Analytical model of self-acting journal bearing subjected to base excitation for marine engine system

Abstract

Rotating machinery in marine engine systems experiences the base excitation from the vertical and horizontal swing movements of the ship. Too large a base motion can produce severe rotor–bearing system damage. The Reynolds equation including the effects of the base excitation on motion is derived, and the corresponding analytical model of nonlinear oil-film force based on the long- and short-length bearing assumptions is established in this article. The pressure distribution and nonlinear oil-film force of journal bearing with different forms of foundation movement are simulated by numerical simulation. The following three cases are studied: journal spin motion, journal circular whirl, and journal radial motion (pure squeeze). It indicates that foundation movement will remarkably affect the pressure distribution and nonlinear oil-film force of journal bearing, which cannot be ignored during analyzing the dynamics of journal bearing–rotor system for marine engine. This study will make the foundation for the dynamic study of rotor–bearing system considering the basement motion.

Keywords

Base excitation journal bearing oil-film pressure distribution nonlinear oil-film force

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References

Guang

. Retrospect and prospect to the research on rotordynamics. J Vib Eng 2002; 15: 1–9 (in Chinese).

San Andrés

Ryu

Niu

. Dynamic response of a rotor-hybrid gas bearing system due to base induced. In: ASME Turbo Expo 2010: power for land, sea, and air (GT2010), Glasgow, UK, 14–18 June 2010, paper no. GT2010-22277.

San Andrés

Chirathadam

. Identification of rotor dynamic force coefficients of a metal mesh foil bearing using impact load excitations. In: ASME Turbo Expo 2010: power for land, sea, and air (GT2010), Glasgow, UK, 14–18 June 2010, paper no. GT2010-22440.

Tan

Lee

Leng

GSB

. Dynamic stability of a radially rotating beam subjected to base excitation. Comput Method Appl M 1997; 146: 265–279.

Guangchi

Guang

Jianping

. Turbocharger rotor dynamics considering engine’s foundation excitation. J Vib Shock 2009; 28: 18–24 (in Chinese).

Tessarzik

Chiang

Badgley

. The response of rotating machinery to external random vibration. J Eng Ind: T ASME 1974; 96: 477–489.

Heshmat

Walton

. Oil-free turbocharger demonstration paves way to gas turbine engine applications. In: ASME Turbo Expo 2000, Munich, Germany, 8–11 May 2000.

Zhiming

Yan-yang

Youbai

. Theory of hydrodynamic lubrication of journal bearing. Beijing, China: Higher Education Press, 1986, pp. 20–24 (in Chinese).

Yie

Yanzong

Zheng

. Rotor dynamics. Beijing, China: Tsinghua University Press, 1987, pp. 63–67 (in Chinese).

10.

Pinkus

Sterlicht

. Theory of hydrodynamic lubrication. New York: McGraw-Hill, 1961.