Effects of couple stresses on pure squeeze EHL motion of circular contacts

H. M. Chu, Wang-Long Li, S. Y. Hu

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

A method for investigating the pure squeeze action in an isothermal elastohydrodynamically lubrication (EHL) problem, i.e., circular contacts lubricated with couple stress fluid, was developed. A constant load condition was used in the calculations. The initial conditions such as pressure profiles, normal squeeze velocities, and film shapes were obtained from the classical hydrodynamic lubrication theory at a specified large central film thickness. The coupled transient modified Reynolds, elasticity deformation, and load equilibrium equations are solved simultaneously. The simulation results reveal that the effect of the couple stress is equivalent to enhancing the lubricant viscosity, thus enlarging the film thickness. The effect of couple stress in thin film lubrication varies with film size. That is, the thinner the lubricating film is, the more obvious the effect of couple stress is. For larger characteristic length, materials parameter, and load, the central pressure, central film thickness, and rigid separation are larger than those of smaller characteristic length under the same load. The time needed to achieve maximum central pressure and the Hertzian pressure increases with increasing characteristic length.

Original languageEnglish
Pages (from-to)77-84
Number of pages8
JournalJournal of Mechanics
Volume22
Issue number1
DOIs
Publication statusPublished - 2006 Jan 1

Fingerprint

Couple Stress
Lubrication
lubrication
Contact
Film thickness
film thickness
Motion
Loads (forces)
equilibrium equations
lubricants
Contacts (fluid mechanics)
Lubrication Theory
Lubricants
Elasticity
Hydrodynamics
elastic properties
hydrodynamics
Viscosity
viscosity
Thin films

All Science Journal Classification (ASJC) codes

  • Condensed Matter Physics
  • Mechanical Engineering
  • Applied Mathematics

Cite this

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Effects of couple stresses on pure squeeze EHL motion of circular contacts. / Chu, H. M.; Li, Wang-Long; Hu, S. Y.

In: Journal of Mechanics, Vol. 22, No. 1, 01.01.2006, p. 77-84.

Research output: Contribution to journalArticle

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