Dynamic stability of unbalance-induced vibration in a turbocharger rotor-bearing system with the nonlinear effect of thermal turbulent lubricating fluid film

Zhang, Yi; Wang, Wei; Wei, Daogao; Wang, Gang; Xu, Jimin; Liu, Kun

doi:10.1016/j.jsv.2022.116909

Cited by 24 publications

(7 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Особливістю коливань таких валів є те, що прогин перетину валу, де прикріплений диск, супроводжується поворотом перетину, тому відхилення центру валу супроводжується поворотом площини диску і, відповідно, одночасно відбувається прецесія центру валу та кутова прецесія диску. Кутова прецесія диску, яка викликає додаткові сили в наслідок гіроскопічної дії диску розглянуті в роботі [19], [20], [21]. Якщо швидкість обертання валу та моменти інерції насаджених на нього дисків відносно невеликі, то частоти власних коливань валу практично співпадають з власними частотами валу який не обертається.…”

Section: аналіз літературних даних та постановка проблемиunclassified

“…Для побудови амплітудно-частотних характеристик було проведено три досліди. В одну з чашок ротора центрифуги HERMLE Z306 містився вантаж з різними масами дисбалансу 3,2 г , 5,5 г, та без дисбалансу [12], [18], [20].…”

Section: експериментальне визначення динамічних характеристик центрифугиunclassified

See 1 more Smart Citation

The influence of imbalances on the dynamic characteristics of the laboratory centrifuge HERMLE Z306

Babenko,

Lavrenko

2024

Mech. Adv. Technol.

View full text Add to dashboard Cite

Laboratory centrifuges are used in various industries. During operation, vibrations occur that lead to resonant frequencies, which in turn impair functionality. This paper presents an overview of the computational model of the HERMLE Z306 laboratory centrifuge used in medical laboratories to separate mixtures of different fractions to determine the dynamic characteristics. The zones of stable operation of the centrifuge and the influence of the rotation speed on the natural frequencies are analytically determined. Experimental results are presented with the influence of imbalances on the dynamic characteristics of the HERMLE Z306 centrifuge. As a result of the modeling, the amplitude-frequency characteristics are determined and a Campbell diagram is constructed. Objective: Modeling of dynamic processes in laboratory centrifuges by studying the influence of imbalances on the quality of mixture separation. Determination of zones of stable operation of the centrifuge.Purpose: Construction of amplitude-frequency characteristics of the centrifuge, determination of zones of stable operation of the laboratory centrifuge during separation and Campbell diagram showing the dependence of natural frequencies on the rotation speed of the HERMLE Z306 centrifuge. This diagram makes it possible to determine the resonance zones. Methods of implementation: Based on the use of the Lagrange equation of the second kind, a model is obtained that makes it possible to determine the zones of stable operation of the centrifuge. Using experimental equipment, determine the frequency response of the centrifuge and analyze the Campbell diagram to determine the resonance zones.Results: The zones of stable operation of a laboratory centrifuge were analytically determined. The amplitude-frequency characteristics of the HERMLE Z306 centrifuge were constructed, the trajectories of the free end of the shaft were built taking into account the corresponding imbalances, and the resonance zones were experimentally determined. Conclusions: Experimental studies have shown that the free end of a laboratory centrifuge shaft moves along a surface whose shape and, accordingly, the path of movement depend on both the angles of rotation and translational movement that arise as a result of deformations of elastic supports. The analytical and experimental studies made it possible to identify unstable modes and thereby determine the areas of the centrifuge's operating modes. The separation process will be stable if the roots of the equation have a negative real part, and moreover, the motion will be asymptotically stable in the presence of resistance forces. An experimental technique for determining the dynamic parameters of the centrifuge has been developed. On its basis, the effect of the rotation speed on the natural frequencies was determined.

show abstract

Section: аналіз літературних даних та постановка проблемиunclassified

Section: експериментальне визначення динамічних характеристик центрифугиunclassified

The influence of imbalances on the dynamic characteristics of the laboratory centrifuge HERMLE Z306

Babenko,

Lavrenko

2024

Mech. Adv. Technol.

View full text Add to dashboard Cite

show abstract

“…1 In order to efficiently minimize bearing heat production and wear, the water film that WLB forms during normal operation prevents direct contact between the bearing and the journal. 2 However, the journal rotational speed is almost zero during the initial stage of startup, and the asperity contact, which is in the mixed lubrication state, primarily supports the bearing load. As the rotational speed is increased further, the bearing system is typically in a state of turbulent lubrication due to the joint effects of the low-viscosity fluid and the large relative slip speed.…”

Section: Introductionmentioning

confidence: 99%

Effects of turbulence and bush wear on the transient tribo-dynamic characteristics of water-lubricated bearings

Chen,

Wang,

et al. 2024

Proceedings of the Institution of Mechanical Engineers, Part J:

View full text Add to dashboard Cite

This research proposes a transient mixed elastohydrodynamic model considering turbulence and bush wear, as well as the concept of contact work, to study the transient tribo-dynamic characteristics of water-lubricated bearings. The effects of turbulence, wear depth, and wear deviation angle on transient tribo-dynamic characteristics of water-lubricated bearings are investigated. The findings show that turbulence significantly affects the dynamics of stable conditions and enhances the hydrodynamic effect, but little affects the frictional contact behavior. An appropriate wear depth favors improving the tribo-dynamic characteristics of the water-lubricated bearings, but it deteriorates as the wear depth continuously increases. Negative deviation angles are better for minimizing contact work and enhancing rotor stability. The lubrication and dynamic properties of water-lubricated bearings can be enhanced through a rational approach to wear morphology design. This research is important for the optimal design and diagnosis of water-lubricated bearings wear failures.

show abstract

“…[8][9][10][11][12][13] As a result, numerical models for simulating the dynamic behavior of journal bearing start-up processes have gained popularity in recent years. [14][15][16][17] In recent years, the numerical prediction of bearings during start-up has become increasingly sophisticated. Cui et al incorporated the dynamic equations of the rotor into a mixed lubrication model and numerically investigated the dynamic contact behavior of a journal bearing during start-up, discussing the effects of relative clearance and acceleration time.…”

Section: Introductionmentioning

confidence: 99%

“…8–13 As a result, numerical models for simulating the dynamic behavior of journal bearing start-up processes have gained popularity in recent years. 14–17…”

Section: Introductionmentioning

confidence: 99%

Transient tribo-dynamic performance of journal bearings considering wear behavior during start-up

Wei

Liao

Wang

et al. 2023

Proceedings of the Institution of Mechanical Engineers, Part J:

Self Cite

View full text Add to dashboard Cite

The transient tribo-dynamics and wear model are coupled to study the mixed lubrication-wear behavior during start-up. The coupled numerical model involves the film thickness equation with wear depth and a time-varying wear coefficient to account for the impact of transient mixed lubrication behavior on wear. In this study, the evolution of wear and mixed lubrication performance distribution over time is predicted, and the impact of acceleration mode, acceleration time, external load, lubricant viscosity, and start-up time on the numerical predictions is evaluated. The findings demonstrate that wear behavior, particularly in the analysis of the effects of acceleration mode and acceleration time, has a significant impact on the evaluation of the bearing-rotor system's start-up performance and even changes the determination of optimal parameters. Furthermore, the parametric study demonstrates that wear and mixed lubrication performance are sensitive to the external load and lubricant viscosity. Finally, studies on the effect of start-up times show that proper wear geometry promotes hydrodynamic effects, but severely worn bearing surfaces have a negative effect on start-up.

show abstract

Dynamic stability of unbalance-induced vibration in a turbocharger rotor-bearing system with the nonlinear effect of thermal turbulent lubricating fluid film

Cited by 24 publications

References 37 publications

The influence of imbalances on the dynamic characteristics of the laboratory centrifuge HERMLE Z306

The influence of imbalances on the dynamic characteristics of the laboratory centrifuge HERMLE Z306

Effects of turbulence and bush wear on the transient tribo-dynamic characteristics of water-lubricated bearings

Transient tribo-dynamic performance of journal bearings considering wear behavior during start-up

Contact Info

Product

Resources

About