The pressure-viscosity coefficient for Newtonian EHL film thickness with general piezoviscous response

Scott Bair*, Yuchuan Liu, Q. Jane Wang

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

104 Scopus citations

Abstract

There has been a long-standing need for a piezoviscous parameter αfilm that, together with the ambient viscosity μ0, will completely quantify the Newtonian rheology so that the film thickness for liquids that do not shear-thin in the inlet may be calculated as h =h(μ0, αfilm,...), regardless of the details of the pressure-viscosity response. It seems that Blok's reciprocal asymptotic isoviscous pressure has certain advantages over the conventional pressure-viscosity coefficient, which is poorly suited for this purpose. The first detailed review of piezoviscous models for low pressures is provided. A simulation code that is apparently stable for all realistic pressure-viscosity response was utilized with diverse piezoviscous models and model liquids to develop a satisfactory definition of αfilm that reads αfilm=[1-exp(-3)]/[∫03/α * μ(0)dp/μ(p)]; 1/α*= ∫0μ(0)dp/μ(p). In the case of μ=μ0 exp(αp), αfilm = α and formulas are provided for other models.

Original languageEnglish (US)
Pages (from-to)624-631
Number of pages8
JournalJournal of Tribology
Volume128
Issue number3
DOIs
StatePublished - Jul 1 2006

Keywords

  • Elastohydrodynamics
  • Film thickness
  • Newtonian
  • Piezoviscous
  • Pressure-viscosity coefficient

ASJC Scopus subject areas

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

Fingerprint

Dive into the research topics of 'The pressure-viscosity coefficient for Newtonian EHL film thickness with general piezoviscous response'. Together they form a unique fingerprint.

Cite this