Vibration control of a rotor supported by journal bearings and an asymmetric high-static low-dynamic stiffness suspension

A hydrodynamic lubrication analysis for connecting rod big-end bearing is conducted. The effects of engine speed, operating condition, lubricant viscosity and oil temperature on tribological performance of big-end bearing have been examined. Force equilibrium is solved to define instantaneous eccentricity between journal and bearing to have accurate estimation of oil film thickness at interface of connecting rod big-end bearing and crankpin. Connecting rod big-end is treated as π film hydrodynamic journal bearing and finite difference scheme is applied to calculate generated hydrodynamic pressure and frictional power loss at each crank angle. Beside the development of analytical formulation, well-known Mobility model introduced by Booker has been employed to be compared with the analytical model. The presented analytical model reduces the complexity and the numerical effort with respect to Mobility method, thus shortening the computation time. The simulation results show good agreement between analytical model, Mobility approach and experimental data.

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“…Substituting Equation (17) in Equation (18) and performing the derivatives, the expression of hydrodynamic pressure can be obtained:…”

Section: Numerical Solutionmentioning

confidence: 99%

“…The effects of nonlinear suspensions of a rotor bearing system on the bearing dynamic response have been studied considering short bearing approximation. The complex dynamic responses of the rotating system components were detected using numerical simulations [17].…”

Section: Introductionmentioning

confidence: 99%

Numerical Study of Power Loss and Lubrication of Connecting Rod Big-End

2019

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“…e model in this paper is a massless shaft with a disk supported by a pair of self-acting gas journal bearings. Generally speaking, the manufacture precision of rotors is always better than that of bearings, so, the waves on the surface of rotors can be neglected [22]. In this paper, the journal bearings used for calculation include axial and circumferential surface waviness which is shown in Figure 1.…”

Section: Numerical Solution Of Gas Pressure Distributionmentioning

confidence: 99%

“…Hassini and Arghir [21] used the dynamic coefficients to analyze the nonlinear characteristics, and the results were in good agreement with the results calculated by nonlinear transient Reynolds equations. Abbasi et al [22] studied the vibration control of the rotating machine with a high-static low-dynamic stiffness suspension. In their study, the complex nonlinear dynamic behavior was showed, and the results present that the method can suppress the nonperiodic behavior in the considered speed range.…”

Section: Introductionmentioning

confidence: 99%

Effects of Surface Waviness on the Nonlinear Vibration of Gas Lubricated Bearing‐Rotor System

Sheng

et al. 2018

Shock and Vibration

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This paper presents the effects of the surface waviness on the nonlinear dynamic performance of a gas bearing-rotor system. The coupled vibration with the elastomer is taken into consideration to fit the actual engineering application. The effects of the directions, the amplitudes, and the numbers of waves to the nonlinear dynamic performance are investigated. The results show that the existence of the surface waviness in the circumferential direction can improve the stability of the system obviously. But the surface waviness in the axial direction is damage to the system. The nonlinear dynamic performance of the system is insensitive to the number of surface waviness. The increase of the amplitude of the waviness in circumferential direction can improve the stability of the system.

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“…Studies of QZS vibration isolation have focused on translational and vertical vibration. Regarding non-linear vibration isolation, harmonic response, jump phenomena, chaotic motion, resonance, and transmissibility have been deeply explored [27][28][29][30]. Recently, QZS vibration isolation has been introduced into the field of torsional vibration isolation through the constitution of a high-static-low-dynamic torsional stiffness unit.…”

Section: Introductionmentioning

confidence: 99%

A Novel Dual–Parallelogram Passive Rocking Vibration Isolator: A Theoretical Investigation and Experiment

Wang

Gao

et al. 2017

Applied Sciences

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Vibration isolators with quasi-zero stiffness (QZS) perform well for low-or ultra-low-frequency vibration isolation. This paper proposes a novel dual-parallelogram passive rocking vibration isolator with QZS that could effectively attenuate in-plane disturbances with low-frequency vibration. First, a kinematic model of the proposed vibration isolator was established and four linear spring configuration schemes were developed to implement the QZS. Next, an optimal scheme with good high-static-low-dynamic stiffness (HSLDS) performance was obtained through comparison and analysis, and used as a focus for the QZS model. Subsequently, a dynamic model-based Lagrangian equation that considered the spring stiffness and damping and the influence of the payload gravity center on the vibration isolation system was developed, and an average approach was used to analyze the vibration transmissibility. Finally, the prototype and test system were constructed. A comparison of the simulation and experimental results showed that this novel passive rocking vibration isolator could bolster a heavy payload. Experimentally, the vibration amplitude decreased by 53% and 86% under harmonic disturbances of 0.08 Hz and 0.35 Hz, respectively, suggesting the great practical applicability of this presented vibration isolator.

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Vibration control of a rotor supported by journal bearings and an asymmetric high-static low-dynamic stiffness suspension

Cited by 36 publications

References 40 publications

Numerical Study of Power Loss and Lubrication of Connecting Rod Big-End

Numerical Study of Power Loss and Lubrication of Connecting Rod Big-End

Effects of Surface Waviness on the Nonlinear Vibration of Gas Lubricated Bearing‐Rotor System

A Novel Dual–Parallelogram Passive Rocking Vibration Isolator: A Theoretical Investigation and Experiment

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