Detail publikace

Utváření mazacích filmů u nenewtonovských maziv

LIU, Y. WANG, G.J. KŘUPKA, I. HARTL, M. BAIR, S.

Český název

Utváření mazacích filmů u nenewtonovských maziv

Anglický název

The Shear-Thinning Elastohydrodynamic Film Thickness of a Two-Component Mixture

Typ

článek v časopise - ostatní, Jost

Jazyk

en

Originální abstrakt

Lubricant base oils are often blends of different molecular weight cuts to arrive at a specified ambient pressure viscosity and, to improve the temperature-viscosity behavior or to simply increase the viscosity, viscosity-modifying polymer additives are often added to the base oil. This paper investigates the effect of mixture rheology on EHL film thickness using EHL contact measurements and a full numerical analysis for three synthetic lubricants including two single-component lubricants PAO650, and PAO100 and a mixture of these. The pressure and shear dependences of the viscosity of these lubricants were measured with high-pressure viscometers; viscosities were not adjusted to fit experiment. The point contact film thicknesses for these lubricants in pure rolling were measured using a thin-film colorimetric interferometry apparatus. Numerical simulations based on the measured rheology show very good agreement with the measurements of film thickness while the Newtonian prediction is up to twice the measurement. These results validate the use of realistic shear-thinning and pressure-viscosity models which originate from viscosity measurements. It is conceivable that simulation may provide a means to "engineer" lubricants with the optimum balance of film-thickness and friction though intelligent mixing of components.

Český abstrakt

Článek shrnuje výsledky teoretického řešení a experimentálního studia problematiky utváření mazacích filmů při užití nenewtonovských maziv.

Anglický abstrakt

Lubricant base oils are often blends of different molecular weight cuts to arrive at a specified ambient pressure viscosity and, to improve the temperature-viscosity behavior or to simply increase the viscosity, viscosity-modifying polymer additives are often added to the base oil. This paper investigates the effect of mixture rheology on EHL film thickness using EHL contact measurements and a full numerical analysis for three synthetic lubricants including two single-component lubricants PAO650, and PAO100 and a mixture of these. The pressure and shear dependences of the viscosity of these lubricants were measured with high-pressure viscometers; viscosities were not adjusted to fit experiment. The point contact film thicknesses for these lubricants in pure rolling were measured using a thin-film colorimetric interferometry apparatus. Numerical simulations based on the measured rheology show very good agreement with the measurements of film thickness while the Newtonian prediction is up to twice the measurement. These results validate the use of realistic shear-thinning and pressure-viscosity models which originate from viscosity measurements. It is conceivable that simulation may provide a means to "engineer" lubricants with the optimum balance of film-thickness and friction though intelligent mixing of components.

Klíčová slova česky

EHL; reologie; tloušťka mazacího filmu

Klíčová slova anglicky

EHL; elastohydrodynamics; rheology; film thickness; shear-thinning; non-Newtonian; viscosity

Rok RIV

2008

Vydáno

17.04.2008

Nakladatel

ASME

Místo

USA

ISSN

0742-4787

Časopis

ASME Transaction, Journal of Tribology

Ročník

130

Číslo

2

Strany od–do

021502-1–021502-7

Počet stran

7

BIBTEX


@article{BUT44742,
  author="Ivan {Křupka} and Martin {Hartl},
  title="The Shear-Thinning Elastohydrodynamic Film Thickness of a Two-Component Mixture",
  journal="ASME Transaction, Journal of Tribology",
  year="2008",
  volume="130",
  number="2",
  month="April",
  pages="021502-1--021502-7",
  publisher="ASME ",
  address="USA",
  issn="0742-4787"
}