohnal
SCHWINGUNGEN 2017: BERECHNUNG, UBERWACHUNG, ANWENDUNG
(2017)
Article
Engineering, Mechanical
Xuanen Kan, Yanjun Lu, Fan Zhang, Weipeng Hu
Summary: A blade disk system is crucial for the energy conversion efficiency of turbomachinery, but differences between blades can result in localized vibration. This study develops an approximate symplectic method to simulate vibration localization in a mistuned bladed disk system and reveals the influences of initial positive pressure, contact angle, and surface roughness on the strength of vibration localization.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2024)
Article
Engineering, Mechanical
Zimeng Liu, Cheng Chang, Haodong Hu, Hui Ma, Kaigang Yuan, Xin Li, Xiaojian Zhao, Zhike Peng
Summary: Considering the calculation efficiency and accuracy of meshing characteristics of gear pair with tooth root crack fault, a parametric model of cracked spur gear is established by simplifying the crack propagation path. The LTCA method is used to calculate the time-varying meshing stiffness and transmission error, and the results are verified by finite element method. The study also proposes a crack area share index to measure the degree of crack fault and determines the application range of simplified crack propagation path.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2024)
Article
Engineering, Mechanical
Rongjian Sun, Conggan Ma, Nic Zhang, Chuyo Kaku, Yu Zhang, Qirui Hou
Summary: This paper proposes a novel forward calculation method (FCM) for calculating anisotropic material parameters (AMPs) of the motor stator assembly, considering structural discontinuities and composite material properties. The method is based on multi-scale theory and decouples the multi-scale equations to describe the equivalence and equivalence preconditions of AMPs of two scale models. The effectiveness of this method is verified by modal experiments.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2024)
Article
Engineering, Mechanical
Hao Zhang, Jiangcen Ke
Summary: This research introduces an intelligent scheduling system framework to optimize the ship lock schedule of the Three Gorges Hub. By analyzing navigational rules, operational characteristics, and existing problems, a mixed-integer nonlinear programming model is formulated with multiple objectives and constraints, and a hybrid intelligent algorithm is constructed for optimization.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2024)
Article
Engineering, Mechanical
Jingjing He, Xizhong Wu, Xuefei Guan
Summary: A sensitivity and reliability enhanced ultrasonic method has been developed in this study to monitor and predict stress loss in pre-stressed multi-layer structures. The method leverages the potential breathing effect of porous cushion materials in the structures to increase the sensitivity of the signal feature to stress loss. Experimental investigations show that the proposed method offers improved accuracy, reliability, and sensitivity to stress change.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2024)
Article
Engineering, Mechanical
Benyamin Hosseiny, Jalal Amini, Hossein Aghababaei
Summary: This paper presents a method for monitoring sub-second or sub-minute displacements using GBSAR signals, which employs spectral estimation to achieve multi-dimensional target detection. It improves the processing of MIMO radar data and enables high-resolution fast displacement monitoring from GBSAR signals.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2024)
Article
Engineering, Mechanical
Xianze Li, Hao Su, Ling Xiang, Qingtao Yao, Aijun Hu
Summary: This paper proposes a novel method for bearing fault identification, which can accurately identify faults with few samples under complex working conditions. The method is based on a Transformer meta-learning model, and the final result is determined by the weighted voting of multiple models.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2024)
Article
Engineering, Mechanical
Xiaomeng Li, Yi Wang, Guangyao Zhang, Baoping Tang, Yi Qin
Summary: Inspired by chaos fractal theory and slowly varying damage dynamics theory, this paper proposes a new health monitoring indicator for vibration signals of rotating machinery, which can effectively monitor the mechanical condition under both cyclo-stationary and variable operating conditions.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2024)
Article
Engineering, Mechanical
Hao Wang, Songye Zhu
Summary: This paper extends the latching mechanism to vibration control to improve energy dissipation efficiency. An innovative semi-active latched mass damper (LMD) is proposed, and different latching control strategies are tested and evaluated. The latching control can optimize the phase lag between control force and structural response, and provide an innovative solution to improve damper effectiveness and develop adaptive semi-active dampers.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2024)
Article
Engineering, Mechanical
Menghao Ping, Xinyu Jia, Costas Papadimitriou, Xu Han, Chao Jiang, Wang-Ji Yan
Summary: Identification of non-Gaussian processes is a challenging task in engineering problems. This article presents an improved orthogonal series expansion method to convert the identification of non-Gaussian processes into a finite number of non-Gaussian coefficients. The uncertainty of these coefficients is quantified using polynomial chaos expansion. The proposed method is applicable to both stationary and nonstationary non-Gaussian processes and has been validated through simulated data and real-world applications.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2024)
Article
Engineering, Mechanical
Lei Li, Wei Yang, Dongfa Li, Jianxin Han, Wenming Zhang
Summary: The frequency locking phenomenon induced by modal coupling can effectively overcome the dependence of peak frequency on driving strength in nonlinear resonant systems and improve the stability of peak frequency. This study proposes the double frequencies locking phenomenon in a three degrees of freedom (3-DOF) magnetic coupled resonant system driven by piezoelectricity. Experimental and theoretical investigations confirm the occurrence of first frequency locking and the subsequent switching to second frequency locking with the increase of driving force. Furthermore, a mass sensing scheme for double analytes is proposed based on the double frequencies locking phenomenon.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2024)
Article
Engineering, Mechanical
Kai Ma, Jingtao Du, Yang Liu, Ximing Chen
Summary: This study explores the feasibility of using nonlinear energy sinks (NES) as replacements for traditional linear tuned mass dampers (TMD) in practical engineering applications, specifically in diesel engine crankshafts. The results show that NES provides better vibration attenuation for the crankshaft compared to TMD under different operating conditions.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2024)
Article
Engineering, Mechanical
Wentao Xu, Li Cheng, Shuaihao Lei, Lei Yu, Weixuan Jiao
Summary: In this study, a high-precision hydraulic mechanical stand and a vertical mixed-flow pumping station device were used to conduct research on cavitation signals of mixed-flow pumps. By analyzing the water pressure pulsation signal, it was found that the power spectrum density method is more sensitive and capable of extracting characteristics compared to traditional time-frequency domain analysis. This has significant implications for the identification and prevention of cavitation in mixed-flow pump machinery.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2024)
Article
Engineering, Mechanical
Xiaodong Chen, Kang Tai, Huifeng Tan, Zhimin Xie
Summary: This paper addresses the issue of parasitic motion in microgripper jaws and its impact on clamping accuracy, and proposes a symmetrically stressed parallelogram mechanism as a solution. Through mechanical modeling and experimental validation, the effectiveness of this method is demonstrated.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2024)
Article
Engineering, Mechanical
Zhifeng Shi, Gang Zhang, Jing Liu, Xinbin Li, Yajun Xu, Changfeng Yan
Summary: This study provides useful guidance for early bearing fault detection and diagnosis by investigating the effects of crack inclination and propagation direction on the vibration characteristics of bearings.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2024)