Study on Nonlinear Friction-Induced Vibration in Water-Lubricated Rubber Stern Tube Bearings

This paper is concerned with friction-induced vibration of a continuous propeller–shaft system excited by nonlinear friction due to contact between a water-lubricated bearing and a shaft. The dynamic equation is derived using Hamilton’s principle in conjunction with the finite element method. The drooping characteristics of the nonlinear friction and the torsional–lateral coupling via the bearing–shaft interaction laws are considered. Both stability analysis and responses analysis are then investigated through various system parameters. Stability is analyzed by determining the eigenvalues of the Jacobian matrix of the linearized system at the equilibrium point. Dynamic responses of the system are calculated on the basis of a reduced order modal model using the numerical integration method in order to validate the stability analysis. Numerical simulation proved to be consistent with the linear stability analysis. Analytical and numerical investigations reveal that friction-induced vibration of the proposed system is due to the combined action of nonlinear friction and coupled dynamics of the system, rather than the velocity-dependent friction alone as is commonly assumed.

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Experimental verification of the mechanism on stick-slip nonlinear friction induced vibration and its evaluation method in water-lubricated stern tube bearing

Ocean Engineering ◽

10.1016/j.oceaneng.2019.04.078 ◽

2019 ◽

Vol 182 ◽

pp. 147-161 ◽

Cited By ~ 6

Author(s):

Hyung Suk Han ◽

Kyoung Hyun Lee

Keyword(s):

Experimental Verification ◽

Evaluation Method ◽

Nonlinear Friction ◽

Stick Slip ◽

Friction Induced Vibration

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Piezoelectric-based dither control for automobile brake squeal suppression under various braking conditions

Journal of Vibration and Control ◽

10.1177/1077546320956765 ◽

2020 ◽

pp. 107754632095676

Author(s):

HweeKwon Jung ◽

Gyuhae Park ◽

Jeong Kyu Kim

Keyword(s):

Automotive Industry ◽

High Frequency ◽

Experimental Investigations ◽

Disc Brake ◽

Nonlinear Friction ◽

Frequency Range ◽

Brake Squeal ◽

Squeal Noise ◽

Piezoelectric Stack Actuator ◽

Friction Induced Vibration

Automobile brake squeal noise, which is nonlinear, friction-induced vibration in the frequency range 1–16 kHz, still remains a major problem for the automotive industry. This article presents analytical and experimental investigations into the application of dither control for active suppression of automobile disc brake squeal. Dither is a concept of active control that introduces high-frequency actuation into a system to suppress a much lower frequency disturbance. In this study, a specially designed brake system is built, in which a piezoelectric stack actuator in the piston of a floating caliper brake applies the dither input. In the experiments, squeal noise generated under the drag mode and various dynamic modes are considered. The results indicate that this piezoelectric-based dither control could effectively suppress the brake squeal noise by 5–10 dB and the squeal occurrence by up to 60% under various braking conditions.

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