On the sensitivity of the asperity pressures and temperatures to the fluid pressure distribution in mixed-film lubrication

Liming Chang, Yongwu Zhao

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

This paper studies the sensitivities of the asperity pressures and temperatures to the fluid pressure distribution in concentrated contacts operating in the regime of mixed-film lubrication. Two fluid pressure distributions are used in the study. One is a Hertz-like distribution that neglects micro-EHL responses of the lubricant, and the other models the micro-EHL effects with significant pressure rippling. The asperity pressures and temperatures are deterministically calculated in time by numerically solving the asperity-contact and the transient energy equations as the two surfaces move relative to each other. The contact is simulated for sufficient time duration until the samples of the calculated asperity variables reach a statistical equilibrium that reflects the random-process nature of the problem. Parametric analyses are carried out that cover a wide range of operating conditions of practical interest. The results obtained consistently suggest that the asperity pressures and temperatures are not sensitively related to the fluid pressure. This insensitivity supports the use of any fluid pressure distribution consistent with the underlying mixed-film problem, rather than determining it by numerically solving the Reynolds equation at every time step of the simulation process. The study lays a foundation on which to advance modeling of the mixed-film contacts with a proper balance among model robustness, computational efficiency and solution accuracy.

Original languageEnglish (US)
Pages (from-to)77-85
Number of pages9
JournalJournal of Tribology
Volume122
Issue number1
DOIs
StatePublished - Jan 1 2000

Fingerprint

fluid pressure
lubrication
pressure distribution
Pressure distribution
Lubrication
Fluids
sensitivity
Reynolds equation
Temperature
temperature
random processes
lubricants
Computational efficiency
Random processes
Contacts (fluid mechanics)
Lubricants
simulation
energy

All Science Journal Classification (ASJC) codes

  • Mechanics of Materials
  • Mechanical Engineering
  • Surfaces and Interfaces
  • Surfaces, Coatings and Films

Cite this

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On the sensitivity of the asperity pressures and temperatures to the fluid pressure distribution in mixed-film lubrication. / Chang, Liming; Zhao, Yongwu.

In: Journal of Tribology, Vol. 122, No. 1, 01.01.2000, p. 77-85.

Research output: Contribution to journalArticle

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