Analysis Of Vibration Characteristics Research Articles

Dynamic modeling considering time-varying contact pairs and parameterized defects of deep groove ball bearings for its vibration characteristic analysis

Dynamic modeling considering time-varying contact pairs and parameterized defects of deep groove ball bearings for its vibration characteristic analysis

Analysis of Vibration Characteristics and Influencing Factors of Complex Tread Pattern Tires Based on Finite Element Method

The vibration of the tires significantly impacts a vehicle’s ride comfort and noise level; however, the current analysis of tire vibration characteristics often involves excessive simplification in their models, leading to a reduction in model accuracy. To analyze the tire vibrational properties and the influence of its design and service conditions, a combined modeling technology was developed to construct a three-dimensional (3D) finite element model of a 205/55R16 specification radial tire with intricate tread patterns. The accuracy and reliability of the simulation model was verified through vibration modal tests. Based on the vibration mode theory, the Lanczos method provided by ABAQUS was adopted to analyze the modal characteristics of the tire under free inflation and grounded conditions, and the effects of different inflation pressures, loads, operating conditions, and belt cord angles on the tire vibration characteristics were analyzed. The results indicate that grounding constraints will suppress the low order radial modal frequency of the tire and enhance the lateral modal frequency. The higher the order of the tire vibration mode, the greater the impact of inflation pressure. As the operating conditions change, the modal frequencies of all directions have the same trend of change, and as the ground load increases, the tire is prone to misalignment at lower lateral frequencies. The radial and lateral grounding modes of the tire are slightly affected by the change of the cord angle in the belt layer, but the circumferential grounding frequency decreases as the belt layer angle increases. These research findings offer a crucial foundation for the structural design of complex tread pattern tires, and also serve as a reference for addressing vibration and comfort issues encountered in the tire matching process.

Comparative analysis of static and vibration characteristics of glass fiber reinforced epoxy mono composite leaf spring and conventional steel leaf spring

Leaf springs play a vital role in heavy-duty vehicles by offering substantial load support, durability, and convenient maintenance. Lightweight leaf springs enhance vehicle performance, offering benefits like improved fuel efficiency and a smoother ride. Glass fiber reinforced composites enhance fuel efficiency and durability, providing corrosion resistance. Their design flexibility improves ride comfort, and damping properties enhance vehicle stability. The examination conducted through finite element analysis, utilizing ANSYS software, demonstrated a substantial 75.32% decrease in weight for the E-Glass-Epoxy composite leaf spring (GECLS), affirming its efficacy in enhancing strength, reducing weight, and enhancing stiffness. This underscores its superiority as a viable alternative to traditional steel leaf springs (SLS) in vehicular applications. The mono-GECLS exhibited a natural frequency that was found to be 1.9 times higher than that observed in the traditional SLS. It indicates the potential to mitigate resonance issues. After analysing the SLS and GECLS using ANSYS, it was observed that the GECLS exhibits greater values in deflection, natural frequency, and strain energy, measuring 4.659 mm, 29.98 Hz, and 440.68 mJ, respectively, compared to its steel counterpart. Conversely, the SLS demonstrates elevated values in stress, mass, and density, with readings of 283.84 MPa, 3.7695 kg, and 5920 kg/m³, respectively.

Analysis of Nonlinear Vibration Characteristics and Whirl Behavior of Dual-Rotor Systems with Inter-Shaft Rub Impact

Previous studies on rub-impact faults have mainly focused on the rub-impact between rotors and stators, with less research on inter-rotor rub impact. The impact of inter-rotor rub impact on rotor nonlinear vibration is particularly significant. This study investigates the effects of inter-shaft rub impact on the vibration characteristics and whirl behavior of dual-rotor systems. Initially, a dual-rotor model with inter-shaft bearings is established using the finite element method, and inter-shaft rub-impact forces are derived based on contact mechanics. Next, the system response is solved using the Newmark method. Vibration characteristics are analyzed through Campbell diagrams, 3D waterfall plots, time-frequency domain plots, and steady-state rub-impact force plots. Finally, the influence of inter-shaft rub impact on the whirl behavior of the dual-rotor system is studied based on the theory of full-spectrum analysis. The study concludes that inter-shaft rub-impact faults shift the system’s resonance points backward, increase harmonic and combination frequency components, and significantly affect the system response under dual-rotor co-rotation. Excessive friction can lead to self-excited vibrations and sudden amplitude increases, particularly in the LP rotor frequency. Additionally, inter-shaft rub impact primarily affects the whirl behavior of the LP-compressor disk1, showing multiple cycles of forward and backward whirl alternation during acceleration due to combined unbalanced and rub-impact excitations.

Uncertain stochastic vibration characteristic analysis of composite laminated rectangular plate based on improved kriging model

The stochastic vibration analysis of composite laminated structures has been conducted extensively in the field of structural dynamics. Existing studies in this field are primarily conducted based on deterministic structural parameters, whereas the effects of parametric uncertainties on the stochastic vibration characteristics of composite laminated structures are disregarded. This study investigates a composite laminated rectangular plate by considering the effect of interval uncertainty in the intrinsic parameters and load on its stochastic vibration characteristics. A rapid analysis model for the structural stochastic vibration characteristics is established based on an improved kriging model. Additionally, an innovative approach that combines the improved kriging model with intelligent optimization is proposed to solve problems pertaining to uncertainty-propagation analysis of structures. Based on this method, an uncertainty-propagation analysis of structural stochastic vibration responses is efficiently implemented. The effectiveness of the proposed method is demonstrated by comparing the results with those obtained from Monte Carlo simulation. The numerical results indicate that different uncertain factors exert varying degrees of effect on the stochastic vibration characteristics of the plate. Finally, the effects of density, elastic modulus ratio, fiber orientation and load on the interval fluctuation patterns of uncertain responses are discussed.

Analysis of friction-induced vibration and wear characteristics during high-speed train friction braking process

This study explored the evolution of friction-induced vibration (FIV) and wear in high-speed train friction braking through experiments, theoretical analysis, and numerical simulation. Experimental tests revealed that vibration behavior transitions from high-frequency modes at high speeds to low-frequency stick-slip at lower speeds. Theoretical analysis indicated that brake disc speed, coefficient of friction (COF), and contact stiffness affect system stability. Specifically, the system experiences high-frequency vibrations at high speeds due to mode coupling, and the friction block surface primarily undergoes abrasive wear mechanisms. At lower speeds, the system demonstrates low-frequency stick-slip vibrations induced by the combined effects of mode coupling and negative friction velocity slope (NFVS) characteristics, and the friction block surface mainly experiences adhesive wear mechanisms.

The Modeling Method for Vibration Characteristics Analysis of Composite-Laminated Rotationally Stiffened Plate

The composite-laminated rotationally stiffened plate is widely applied in aviation, aerospace, ship, machinery, and other fields. For structural design and optimization, to investigate the vibration characteristics is important. In this paper, a modeling method of composite-laminated rotationally plate is established. The first-order shear deformation theory (FSDT) and the modified Fourier series are applied to construct the admissible displacement function of the stiffened plate-coupled systems. On this basis, the energy function of composite-laminated rotationally stiffened plate is established. Combined with the artificial virtual spring technology, the proposed theory could be used to analyze the vibration characteristics of composite-stiffened plate-coupled systems with various classical boundary conditions or arbitrary elastic boundary conditions. The Rayleigh–Ritz method is used to solve the energy function. Thus, the vibration characteristics of the composite-laminated rotationally stiffened plate are obtained and analyzed. The correctness of the theoretical analysis model was verified through modal experiments. On this basis, the effect of some important parameters on the vibration characteristics of stiffened plate structures is studied, such as the number, thickness, and width of the laminated stiffener, varying structural parameters, and different boundary conditions. This study can provide the theoretical basis for the vibration and noise reduction of such structures.

Vibration characteristics of a bolted joint rotor-bearing system with rubbing and pedestal looseness coupled fault: Simulation and experiment

Rotor-stator rub and pedestal looseness are common faults in rotating machinery, such as large gas turbines that typically use bolted joint structures to fasten adjacent disks together. It is of great significance to investigate the vibration behaviors of the bolted joint rotor-bearing system with pedestal looseness and rubbing coupled fault, which can provide proofs for the fault diagnosis. In the present work, a dynamic model of the bolted joint rotor-bearing system with coupled fault is developed by using the finite element (FE) method, and then the vibration characteristic analysis is carried out. The rotor shafts that connected by the bolted joint element (BJE) are discretized as two sets of Timoshenko beam elements. The BJE is composed with four springs (two linear translational springs and two rotational springs with piecewise-linear stiffness). The interactions of rotor-stator contact are then modeled based on the Hertz contact theory and Coulomb's friction law, and the bearing forces are also calculated based on the Hertz contact theory. Moreover, the pedestal looseness fault is modeled through the piecewise-linear stiffness spring. The equations of motions of the bolted joint rotor-bearing system with coupled fault are then developed through FE theory and solved by the Newmark method. The dynamic responses are then calculated, and the frequency spectrums, bending stiffness of bolted joint, and vibration responses under different rotation speeds under the coupled fault are analyzed. The experimental study is finally conducted based on a bolted joint rotor test rig. Simulation results are in agreement with experiment results. The research results can provide a basis for understanding the rotor dynamic features of a bolted joint rotor system with coupled faults of rubbing and pedestal looseness.

Dynamic stiffness formulation for vibration characteristics analysis of bi-dimensional functionally graded annular plate of variational thickness

Dynamic stiffness formulation for vibration characteristics analysis of bi-dimensional functionally graded annular plate of variational thickness

Analysis of structural vibration characteristics of embankment dam based on DVMD–VDR

Analysis of structural vibration characteristics of embankment dam based on DVMD–VDR

Analysis of Vibration Characteristics and Failure Behavior of Hot-Dip Galvanizing Immersion Roller System in High-Temperature Zinc Pot

Analysis of Vibration Characteristics and Failure Behavior of Hot-Dip Galvanizing Immersion Roller System in High-Temperature Zinc Pot

Analysis of torsional vibration characteristics for wind turbine drivetrain under external excitation

Analysis of torsional vibration characteristics for wind turbine drivetrain under external excitation

Isogeometric Analysis for Nonlocal Vibration Characteristics of BFGP Curved Nanobeams with Variable Nonlocal Parameters

Isogeometric Analysis for Nonlocal Vibration Characteristics of BFGP Curved Nanobeams with Variable Nonlocal Parameters

Analysis of Vehicle-Bridge Coupling Vibration Characteristics of Curved Girder Bridges

When vehicles move on a bridge, the coupling effect between vehicles and bridges can affect driving safety and comfort, especially for curved bridges, therefore, choosing reasonable design parameters for curved bridges is crucial. In this article, a three-span curved continuous box-girder bridge was taken as the research object; the entire process of vehicle-bridge coupling vibration of highway curved girder bridges was conducted via numerical simulation and the vehicle-bridge coupling vibration analysis program Cmck 1.0 was developed. Then, the influence factors such as curvature radius, constraint mode, and vehicle characteristics on the vehicle-bridge coupling vibration of curved girder bridges were explored. The results showed that as the curvature radius increased, the dynamic response of the bridge offered a gradually decreasing trend and compared to the vertical dynamic response, the torsional response was more sensitive to the influence of the curvature radius. Different constraint methods significantly impacted the dynamic response of bridges, and the vertical and torsional dynamic responses of bridges under general constraint arrangement of straight bridges were increased compared to those under boundary conditions for curved beam bridges. As the axle load of the car decreases, the bridge mid-span vertical and torsional dynamic responses showed a decreasing trend. In contrast, the lateral dynamic response gradually increased.

Nonlinear Vibration and Stiffness Characteristics Analysis of Maglev Train Based on Cubic Displacement Control

A control strategy combining cubic displacement feedback nonlinear control and proportional-differential (PD) linear control is used to control the vibration performance of the maglev system. The maglev system is divided into positive stiffness maglev system, quasi-zero stiffness maglev system and negative stiffness maglev system according to the linear stiffness value of maglev system. Firstly, an improved multi-scale method is used to analyze the vibration characteristics of suspension in the positive stiffness state of the maglev system. Secondly, the influence of control parameters on train vibration amplitude and vibration center displacement under quasi-zero stiffness is studied. Finally, the vibration characteristics of the train when the maglev system is in negative stiffness are analyzed by numerical simulation. The maglev system exhibits the worst vibration performance under negative stiffness compared with positive stiffness and quasi-zero stiffness. The suspension frame is easy to enter the chaotic motion state, and its vibration center is easy to deviate from the equilibrium position and produce large displacement when the maglev system is in the negative stiffness state. The control results show that the control strategy combining the cubic displacement feedback nonlinear control with the PD linear control can make the maglev system exhibit better vibration characteristics under positive and quasi-zero stiffness.

Simulation analysis of flow field and vortex-induced vibration characteristics of submarine cable under single/parallel-laying mode

Due to the long-term erosion of current, the submarine cable buried on the seabed surface easily causes fatigue damage to the lead sheath, which gradually progresses with time. In this paper, a two-dimensional spring-damping vortex vibration model is established considering the effect of transverse flow and in-line flow. The vortex-induced vibration response of suspended submarine cables under the influence of different parameters is simulated by using the slice method based on nested grids. The simulation model is used to simulate the flow field characteristics and vortex-induced vibration response of submarine cables under single laying and parallel laying conditions. The fluid-solid coupling mechanism between fluid and structure and the interaction law of parallel laying submarine cables are analyzed. Our study overcame the difficulty in testing the vortex-induced vibration of submarine cables and provided a viable method and empirical support for investigating the vortex-induced vibration properties of submarine cables and fatigue analysis.

Analysis of Natural Vibration Characteristics of Modified Timoshenko Cracked Beam

This study utilizes the transfer matrix method to analyze the modified Timoshenko beam with and without cracks. The massless torsional spring is assumed to represent the section where the crack is located. The matrix equation is simplified using boundary conditions and solved using MATLAB. Additionally, the influence of different crack depths and positions on the first three natural frequencies is compared to finite element analysis using three common types of beams as examples. The results indicate that increasing the crack depth leads to a decrease in the natural frequency of the beam. However, the impact on certain specific positions is insignificant, with a maximum error between the two methods not exceeding 2.73%. Furthermore, the study investigates the influence of crack depth on natural frequency under different span-to-height ratios. The findings reveal that increasing the span-to-height ratio reduces the influence of crack depth on natural frequency, thereby validating the proposed method and its applicability in modified Timoshenko cracked beams.

Analysis of Coupled Vibration Characteristics of Linear-Angular and Parameter Identification

Abstract A steady-state sinusoidal and distortion-free excitation source is very important for the accuracy and consistency of the calibration parameters of micro-electro-mechanical systems (MEMS) inertial sensors. To solve the problem that the current MEMS inertial measurement unit (IMU) calibration device is unable to reproduce the spatial motion of linear and angular vibration coupling, research topics on the coupling vibration characteristics and parameter identification for an electromagnetic linear-angular vibration exciter are proposed. This research paper used Ampere’s law and Lorentz force to establish the analytical expressions for the electromagnetic force and electromagnetic torque of the electromagnetic linear-angular vibration exciter. Then, the main purpose of this paper is to establish uniaxial and coupled vibration electromechanical analogy models containing mechanical parameters based on the admittance-type electromechanical analogy principle, and the parameter identification model is also obtained by combining the impedance formula with the additional mass method. Finally, the validity of the coupling vibration characteristics and the parameter identification model are verified by the frequency response simulation and the additional mass method, and the relative error of each parameter identification is within 5% in this paper.

Theoretical analysis of vibration characteristics of high-speed cylindrical roller bearing with groove elastic supports

As a necessary support system of high-speed rotor system, the roller bearing with elastic support’s vibration characteristics directly affect the stability and safety of rotor system. At this point, the theoretical analysis of bearing performance under the assumption of rigid ring is obviously no longer applicable. In this paper, considering the elastic deformation of both cylindrical roller bearing outer ring and the groove elastic support, the dynamic differential equations of cylindrical roller bearing with the elastic support are established on the basis of rolling bearing dynamics, and the bearing’s vibration under different working conditions is analyzed. The theoretical analysis results show that the groove elastic support can effectively reduce the radial vibration of cylindrical roller bearing under high speed and large radial load. And the experimental results show that the test’s vibration is consistent with the simulation’s vibration, which proves the reliability of the dynamic model of cylindrical roller bearing with the groove elastic support proposed in this paper. This research gives a new method for improving the dynamic characteristics of high-speed cylindrical roller bearings, and the model presented in this paper provides a theoretical basis for the design and manufacture of cylindrical roller bearing with elastic support.

Analysis of mechanical properties and free vibrational characteristics of novel Grewia optiva/basalt fiber reinforced hybrid polymer composites

AbstractThis study emphasize on the fabrication and testing of Grewia optiva/Basalt fiber reinforced polymer composites for use in internal applications of automobiles and aircraft. The study investigates the use of Grewia optiva fiber (local plant based fiber) with Basalt fiber, where chopped Basalt fiber (6, 9, and 12 mm) is reinforced in polyester matrix in combination with Grewia optiva fiber. Composite test specimen are fabricated and analyzed using a smart actuation system to evaluate the free vibrational behavior of the composites experimentally. The impact of various parameters including length of the fiber and its weight percentage on the free vibrational behavior of composites is determined. The percentage of individual reinforced fiber is varied (0, 4, 8, and 12 wt.%) maintaining fiber weight % constant, that is, 12 wt.% of composite. The experimental results help to identify the variations in natural frequencies of Basalt/Grewia optiva fiber based composites. B12/GO0 demonstrate the natural frequency of 67 Hz and 44.71 MPa tensile strength for 12 mm fiber reinforced composites. The finding from this experimental work provide insights into the potential applications of Basalt/Grewia optiva fiber reinforced composites for automobile and air craft industries.