Publication detail

Analytical Formula for the Ratio of Central to Minimum Film Thickness in a Circular EHL Contact

ŠPERKA, P. KŘUPKA, I. HARTL, M.

English title

Analytical Formula for the Ratio of Central to Minimum Film Thickness in a Circular EHL Contact

Type

journal article in Web of Science

Language

en

Original abstract

Prediction of minimum film thickness is often used in practice for calculation of film parameter to design machine operation in full film regime. It was reported several times that majority of prediction formulas cannot match experimental data in terms of minimum film thickness. These standard prediction formulas give almost constant ratio between central and minimum film thickness while numerical calculations show ratio which spans from 1 to more than 3 depending on M and L parameters. In this paper, an analytical formula of this ratio is presented for lubricants with various pressure–viscosity coefficients. The analytical formula is compared with optical interferometry measurements and differences are discussed. It allows better prediction, compared to standard formulas, of minimum film thickness for wide range of M and L parameters.

English abstract

Prediction of minimum film thickness is often used in practice for calculation of film parameter to design machine operation in full film regime. It was reported several times that majority of prediction formulas cannot match experimental data in terms of minimum film thickness. These standard prediction formulas give almost constant ratio between central and minimum film thickness while numerical calculations show ratio which spans from 1 to more than 3 depending on M and L parameters. In this paper, an analytical formula of this ratio is presented for lubricants with various pressure–viscosity coefficients. The analytical formula is compared with optical interferometry measurements and differences are discussed. It allows better prediction, compared to standard formulas, of minimum film thickness for wide range of M and L parameters.

Keywords in English

point contact lubrication; minimum film thickness; prediction formula

Released

07.09.2018

Publisher

MDPI

ISSN

2075-4442

Volume

6

Number

3

Pages from–to

1–11

Pages count

11

BIBTEX


@article{BUT150792,
  author="Petr {Svoboda} and Petr {Šperka} and Ivan {Křupka} and Martin {Hartl},
  title="Analytical Formula for the Ratio of Central to Minimum Film Thickness in a Circular EHL Contact",
  year="2018",
  volume="6",
  number="3",
  month="September",
  pages="1--11",
  publisher="MDPI",
  issn="2075-4442"
}