Article
Engineering, Mechanical
Jiasheng Huang, Kuanyong Zhou, Wei Chen, Hanwen Song
Summary: The paper discusses the limitations of DIC algorithms in large rotation cases and introduces the Phase Mapping Method (PMM) to improve the efficiency of initial parameter guessing. By rearranging images and introducing a fast phase detection approach to automate PMM, the success rate and efficiency of DIC algorithms can be significantly improved.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2021)
Article
Engineering, Mechanical
Laihao Yang, Zhu Mao, Xuefeng Chen, Ruqiang Yan, Jinsong Xie, Haifeng Hu
Summary: This study focuses on the coupling vibration mechanism of RSDB system, establishing a comprehensive dynamic model and theoretically interpreting the coupling mechanism. Numerical investigations reveal the significant effects of structure parameters on the coupling vibrations, and suggest that the analytical analysis and numerical study results can be cross-verified.
MECHANISM AND MACHINE THEORY
(2022)
Article
Chemistry, Physical
Peter Frankovsky, Ingrid Delyova, Peter Sivak, Jozef Bocko, Jozef Zivcak, Michal Kicko
Summary: This paper discusses a new approach for experimentally determining modal parameters using the non-contact optical method of digital image correlation. The approach utilizes a newly developed application module that can construct a frequency response function based on measured displacement values, allowing for the determination of modal parameters. The module has been designed for practical use in Scilab 6.1.0 and interfaces directly with the ISTRA4D high-speed camera software. The accuracy of the computational algorithm and obtained modal parameters were verified through simulation in Abaqus, showing high agreement with the results of the application.
Article
Thermodynamics
Ji-Huan He, T. S. Amer, W. S. Amer, H. F. Elkafly, A. A. Galal
Summary: This paper studies the dynamical properties of a rotating rigid body with a viscous incompressible fluid. By assuming a small Reynolds number, the governing equations are derived and solved using asymptotic techniques. The theoretical analysis reveals how the body parameter values affect the motion's behavior, providing insights for optimization of the charged rigid body.
INTERNATIONAL JOURNAL OF NUMERICAL METHODS FOR HEAT & FLUID FLOW
(2023)
Article
Mathematics, Applied
Javad Taghipour, Morteza Dardel, Mohammad Hadi Pashaei
Summary: This study investigates the nonlinear dynamics of a rotor system with a flexible rotor shaft carrying an unbalanced rigid disc. Three different rotor systems are analyzed, and a two-mode reduced order model is used to study the nonlinear dynamics. The study utilizes the extended Hamilton principle to derive nonlinear equations of motion and employs numerical integration to solve the resulting equations. The effects of various parameters on the dynamic behavior of the structure are investigated, including the chaotic response of the system.
COMMUNICATIONS IN NONLINEAR SCIENCE AND NUMERICAL SIMULATION
(2021)
Article
Chemistry, Analytical
Zhonghan Liang, Yuxiang Zhang, Lin Yue
Summary: This study combines the non-contact optical techniques of digital image correlation (DIC) and blade tip-timing (BTT) to achieve a method of investigation for a rotating blade vibration measurement. Results show that this method is an effective non-contact, high-precision full-field deformation measurement method that is worth exploring for structural design and dynamic strain assessment of vibrating components.
Article
Engineering, Multidisciplinary
Tian Yu Zhao, Yu Ma, Hong Yuan Zhang, Hong Gang Pan, Yi Cai
Summary: This paper investigates the coupled modeling method and free vibration characteristics of a graphene nanoplatelet reinforced blade-disk rotor system, discussing the effects of various parameters such as rotating speed, GPL distribution pattern, weight fraction, length-to-thickness ratio, length-to-width ratio, and geometric features of the components on the free vibration characteristics.
APPLIED MATHEMATICAL MODELLING
(2021)
Article
Mechanics
Lokanna Hoskoti, Ajay Misra, Mahesh M. Sucheendran
Summary: This study presents the free vibration analysis of a twisted, double-tapered blade mounted on a rotating disk undergoing overall motion using the Lagrangian approach. The modal characteristics of the blade are studied and the equations governing the coupled motion of the rotating blade are derived and solved for the eigenvalue problem. The results show the variation of natural frequencies with rotating speed, taper ratio and pre-twist angle, as well as the investigation of resonance phenomenon.
ARCHIVE OF APPLIED MECHANICS
(2021)
Article
Engineering, Mechanical
Jialiang Sun, Zhengzheng Cai, Jiahao Sun, Dongping Jin
Summary: This paper studies the influence of control moment gyroscopes (CMGs) on the dynamic responses and characteristics of an inflatable space structure. The large deformations and motions of the inflatable tubes and rigid satellites are accurately described using the absolute nodal coordinate formulation (ANCF) and the natural coordinate formulation (NCF) respectively. A detailed rigid body dynamic model of the CMG is proposed, which can be attached to and coupled with any flexible body. The orbital dynamic equations of the inflatable space structure coupled with distributed CMGs are derived and the dynamic characteristics are analyzed.
NONLINEAR DYNAMICS
(2023)
Article
Chemistry, Multidisciplinary
Xavier Regal, Gwendal Cumunel, Michel Bornert, Marc Quiertant
Summary: In this study, the free vibration of a beam triggered by a shock is investigated using a high-speed camera and digital image correlation. The beam displacement fields are deduced from the images and the modal parameters are computed using a continuous wavelet transform method. The results obtained with this method are compared with those obtained using accelerometers and the beam theory.
APPLIED SCIENCES-BASEL
(2023)
Article
Engineering, Aerospace
Fan Jiang, Liang Li, Wei-Hsin Liao, Dingguo Zhang
Summary: A rigid-flexible coupled dynamic model for a rotating hub-plate with enhanced active constrained layer damping (EACLD) treatment is established, considering the coupling effect of transverse bending and in-plane stretching. Analysis of numerical simulation and vibration control performance show that EACLD treatment behaves better than traditional ACLD configuration in terms of vibration controllability.
AEROSPACE SCIENCE AND TECHNOLOGY
(2021)
Article
Mechanics
Abdallah Daddi-Moussa-Ider, Alexander R. Sprenger, Thomas Richter, Hartmut Loewen, Andreas M. Menzel
Summary: Geometric confinements have a significant impact on the rheology and behavior of colloidal suspensions at low Reynolds numbers. The study investigates the viscous azimuthal flow induced by the slow rotation of a small spherical particle near a rigid disk or between two coaxial disks. Solutions are formulated as mixed-boundary-value problem and transformed into integral equations, with analytical and numerical methods used for solving. The results provide insights into the hydrodynamic mobility and system geometry effects on the slow rotational motion of colloidal particles, showing good agreement with finite-element simulations.
Article
Acoustics
Jun Wu, Branislav Titurus
Summary: A new vibration suppression method is proposed in this paper for a rotating Timoshenko beam axially loaded by a tendon with the inerter-damper guiding elements. The effectiveness of vibration suppression is closely related to the optimal tuning strategy and the use of inerter-dampers as guiding elements.
JOURNAL OF SOUND AND VIBRATION
(2022)
Article
Acoustics
Aisha Javed, Jueon Park, Hyeongill Lee, Youkyung Han
Summary: Vibration analysis is widely used for structural health monitoring. Traditional contact-type sensors can degrade the performance of lightweight structures, so image-based non-contact sensors have been proposed. This study introduces a non-contact vibration signal separation technique to identify multiple factors causing vibrations at different frequencies in a structure. The technique detects vibrations using an edge-based measurement and uses motion magnification to generate magnified videos at different frequencies for separating vibration signals.
JOURNAL OF SOUND AND VIBRATION
(2023)
Article
Engineering, Aerospace
A. Pagani, R. Azzara, E. Carrera, E. Zappino
Summary: This research presents important results from a test campaign on the Dardo Aspect, emphasizing the reliability of innovative techniques while acknowledging potential calibration and testing preparation issues. These methods, although not suitable for certification purposes, offer significant time and cost benefits.
AEROSPACE SCIENCE AND TECHNOLOGY
(2021)
Article
Chemistry, Multidisciplinary
Robert Hunady, Pavol Lengvarsky, Peter Pavelka, Adam Kal'avsky, Jakub Mlotek
Summary: The paper discusses methods of equivalence of boundary conditions in finite element models based on the finite element model updating technique. The proposed methods involve determining stiffness parameters in the section plate or region to replace the boundary condition or removed part of the model with a bushing connector. Two methods for determining elastic properties are described, one based on static finite element analyses and the other a combination of experimental and numerical approaches. These methods provide a good estimate of stiffness at the region where the model is replaced by an equivalent boundary condition, increasing accuracy and saving computational time.
APPLIED SCIENCES-BASEL
(2021)
Article
Chemistry, Multidisciplinary
Miroslav Pastor, Pavol Lengvarsky, Martin Hagara, Alzbeta Sapietova, Patrik Sarga
Summary: Preloaded bolted connections are commonly used for anchoring steel structures and equipment, requiring prescribed tightening procedures for safe operation. This study focused on anchoring a new casting pedestal using original anchor bolts, assessing the reliability of the anchoring system under cyclic stress. The authors utilized experimental measurements and numerical modeling to determine the lifespan of the anchoring system under loading cycles.
APPLIED SCIENCES-BASEL
(2021)
Article
Chemistry, Physical
Peter Palicka, Robert Hunady, Martin Hagara, Pavol Lengvarsky
Summary: This work aims to optimize the mounting process of the tire apex to the bead, minimizing the risk of rim slip and ensuring driving stability. Through simulation and optimization, recommendations for producing suitable apex shapes are provided.
Article
Chemistry, Physical
Adam Kalavsky, Adam Nieslony, Robert Hunady
Summary: This paper analyzes the influence of the Welch method on fatigue life estimation in the frequency domain. It examines the impact of parameters such as window size, weighting, and overlap on power spectral density (PSD) calculation and lifetime estimation. Four different reference PSD spectra are generated and tested to demonstrate the general validity of the conclusions. The study finds that the best configuration of Welch method parameters for fatigue calculations is selecting the smallest possible time window (up to 60% of observation length) and the largest possible overlap (at least 70% of window size).
Article
Engineering, Multidisciplinary
Michal Fabian, Robert Hunady, Tomas Mlaka, Frantisek Kupec
Summary: This paper discusses the possibilities of reducing aerodynamic drag and modifying airflow in the rear of a hatch-back vehicle. The study proposes different spoiler designs and evaluates their effects on flow parameters through CFD analysis and simulations.
ADVANCES IN SCIENCE AND TECHNOLOGY-RESEARCH JOURNAL
(2022)
Article
Engineering, Manufacturing
Michal Fabian, Robert Hunady, Frantisek Kupec
Summary: This article discusses the application of Reverse Engineering and Rapid Prototyping processes in the automotive industry, focusing on the design of the exterior rear view mirror. Data about the shape and modeling of the part were obtained through laser scanning and processed in CATIA software. The print data of the mirror was generated using Rapid Prototyping technology, specifically ABS material and FDM method.
MANUFACTURING TECHNOLOGY
(2022)
Article
Engineering, Mechanical
Jozef Bocko, Miroslav Pastor, Martin Hagara, Pavol Lengvarsky
Summary: The article describes gate valves used in water dams, which experienced problems with hydraulic actuation and required manual operation. Operational measurements and strength analysis revealed the need for driving units with higher torque for safe and reliable operation.
ENGINEERING FAILURE ANALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Martin Hagara, Robert Hunady, Pavol Lengvarsky, Michal Vocetka, Peter Palicka
Summary: Combining the drilling and digital image correlation (DIC) methods is becoming popular for faster measurement and evaluation of strain relief. However, it is important to consider the potential factors that may affect the accuracy of DIC-based strain/stress analysis. This paper investigates the influence of the 3D DIC system's calibration procedure and image brightness on strain/stress analysis, using a specimen with a hole loaded with different levels of tensile force. The findings suggest that both factors can negatively impact the results, and recommend the use of a highly precise calibration target matched to the field of view and adjusting image brightness within a specific grey value range for optimal accuracy.
APPLIED SCIENCES-BASEL
(2023)
Article
Engineering, Aerospace
Marek Ceskovic, Martin Schrotter, Robert Hunady, Pavol Kurdel, Natalia Gecejova
Summary: A helicopter in flight experiences unwanted vibrations from multiple sources, leading to the degradation of its structural and functional components. Partial damage to antenna elements with vertical polarization uncovered additional vibrations caused by unwanted electromagnetic oscillations. These oscillations were detected during communication between the helicopter crew and air traffic control, and their negative influence was confirmed through measurements and modal analysis. The obtained results provide a theoretical and practical basis for monitoring this phenomenon and determining the health status of medium-heavy helicopters.
Article
Chemistry, Multidisciplinary
Miroslav Pastor, Pavol Lengvarsky, Martin Hagara, Jozef Kul'ka
Summary: This study assessed the remaining service life of a bridge crane using experimental measurement methods and identified a significant decrease in the life of one main girder due to non-compliance with design specifications. The importance of experimental measurements and selecting appropriate measurement locations were highlighted.
APPLIED SCIENCES-BASEL
(2022)
Article
Engineering, Mechanical
Robert Hunady, Michal Fabian, Pavol Lengvarsky, Albert Mares, Frantisek Kupec
Summary: This paper discusses the importance of numerical analysis and experimental tests in the design process of car wheels to ensure they meet safety standards and performance requirements.
INTERNATIONAL JOURNAL OF VEHICLE DESIGN
(2021)
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)