Journal Bearing - Minimum Film Thickness

Minimum oil-film thickness in a journal bearing - Sommerfeld-based approximation for safe operation.

BearingFilm thicknessHydrodynamic

Journal radiusmmRadial clearancemmEccentricity ratio ε

Min film thickness: 45.0µm

Status: Safe full-film

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Formula, assumptions, and limits

h_{min} = c (1 - \varepsilon)

Symbol	Meaning	Unit
$c$	Radial clearance	mm
$ε$	Eccentricity ratio

Source: Hamrock - Fundamentals of Fluid Film Lubrication

In short

Minimum oil-film thickness in a journal bearing - Sommerfeld-based approximation for safe operation.

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