Water-lubricated journal bearing

PV-value, side-leakage flow, power loss and frictional temperature rise of a water-lubricated journal bearing operating at near-full eccentricity, assuming adiabatic conditions.

✓ gevalideerd tegen origineelorigineel: /calculators/waterlub.htm
Water-lubricated journal bearing — original diagram from /calculators/waterlub.htm
Lagerlengtegetal, L/D1.21
PV-waarde0.4 MPa·m/s
Debietgetal, C_q0.725
Vermogensverlies, N = μF·2πn/601707.14 W
Zijlekkage, Q109.722
Wrijvingsopwarming, ΔT13.4 K

The legacy source also has a Viscosity, η field, but never uses it in the PV-value, side-leakage, power-loss or heating formulas — confirmed against the original waterlub.js, which reads it from the form and never references it again. It has zero effect on any result, so it is not exposed as an input here.

Methode & referenties

  • Water-lubricated bearings operate at near-full eccentricity (ε=0.999 assumed) because of water’s low viscosity.
  • Frictional heating assumes adiabatic boundary conditions: power loss N is drained by the natural side leakage Q (plus any forced flow) when submerged.
  • Flow through the bearing can be improved with axial grooves (forced flow via an applied pressure difference) — see the hydraulic diameter calculator.

De berekening is een letterlijke overzetting van de originele client-side JavaScript van /calculators/waterlub.htm. Resultaten zijn geverifieerd gelijk aan het origineel via een geautomatiseerde golden-master-test. Geen enkele formule is opnieuw afgeleid of “verbeterd”.

Water-lubricated journal bearing — Engineering ABC