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  1. Home
  2. Impact Of Oil-water Emulsions On Lubrication Performance Of Ship Stern Bearings.
  1. Home
  2. Impact Of Oil-water Emulsions On Lubrication Performance Of Ship Stern Bearings.

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Impact of oil-water emulsions on lubrication performance of ship stern bearings.

Zhenjiang Zhou1,2,3, Xincong Zhou1,2, Qipeng Huang4,5

  • 1State Key Laboratory of Maritime Technology and Safety, Wuhan University of Technology, Wuhan, 430063, China.

Scientific Reports
|December 29, 2024

View abstract on PubMed

Summary
This summary is machine-generated.

Water contamination in ship stern bearing lubricants creates emulsions affecting performance. High water content can increase viscosity and bearing lift but also friction, while low water content offers benefits under specific conditions.

Keywords:
Lubrication performanceOil-water mixtureStern bearingsThermal-hydrodynamic modelViscosity

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Area of Science:

  • Tribology
  • Lubrication Science
  • Maritime Engineering

Background:

  • Extreme maritime events cause water ingress into ship stern bearing lubricants, forming oil-water emulsions.
  • Existing research primarily addresses low water content, leaving high water content impacts under-explored.

Purpose of the Study:

  • To investigate the lubrication performance of ship stern bearings under varying oil-water emulsion concentrations.
  • To develop a model accounting for emulsification viscosity and rough surface contact.

Main Methods:

  • Viscosity measurements of oil-water mixtures to derive an emulsification viscosity equation.
  • Development of a thermal elastohydrodynamic lubrication model for stern bearings.
  • Numerical simulations to analyze lubrication behavior in different flow regimes.

Main Results:

  • Identified two distinct flow regimes: water-in-oil (W/O) and oil-in-water (O/W).
  • In W/O regime, increased viscosity, higher oil film thickness, and journal lift observed, alongside increased friction and power consumption.
  • O/W regime showed lower friction and temperature rise under high-speed, light-load conditions, but detrimental effects under low-speed, heavy-load conditions.

Conclusions:

  • Water content critically influences stern bearing lubrication performance through emulsification.
  • Findings provide insights for enhancing bearing design and operational reliability in maritime applications.